Webasto DBW 2010 Instrucciones de operación
- Tipo
- Instrucciones de operación
– While a Webasto heater is in use, the product surface, connected hoses, ducting
and air outlet(s) may become hot to the touch. Contact with skin may cause burns.
– Improper installation or repair of Webasto heating systems can cause fire or the
leakage of deadly carbon monoxide leading to serious injury or death.
– NEVER attempt to install or repair a Webasto heating system unless you have
successfully completed Webasto factory training and have the technical skills,
technical information, tools and equipment required to properly complete the
necessary procedures. Only genuine Webasto parts may be used.
– Webasto rejects any liability for problems and damage caused by the system being
installed by untrained personnel.
– Webasto products produce temperatures high enough to ignite surrounding
combustible materials such as inflammable liquids, gases, vapor, and other
combustible matter. The heater must be switched off when loading or unloading
inflammable materials to prevent the risk of explosion.
– ALWAYS and carefully follow Webasto installation and repair instructions and heed
all WARNINGS.
Scholastic Series Heater™
Coolant Heating System for
Diesel Powered School Buses
Installation / Operation Guide
Table of Contents
www.webasto.us 3 Webasto Thermo & Comfort N.A., Inc.
Contents Page
1. Safety and General Information 5
1.1 Scope and Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Safety Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Additional Documentation to be Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.4 General Safety Regulations and Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.4.1 General Safety Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5 Regulation for Installation in the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.1 Position of the Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.2 Fuel Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.3 Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.4 Combustion Air Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.5 Water Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5.6 Hot Water Outlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.6 Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2. Purpose / Version 8
2.1 Purpose of the Coolant Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.1 Scholastic Heater Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3. Installation - Overview 9
3.1 Installation site / Installation position. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Model plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 CE mark . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Installation 10
4.1 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 Installation Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.3 Mounting the Scholastic Heater™ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.4 Exhaust Pipe Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.5 Combustion Air Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.6 Connection to the Heating System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.6.1 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.6.2 Various Plumbing Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.6.3 Plumbing Instructions (Typical Installations) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.7 Fuel Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.7.1 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.7.2 Fuel Standpipe Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.7.3 Fuel Filter Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.7.4 Fuel Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.8 Electrical Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.8.1 Power / Control Harness Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.8.2 Connecting the Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5. Circuit Diagrams 24
6. Initial Start-up and Operation 27
6.1 Initial Start-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
6.2 Operating the Scholastic Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.2.1 Switching ON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.2.2 Switching Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.3 Engine Preheating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.4 Boost Heating for Engine and Passenger Compartment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table of Contents
Webasto Thermo & Comfort N.A., Inc. 4 www.techwebasto.com
6.5 Operation with 7-Day Digital Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
7. Troubleshooting 34
7.1 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
7.2 Quick Check Troubleshooting Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
7.3 Heater Test Unit (Webasto P/N 5011070). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
7.4 Heater Lock Out Reset Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
8. Heater Maintenance 38
8.1 Annual Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
9. Technical Data 39
9.1 Scholastic Heater Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
9.1.1 Scholastic Heater™ Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
9.2 Coolant Circulating Pump Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
9.2.1 Coolant Circulating Pump Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
9.3 Mounting Tray Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
10.Technical Service Bulletins / Product Information 43
www.webasto.us 5 Webasto Thermo & Comfort N.A., Inc.
Safety and General Information
1. Safety and General Information
1.1 Scope and Purpose
This installation guide is intended to support authorized
Webasto trained distributors, dealers and personnel in
the installation of the Scholastic Heater™ coolant
heating system.
Webasto Thermo & Comfort North America, Inc. does
not recommend the installation and servicing of Webasto
products by untrained, unauthorized personnel or end-
users.
Installations and servicing of Webasto products by
untrained, unauthorized personnel and end-users will
release Webasto Thermo & Comfort North America, Inc.
and Webasto authorized distributors, dealers and
personnel from responsibility for damage to Webasto
product or collateral property and personal injury.
Any use, operation, installation, modification or
application of the product not described in Webasto
manuals, or subjecting the product to extreme or unusual
conditions beyond the limits of specified performance
characteristics is misuse of the product.
Failure to comply with all installation instructions is a
misuse of Webasto product. The same applies for repairs
without using genuine Webasto service parts.
This will void the coolant heaters “Official Marks of
Conformity.”
1.2 Safety Signals
The purpose of safety symbols is to attract your attention
to possible hazardous conditions. This guide uses a series
of symbols and signal words which are intended to
convey the level of importance of the safety messages.
The progression of symbols is described below.
Remember that safety messages by themselves do not
eliminate danger and are not a substitute for proper
accident prevention measures.
DANGER: Indicates that non-compliance
with instructions or procedures WILL result
in serious injury or death.
WARNING: Indicates that non-compliance
with instructions or procedures MAY result
in serious injury or death.
CAUTION: Indicates that non-compliance
with instructions or procedures COULD
result in damage to the vehicle or
equipment.
NOTE: Provides information we feel you would
like to have. It could have to do with
procedures and tips that will help you work
more efficiently.
1.3 Additional Documentation to be Used
This guide contains all of the information and procedures
necessary for the installation of the Scholastic Heater™.
The use of additional documentation is normally not
necessary. Vehicle specific installation guides (when
available) may be used as complementary information if
necessary.
1.4 General Safety Regulations and
Information
The general safety regulations for the prevention of
accidents and relevant operating safety instructions must
be observed at all times.
1.4.1 General Safety Notes
The heater may only be installed in vehicles, with a
minimum coolant capacity of 2.6 US Gal. (10 litres).
The heater must not be installed in the passenger
compartments of the vehicle. Should the heater be
installed in such a compartment, the installation box
must be sealed tight against the vehicle interior. There
must be sufficient ventilation of the installation box from
the exterior in order not to exceed a maximum
temperature of 140 °F (60 °C) in the installation box.
Excessive temperatures may cause malfunctions.
DANGER: Due to the danger of poisoning
and suffocation, the heater must not be
operated in enclosed areas, such as garages
or workshops, without an exhaust venting
system, not even if the start-up is activated
by the timer or remote start device.
Webasto Thermo & Comfort N.A., Inc. 6 www.techwebasto.com
Safety and General Information
1.5 Regulation for Installation in the
Vehicle
Read this installation guide in its entirety before
installing this equipment.
1.5.1 Position of the Heater
• Parts of the vehicle body and other components
in the immediate vicinity of the heater must be
protected against excessive heat and the danger
of contamination by fuel or oil.
• The internal combustion heater must not pose a
fire hazard even when overheated. This
requirement is deemed to have been met if care
is taken during installation to ensure an
adequate distance from all parts, as well as
adequate ventilation and if fire-resistant
materials or heat shields are used.
• For passenger carrying vehicles such as shuttle
busses, transit busses, and coaches, the heater
must not be installed in the passenger cabin.
• The model/ Serial plate or a duplicate thereof
(duplicate model/ Serial plate) must be fitted in
such a way that it is still clearly legible when the
heater has been installed in the vehicle.
• When positioning the heater, all reasonable
precautions must be taken to minimize the risk
of personal injury or damage to items in the
vehicle.
• A clearly visible indicator within the user's field
of vision must show when the heater is switched
on or off.
1.5.2 Fuel Supply
The coolant heater may only be operated with the
specified fuel (Diesel 1, Diesel 2, Arctic grade, Kerosene
and certain military spec. fuels).
For the routing of fuel lines, the following important
regulations must be adhered to:
• Fuel lines are to be installed in such a way that
they remain unaffected by torsional stresses
created by vehicle and engine movement. They
must be protected against mechanical damage.
• Fuel lines must be securely fastened to the
vehicle every 12 inches (30 cm.) or more often
along the total length from heater to fuel tank.
• Fuel-carrying parts are to be protected against
excessive heat and are to be installed so that any
dripping or evaporating fuel can neither
accumulate nor be ignited by hot components or
electrical equipment.
• In buses, fuel lines are not to be located in the
passenger area or in the driver’s compartment.
Fuel supply must not be by means of gravity or
pressurization of the fuel tank.
• The fuel tank must either be equipped with a
vent cap or be ventilated in another way
(ventilation line).
• The fuel filler neck must not be located in the
passenger compartment and must have a tightly
fitting cap to prevent any fuel leaks.
• The type of fuel and the fuel filler neck must be
clearly identified on heaters for liquid fuel, for
which the fuel supply is separate from the fuel
supply for the vehicle.
• A sign must be affixed to the fuel filler neck
warning that the heater must be switched off
before refuelling. An identical warning must also
be included in the manufacturer's operating
instructions.
1.5.3 Exhaust System
• The exhaust outlet must be positioned in such a
way that exhaust fumes cannot get into the
interior of the vehicle through ventilation
devices, hot-air inlets or open windows.
1.5.4 Combustion Air Inlet
• The air for the combustion chamber of the
heater must not be extracted from the
passenger cabin of the vehicle.
• The air inlet must be positioned in such a way
that it cannot be obstructed by other objects.
1.5.5 Water Inlet
• The supply of water to be heated must be
protected against freezing with a suitable
antifreeze additive to the required strength as
directed by the manufacturer.
• The supply of water to be heated must be
uncontaminated by corrosive compounds and
other impurities.
• The inlet line must be protected from damage.
1.5.6 Hot Water Outlet
• Hot water lines within the vehicle must be
positioned or protected in such a way as to
exclude all risk of injury or damage caused by
direct contact.
• The water outlet line must be protected so that
it cannot be obstructed by other objects or the
flow of water through the lines be blocked.
www.webasto.us 7 Webasto Thermo & Comfort N.A., Inc.
Safety and General Information
NOTE: Failure to follow the installation
instructions and the notes contained therein will
lead to all liability being refused by Webasto.
The same applies if repairs are carried out
incorrectly or with the use of parts other than
genuine Webasto service parts. This will result
in the invalidation of the type approval for the
heater and therefore of its homologation / type
licence.
1.6 Contact Information
Webasto Thermo & Comfort N.A., Inc. is pleased to
provide this installation manual for use with this new
heater. When installed in accordance with the guidelines
stated in this manual, you can expect to provide years of
trouble-free, enjoyable operation for your customer.
This manual represents our latest effort to produce the
best technical documentation possible.
In our efforts towards continuous, ongoing product
improvement, we encourage our customers to write to
us with their comments or criticisms concerning this
manual or product.
Please write to us at:
Webasto Thermo & Comfort N.A., Inc.
Technical Documentation Group
15083 North Road
Fenton MI 48430
You are also invited to fill out our online questionnaire
concerning our technical documentation and web site at:
www.techwebasto.com
If you have any immediate questions concerning this
guide, the installation procedures within or the product
itself, please call us at:
(800) 860-7866 or send a fax to: (810) 593-6001
Webasto Thermo & Comfort N.A., Inc. 8 www.techwebasto.com
Purpose / Version
2. Purpose / Version
Figure 1: Webasto Scholastic Heater™ cutaway view
2.1 Purpose of the Coolant Heater
Coolant heaters are used in connection with the vehicle’s
own heating system
– to heat the vehicle interior,
– to defrost vehicle windows and
– to preheat water-cooled engines
The water heater operates independently of the engine
and is connected to the cooling system, the fuel system
and the electrical system of the vehicle.
2.2 Versions
2.2.1 Scholastic Heater Version
Water heater for "diesel" fuel.
The Scholastic Heater™ water heater is designed for use
on 12 Volt electrical systems.
1
2
3456 7 8 9 10 11 12 13 14
15 16 17
18
19
20212223242526
1 Control unit
2 Motor
3 Electronic ignition coil
4 Coupler
5 Combustion air fan
6 Reduction gearing
7 Fuel solenoid valve
8 Preheat thermostat
9 Nozzle preheat cartridge
10 Electrode clamp
11 Ignition electrodes
12 Bleed screw
13 Outlet water pipe (1 in. OD.)
14 Fuel nozzle
15 Overheat fuse
16 Control thermostat
17 Overheat limiter
18 Inlet water pipe (1 in. OD.)
19 Heat exchanger
20 Combustion tube
21 Combustion air swirler
22 Exhaust pipe
23 Flame detection photocell
24 Fuel pump (single line, no return)
25 Fuel connection pipe (JIC #4)
26 Combustion air intake bellows
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Installation - Overview
3. Installation - Overview
NOTE: The water heater must be installed
outside the passenger cabin.
3.1 Installation site / Installation position
The heater must be installed in as low a position as
possible to allow the heater and circulating pump to be
bled automatically. This is particularly important as the
circulating pump is not self-priming.
The installation must be performed in accordance with
the installation instructions provided in this guide.
NOTE: If the vehicle manufacturer has issued
specific installation instructions, they must be
followed.
3.2 Model plate
The model plate must be positioned so that it cannot be
damaged and must be clearly legible when the heater is
installed (otherwise a duplicate model plate must be
used).
Inapplicable years must be erased from the model plate.
3.3 CE mark
The Scholastic Heater™ (DBW 2010 variant) water heater
carries the CE mark since it complies with the regulations
in force. The heater satisfies the requirements of class A.
As a result, the following supplement applies:
NOTE: This is a class A device. This device may
induce radio interference in residential areas; in
this case, the owner may be required to
undertake appropriate measures.
As a rule, installation inside of an auxiliary compartment
of the school bus represents sufficient screening. Please
contact the Webasto hotline in the event that radio
interference occurs nevertheless.
Webasto Thermo & Comfort N.A., Inc. 10 www.techwebasto.com
Installation
4. Installation
Webasto will take you step by step through the
installation process to ensure successful operation for
years to come. The installation must be performed in
accordance with the installation instructions provided in
this manual.
4.1 General Information
DANGER: Due to the risk of carbon
monoxide poisoning and asphyxiation, the
heater must never be installed inside the
passenger compartment.
The heater is to be installed in an existing enclosure
(spare battery compartment) on the driver’s (road) side of
vehicle. The installation template provided with the
heater kit must be used.
Do not mount to the slide-out tray. The heater and tray
must be mounted solidly. The heater inertia safety switch
will only function properly if the heater and tray are
mounted solidly.
The heater should be installed as low as possible in the
cooling system to assure static bleeding of the heater and
the circulating pump.
CAUTION: The coolant circulating pump is
not self-priming. Always prime coolant
circulating pump, heater and cooling circuit
before initial starting of heater. See
Section 6. "Initial Start-up and Operation".
4.2 Installation Locations
NOTE: This manual does not cover all possible
installations. This manual is a general guideline
only. For special applications or installations
differing from what is described in this manual,
contact Webasto Thermo & Comfort N.A., Inc.
directly at 1-800-432-8371 for further
information.
Figure 2: Installation locations
HERE
HERE
www.webasto.us 11 Webasto Thermo & Comfort N.A., Inc.
Installation
4.3 Mounting the Scholastic Heater™
Tray Kit mounting in existing enclosure on vehicle,
e.g. spare battery box.
1. Ensure that the enclosure is large enough to
accommodate the heater. Use the installation
template provided with the heater kit.
2. The installation enclosure must provide adequate
ventilation for combustion air requirements [4 in² (20
cm²)].
3. Lay the supplied installation template in the
enclosure. Center punch the exhaust, fuel, electrical
and 4 mounting hole locations.
4. Drill all required holes to the dimensions as shown on
the template.
5. Solidly bolt the tray with heater mounted inside the
enclosure.
Before drilling into a frame, consult the
manufacturer concerning any possible
restrictions!
Do not drill holes through top or bottom of
vehicle frame flanges!
Do not weld vehicle frame or flanges!
Figure 3: Tray mount template (Included with heater kit).
MOUNTING TEMPLATE FOR TRAY MOUNT
SCHOLASTIC HEATER
NOTE:
HEATER TRAY MUST BE SOLIDLY MOUNTED.
DO NOT MOUNT ON SLIDE-OUT TRAY.
HEATER INERTIA SWITCH WILL ONLY FUNCTION
PROPERLY IF UNIT IS MOUNTED SOLIDLY.
ALLOW 2” CLEARENCE
FOR SERVICE
EXHAUST
3/8” X 1” SLOTS
(4) PLACES
3ӯ
2ӯ
3/4ӯ
FOLD 90°
1-7/16”
12”
23 - 3/4”
WEBASTO ITEM NO. 907 905
FUEL
ELECTRIC
Webasto Thermo & Comfort N.A., Inc. 12 www.techwebasto.com
Installation
4.4 Exhaust Pipe Connection
WARNING: Due to the risk of carbon
monoxide poisoning and asphyxiation,
exhaust system components must be
routed in a manner that prevents exhaust
fumes from entering the passenger
compartment.
1. Insert the supplied flexible exhaust pipe onto the
heater exhaust outlet and fasten with the exhaust
clamp. Secure the outlet end to the chassis with a
P-clip.
2. The exhaust system must discharge on the street
(driver) side of vehicle. The discharge opening of the
exhaust pipe must not point in the direction of
travel, and so located that any clogging caused by
snow or mud is not to be expected. See Figure 5.
CAUTION: Route the exhaust components
in a way that prevents them from touching
vehicle parts that may be damaged by heat
(brake lines, electrical wiring, hoses, etc.).
Do not direct exhaust outlet towards heat
sensitive vehicle components.
The exhaust pipe I.D. 1 1/2” (38 mm) can have a length
up to 16’ (5 m) and may have several bends totaling no
more than 270° overall.
Rigid exhaust pipe may be used; bends must be formed
with the smallest bending radius allowable being 3 3/8”
(85 mm). Do not weld pipe to make 90° corners.
Figure 4: Incorrect Vs. Correct pipe bend forming
Figure 5: Exhaust outlet position
4.5 Combustion Air Supply
Under no circumstances may the combustion air be
taken from areas occupied by people. The combustion
air intake opening must not point in the direction of
travel. It must be located such that it cannot become
clogged with dirt or snow and cannot suck in splashing
water.
A ventilation opening for combustion air requirements
measuring at least 20 cm² (4 inch²) is required if the
heater is installed in an enclosed box. The size of the
ventilation opening must be increased accordingly if the
temperature in the box exceeds the permitted ambient
temperature of the heater. See Technical data.
10°
10°
The exhaust pipe must be securely attached
no further than 150 mm (6 in.) from the end
of the exhaust pipe to ensure that the angle
of 90° ± 10° verticle-down is maintained.
Discharge direction almost vertical 90° ± 10°
www.webasto.us 13 Webasto Thermo & Comfort N.A., Inc.
Installation
4.6 Connection to the Heating System
4.6.1 General Information
An efficient heating system must have an adequate
supply of hot water to all heater cores. The amount of
hot water available to a typical three or four heater-core
system depends on the water pumps capability and the
amount of restriction within the coolant system.
The Webasto heater is equipped with a high-
performance circulating pump designed specifically for
bus heating applications, and when plumbed in
accordance with the following instructions, will maximize
the heating systems efficiency.
The coolant-circulating pump, bottom of enclosure or
tray, must be mounted at least 6” (15 cm) below the
lowest permissible coolant level of the vehicles cooling
system. A minimum of 10% of a good quality antifreeze
should be maintained in the cooling system at all times.
Heater and water pump fit 1” (25.4 mm) ID. heater hose
meeting SAE 20 R3 specifications. Silicone hose requires
special hose clamps.
NOTE: Heater hose must meet SAE 20 R3
specifications. Silicone heater hose requires
special hose clamps. Hose clamps must be
tightened to 4 Nm (35 lb-in.) torque.
The heater is connected to the vehicle heating system as
shown in Figures 8 or 9, depending on the type of
heating system the vehicle is equipped with. The system
must contain at least 10 litres (2.6 US Gal.) of coolant.
The system must be filled with an antifreeze and water
mixture as recommended by the vehicle manufacturer.
Coolant flow throughout the system must be maintained
in all operating conditions.
If desired, shut-off valves can be installed at the engine
inlet and outlet connections of the coolant heater circuit,
although, shut-off valves are not mandatory. All valves
should remain open throughout the year.
Figure 6: Typical school bus heating circuit
NOTE: To maintain optimum heater condition,
run heater for 20 minutes monthly during the
off-season. Ensure any shut-off valves are open
before operating the coolant heater.
• Use good quality, heavy duty 1” ID. coolant hose for
the coolant heater circuit.
• Hoses must be installed without kinks and bends
which may restrict coolant flow.
• To ensure proper bleeding of air, keep hoses rising if
possible. Avoid “goose necks” to prevent trapping air.
• Hoses must be supported where required to prevent
chaffing and damage from vehicle components.
• Hose connections must be secured by hose clamps to
prevent them from slipping off.
Webasto Thermo & Comfort N.A., Inc. 14 www.techwebasto.com
Installation
• Coolant heater flow direction should match the flow
direction of the engine’s coolant circulation system.
NOTE: The hose clamps must be tightened
with a torque of 4 Nm (35 lb-in.).
The use of silicone hose requires special hose
clamps.
If possible, for good performance and engine preheating,
separate the heater supply and return connections at the
engine as far apart as is practical. See Figure 7.
Figure 7: Ensure optimum cross-flow
CAUTION: The cooling system must be bled
carefully before using the heater for the
first time or after replacing the coolant.
Proper venting of trapped air can be identified by the
circulating pump operating almost silently. Poor bleeding
may cause the self-resetting temperature limiter to trip or
the overheat fuse to open whilst the heater is operating.
An open overheat fuse (white wires) must be replaced
with a new fuse P/N 406287A.
4.6.2 Various Plumbing Configurations
Select the appropriate plumbing configuration according
to the customers requirements and the vehicle system
type.
Figure 8 illustrates a series heating system.
This system works in this fashion:
Heated water (coolant) from the engine travels through
the first heater core in the circuit, then on to the next
heater core in circuit, and on to the next, etc. Each core
adds some restriction, resulting in decreased water flow.
Not only is water flow reduced, but also water
temperature is reduced by each successive heater core
resulting in the last core receiving water that is usually
too cool to be effective.
Figure 9 illustrates a parallel heating system.
This system works in this fashion:
Heated water (coolant) from the engine travels through a
common supply and return circuit, but unlike a series
system, the heater cores are connected across the circuit
at intervals along its length. Each core shares the
available coolant and heat equally, resulting in increased
heating efficiency and decreased coolant restriction.
Unfortunately, water flow and volume may not be
sufficient to satisfy heating requirements efficiently in a
parallel system.
A fuel fired Webasto heater with a high capacity coolant
pump can significantly increase the available heat
supplied to both series and parallel systems and has the
added ability to ensure sufficient coolant volume and
flow through the system, increasing interior heating
efficiency
Optimum Cross-Flow Through Engine
www.webasto.us 15 Webasto Thermo & Comfort N.A., Inc.
Installation
Figure 8: Heating circuit with exchangers arranged in series.
Figure 9: Heating circuit with exchangers arranged in parallel.
SCHOLASTIC
HEATER
1
2
3
4
5
76
9
10
8
1. Coolant supply connection
2. Original coolant hose path
3. Scholastic Heater™
4. Coolant circulating pump
5. Forward / step heat exchangers
6. Mid heat exchanger(s)
7. Rear heat exchanger(s)
8. Coolant return hose
9. Coolant return connection
10. Engine coolant pump
1
2
3
4
5
76
9
10
SCHOLASTIC
HEATER
88
8
8
1. Coolant supply connection
2. Original coolant hose path
3. Scholastic Heater™
4. Coolant circulating pump
5. Forward / step heat exchangers
6. Mid heat exchanger(s)
7. Rear heat exchanger(s)
8. Coolant return hose
9. Coolant return connection
10. Engine coolant pump
Webasto Thermo & Comfort N.A., Inc. 16 www.techwebasto.com
Installation
4.6.3 Plumbing Instructions (Typical
Installations)
CAREFULLY READ AND UNDERSTAND THE
FOLLOWING INSTRUCTIONS BEFORE PROCEEDING
WITH INSTALLATION!
1. Remove the radiator cap and release system
pressure.
2. Close the shut off valves for heating system, if so
equipped, or pinch off the supply and return line
with hose clamping pliers.
3. Plumb into the system as shown in figure A, B or C.
Two long brass 90° elbows with mounting flanges
have been provided for making connections into
existing coolant lines. To install:
– remove heater hose access cover(s) running
down left side of floor inside bus at a location
over top of heater installation.
– find and identify heating circuit supply hose.
This is the hose you will use to plumb the
Webasto heater into the system.
– locate and mark suitable location on floor, above
heater, where brass elbows will be installed.
NOTE: When properly installed, the elbows
should protrude down into the heater enclosure
area where they can be easily connected to the
coolant pump inlet and heater outlet.
– once you are satisfied with the location, making
certain there are no obstructions, you can now
bore 2 holes (1-1/4”) through the floor.
– from inside the bus, drop elbows down through
the floor and align with the heating circuit
supply hose, inlet elbow pointing forward and
outlet elbow rearward.
– secure elbow flanges to floor with sheet metal
screws.
4. From inside the heater enclosure, connect the inlet
elbow (supply) to the coolant pump and the outlet
elbow to the Webasto heater outlet with rubber
elbows and fittings provided.
5. From inside the bus, cut the previously identified
heating supply hose at a point where it can be
connected to the inlet and outlet elbows.
6. Connect the heater supply line running from the
engine to the inlet elbow. Connect the other cut
end of the supply line to the outlet elbow.
7. Secure all hose connections with hose clamps.
8. Remove hose clamping pliers and/ or open shut off
valves.
9. Purge air from the Webasto heater by opening the
bleeder valve. Refer to figure 1, item 12, on page 8,
for identification.
CAUTION: The cooling system must be bled
carefully before using the heater for the
first time or after replacing the coolant.
Proper venting of trapped air can be identified by the
circulating pump operating almost silently. Poor bleeding
may cause the self-resetting temperature limiter to
respond or the overheat fuse to open whilst the heater is
operating. An open overheat fuse (white wires) must be
replaced with a new fuse P/N 406287A.
10. Top off engine coolant as per engine manufacturer’s
recommendations and re-install the radiator cap.
Do not install the previously removed heater hose access
covers at this time. Hose connections will require
inspection and re-tightening of clamps once installation
is completed and tested. Refer to section 6 “Initial
Operation”.
NOTE: Heater hose must meet SAE 20 R3
specifications. Silicone heater hose requires
special hose clamps. Hose clamps must be
tightened to 4 Nm (35 lb-in.) torque.
www.webasto.us 17 Webasto Thermo & Comfort N.A., Inc.
Installation
4.7 Fuel Supply
4.7.1 General Information
The fuel is drawn from the vehicles fuel tank through a
fuel standpipe. This standpipe can be utilized on vehicles
with a threaded port in the fuel tank, or if no threaded
port is available, a 1” (25 mm) hole can be drilled into
the tank and the universal tank-boss installed as shown
in figure 10.
NOTE: Check local and State code and
regulations for exceptions before drilling into
the fuel tank!
4.7.2 Fuel Standpipe Installation
CAUTION: Keep the fuel standpipe 2” from
bottom of the fuel tank.
This separate fuel pickup precludes any effect of
pressure.
Figure 10: Webasto fuel standpipe
A
B
C
DE
G
H
I
J
F
K
M
N
L
B
A. Fuel standpipe tube
B. Compression fitting - 1/4” NPT
C. Bushing - 1/4” to 3/8” NPT
D. Check valve - 1/4” NPT
E. Hose barb - 1/4” NPT x 1/4” barb
F. Fuel tank with threaded port
G. Nut
H. Metal washer
I. Neoprene gasket
J. Tank boss
K. Fuel tank with 25 mm (1.0 in.) hole
L. Distance from tank floor - 50 mm (2.0 in.)
M. Fuel tank floor
N. Close up view
Webasto Thermo & Comfort N.A., Inc. 18 www.techwebasto.com
Installation
Installing the standpipe using tank boss assembly:
1. Bore a 25mm (1”) hole through top of fuel tank. See
item K, Figure 10.
2. Remove sharp burrs and smooth edges with emery
cloth.
3. Determine length of standpipe when installed. End
should sit at least 50 mm (1.0 in) above tank bottom.
Cut off excess standpipe at a 45 degree angle.
Remove burrs.
4. Loosely assemble item G, item H, item I, and item J
as shown in Figure 11. Refer to Figure 10 for item
identification.
5. Place sealing compound on threads of item B and
thread into item J. Tighten item B completely.
6. Slide standpipe into hole at angle. Slip one shoulder
of item J, inside the hole as shown in Figure 11.
Figure 11: Standpipe installation - illustration 1
7. Bring standpipe up to horizontal and insert opposite
shoulder under the tank hole. See Figure 12.
Figure 12: Standpipe installation - illustration 2
Detail View
www.webasto.us 19 Webasto Thermo & Comfort N.A., Inc.
Installation
8. Center standpipe in tank hole. See Figure 13.
Figure 13: Standpipe installation - illustration 3
9. Pull up on standpipe and tighten in place with the
clamping nut. See item G in Figure 14. Do not over-
tighten causing rubber washer to squeeze out!
Figure 14: Standpipe installation - illustration 4
4.7.3 Fuel Filter Installation
The Scholastic Heater™ is equipped with a spin-on fuel
filter. Fuel filters require changing at least annually and
in cases of dirty fuel more often.
The fuel filter assembly should be mounted securely
between the vehicle frame rails close to the fuel tank.
After installation, before the heater is fired for the first
time, the fuel filter MUST be filled with CLEAN diesel
fuel. When replacing the fuel filter, this procedure must
be repeated to ensure proper firing and operation.
NOTE: Check local and State codes and
regulations for fuel filter mounting locations.
NOTE: To prevent fuel nozzle failure, always
use CLEAN fuel from a known CLEAN source for
priming fuel systems and filters.
NOTE: The Webasto Scholastic Heater™ is
equipped with an internal self-priming fuel
pump.
Figure 15: Fuel filter assembly
G
Fuel
Tank
Webasto Thermo & Comfort N.A., Inc. 20 www.techwebasto.com
Installation
4.7.4 Fuel Line
Route and secure fuel line from fuel tank, to fuel filter,
and to heater. Do not route fuel line over frame rails!
Always route through or under the frame rail. Use
grommets to protect fuel line whenever routed through
holes.
Connect fuel line to fuel standpipe using 1/4” (6 mm)
fuel hose meeting SAE 30RI specifications.
CAUTION: On School Bus applications, fuel
lines must not cross over top of the vehicle
frame rails. Check local and State codes
and regulations for exceptions.
Fuel lines must be secured every 12 inches or less and
kept clear of hot exhaust components and moving parts
(driveshaft, wheels, etc.).
NOTE: Use supplied hose clamps to secure fuel
line connections.
Figure 16: Fuel line parameters
Fuel Line
Fuel Filter
Standpipe
Scholastic
Heater
Fuel Tank
A
B
A = Maximum suction length 10 m (33 ft)
B = Maximum suction height 2.0 m (6.5 ft)
www.webasto.us 21 Webasto Thermo & Comfort N.A., Inc.
Installation
4.8 Electrical Connections
Ideally, the heater power supply should be directly from
the vehicle’s batteries or main buss-bar.
The heater control unit is equipped with low voltage
protection. It is imperative that the vehicle batteries be
kept in good condition for optimal heater operation.
IMPORTANT: All power connections must be fused
within 14” of the battery.
4.8.1 Power / Control Harness Connections
A. Route item 1 into the vehicle cab in the area where
the switch or timer is to be installed.
B. Route item 4 to vehicle battery box and connect to
batteries as shown in Figure 17. Brown wire to
ground, red wire with fuse holder to positive.
Ensure battery connections are clean and protected
with an anti-corrosive compound.
C. Item 3 (main connector) should be left unconnected
until all electrical components are installed and
heater is ready for the initial start-up.
A weather sealed fuse holder, item 5, is fitted to the
main power input to protect the heater and wiring
harness.
Figure 17: Power and control harness assembly
1
2
3
4
5
6
+
+
+
+
–
–
–
–
1. Switch / Timer Harness
2. Heater Harness (Pre-installed in
enclosure or tray)
3. Main Harness Connector
4. Power Supply Harness
5. Main Fuse
6. Main Vehicle Batteries
Webasto Thermo & Comfort N.A., Inc. 22 www.techwebasto.com
Installation
4.8.2 Connecting the Controls
The heater can be switched on and off using the
following Webasto controls:
• Toggle Switch, see Figure 18, on page 22 and Figure
21, on page 24.
• Timer Model 1529, see Figures 19, on page 23 and
Figure 22, on page 25.
• Timer Model 1531, see circuit diagrams in Figures 20,
on page 23 and Figure 23, on page 26.
• NOI (White) Timer, see circuit diagram on pages 37-38.
Figure 18: Toggle switch
CAUTION: All the cables and wires that are
not required must be insulated against
accidental shorting or grounding.
Heater Control Harness Connection
Using a 12 or 24 Volt Switch
1. White (Ground)
2. Red (Power)
3. Black (On signal)
4. Green (Operation indication)
56
12
78
34
CONNECTOR X3
(MATING END SHOWN)
X3
X5
X4
1
5
3
6
2
Connector X5 (Violet)
For School Bus operation,
connect to ignition source.
Heater Control Harness Connection
Using 1529 Comfort Timer
1. Red (Power)
2. Red (Power)
3. Green (Operation indication)
4. Optional (Dash lights)
5. White (Ground)
6. Black (On signal)
www.webasto.us 23 Webasto Thermo & Comfort N.A., Inc.
Installation
Figure 19: 7-Day, 3 Program Timer model 1529
Figure 20: 7-Day, 3 Program Comfort Timer model 1531
56
12
78
34
CONNECTOR X3
(MATING END SHOWN)
X3
X5
X4
1
5
3
6
Connector X5 (Violet)
For School Bus operation,
connect to ignition source.
Heater Control Harness Connection
Using 1531 Comfort Timer
1. Red (Power)
2. Not Used
3. Green (Operation indication)
4. Optional (Dash lights)
5. White (Ground)
6. Black (On signal)
Webasto Thermo & Comfort N.A., Inc. 24 www.techwebasto.com
Circuit Diagrams
5. Circuit Diagrams
Figure 21: Scholastic Heater™ with On/Off switch - connection diagram
BROWN
BROWN
BROWN
REDRED
RED
BT
E
F
G
A
B
C
J
S1
DS
F5
X1
H
D
WHITE
GREEN
RED
BLACK
BT BATTERY
DS INDICATOR LIGHT
E IGNITION ELECTRODES
F1 FUSE 15A
F2 FUSE 20A
F3 FUSE 15A
F4 OVERHEAT FUSE 138°C
F5 FUSE 30A
HR HEATING ELEMENT
(fuel pre-heater)
I INERTIA SAFETY SWITCH
K1 RELAY (on / off switch)
K2 RELAY (fuel pre-heater)
L1 SOLENOID VALVE
L2 IGNITION COIL
M1 COOLANT CIRCULATION PUMP
M2 HEATER MOTOR
R FLAME DETECTOR
S1 ON / OFF SWITCH (heater)
S2 PREHEAT (FUEL) THERMOSTAT
(blue and blue wires)
S3 CONTROL THERMOSTAT
(green and red wires)
S4 TEMPERATURE LIMITER
(green and green wires)
X1 9-PIN HARNESS CONNECTOR (round)
X2 3-WAY CONNECTOR
WHITE
WHITE
WHITE
VIOLET
F4
t°
t° t°
WHITE
WHITE
WHITE
BLACK
BLUE
VIOLET
GREEN
GREEN
GREEN
RED
ORANGE
WHITE
BROWN
BLACKBLACK
BLUE
GREEN
YELLOW
BROWN
BROWN
BROWN
BLUE
BLUE
BLACK
BLACK
GREEN
RED
BLUE
BLACK
ORANGE
GREEN
BROWN
BROWN
BROWN
BROWN BROWN
BROWN
BROWN
BROWN
RED
RED
BROWN
L1
R
L2
E
S4S3
M2
HR
S2
K2
M1
A
B
C
C
A
B
M
1
2
4
1
3
6
5
2
52 17
4
68
65
3
4
2
1
85
86
87
30
+
–
A2 - CONTROL UNIT
A1 - HEATER
1 2
3
45
62
1
1 2
3
4
5
6
7
8
BLACK
BROWN
M
BLUE
BLACK
GREEN
I
2
1
3
K1
85
86
87
30
X2
F1
F2
F3
E
FCDAB
RED
BLUE
ORANGE
GREEN
RED
RED
GRAY
(Remote pump activation)
GRAY
GRAY
www.webasto.us 25 Webasto Thermo & Comfort N.A., Inc.
Circuit Diagrams
Figure 22: Scholastic Heater™ with 7-day digital timer model 1529 - connection diagram
BT BATTERY
E IGNITION ELECTRODES
F1 FUSE 15A
F2 FUSE 20A
F3 FUSE 15A
F4 OVERHEAT FUSE 138°C
F5 FUSE 30A
HR HEATING ELEMENT
(fuel pre-heater)
I INERTIA SAFETY SWITCH
K1 RELAY (heater activation)
K2 RELAY (fuel pre-heater)
L1 SOLENOID VALVE
L2 IGNITION COIL
M1 COOLANT CIRCULATION PUMP
M2 HEATER MOTOR
P1 7-DAY TIMER MODEL 1529
R FLAME DETECTOR
S2 PREHEAT (FUEL) THERMOSTAT
(blue and blue wires)
S3 CONTROL THERMOSTAT
(green and red wires)
S4 TEMPERATURE LIMITER
(green and green wires)
X1 HARNESS CONNECTOR (round)
X2 3-WAY CONNECTOR
X3 TIMER HARNESS CONNECTOR
X4 TIMER CONNECTOR
X5 FUNCTION CONNECTOR
WHITE
WHITE
WHITE
VIOLET
F4
t°
t° t°
WHITE
WHITE
H
WHITE
WHITE
BLACK
BLUE
VIOLET
GREEN
GREEN
GREEN
RED
ORANGE
WHITE
BROWN
BLACKBLACK
BLUE
GREEN
YELLOW
BROWN
BROWN
BROWN
BLUE
BLUE
BLACK
BLACK
GREEN
RED
BLUE
BLACK
ORANGE
GREENGREEN
BROWN
BROWN
BROWN
BROWNBROWN
BROWN
BROWN BROWN
BROWN
BROWN
BROWN
REDREDRED
RED
RED
RED
BROWN
L1
R
L2
E
S4S3
M2
HR
S2
K2
BT
M1
A
B
C
C
A
B
M
1
2
4
1
3
6
5
2
52 17
4
68
65
3
4
2
1
85
86
87
30
+
–
A2 - CONTROL UNIT
A1 - HEATER
1 2
3
45
62
1
1 2
3
4
5
6
7
8
BLACK
BROWN
M
E
F
G
A
B
C
J
BLUE
BLACKBLACK
GREEN
I
2
1
3
TO
TIMER
K1
85
86
87
30
F5
X1
X2
F1
F2
F3
E
F CDAB
RED
BLUE
ORANGE
GREEN
RED
RED
GRAY
(Remote pump activation)
D
GRAY
GRAY
WHITE
GREEN
RED
BLACK
P1
2
3
5
1
6
4
2
3
4
5
6
7
8
BLUE/YELLOW
VIOLET
GRAY
BROWN
RED
BLACK
YELLOW
VEHICLE
IGNITION +
DASH LAMPS
(OPTIONAL)
WIRING CABLE
TO THE HEATER
VIOLET
7-DAY TIMER 1529
RED
X5
X3
X4
Webasto Thermo & Comfort N.A., Inc. 26 www.techwebasto.com
Circuit Diagrams
Figure 23: Scholastic Heater™ with 7-day digital timer model 1531 - connection diagram
BT BATTERY
E IGNITION ELECTRODES
F1 FUSE 15A
F2 FUSE 20A
F3 FUSE 15A
F4 OVERHEAT FUSE 138°C
F5 FUSE 30A
HR HEATING ELEMENT
(fuel pre-heater)
I INERTIA SAFETY SWITCH
K1 RELAY (heater activation)
K2 RELAY (fuel pre-heater)
L1 SOLENOID VALVE
L2 IGNITION COIL
M1 COOLANT CIRCULATION PUMP
M2 HEATER MOTOR
P2 7-DAY TIMER MODEL 1531
R FLAME DETECTOR
S2 PREHEAT (FUEL) THERMOSTAT
(blue and blue wires)
S3 CONTROL THERMOSTAT
(green and red wires)
S4 TEMPERATURE LIMITER
(green and green wires)
X1 HARNESS CONNECTOR (round)
X2 3-WAY CONNECTOR
X3 TIMER HARNESS CONNECTOR
X4 TIMER CONNECTOR
X5 FUNCTION CONNECTOR
P2
2
3
5
1
6
4
8
10
4
11
12
2
1
VIOLET
GRAY
BROWN
BROWN
RED
BLACK
WHITE
GREEN
RED
BLACK
YELLOW
7-DAY TIMER 1531
X4
X3
VEHICLE
IGNITION +
DASH LAMPS
(OPTIONAL)
WIRING CABLE
TO THE HEATER
X5
WHITE
WHITE
WHITE
VIOLET
F4
t°
t° t°
WHITE
WHITE
H
WHITE
BLACK
BLUE
VIOLET
GREEN
GREEN
GREEN
RED
ORANGE
WHITE
BROWN
BLACKBLACK
BLUE
GREEN
YELLOW
BROWN
BROWN
BROWN
BLUE
BLUE
BLACK
BLACK
GREEN
RED
BLUE
BLACK
ORANGE
GREEN
BROWN
BROWN
BROWN
BROWNBROWN
BROWN
BROWN BROWN
BROWN
BROWN
BROWN
REDREDRED
RED RED
BROWN
L1
R
L2
E
S4S3
M2
HR
S2
K2
BT
M1
A
B
C
C
A
B
M
1
2
4
1
3
6
5
2
52 17
4
68
65
3
4
2
1
85
86
87
30
+
–
A2 - CONTROL UNIT
A1 - HEATER
1 2
3
45
62
1
1 2
3
4
5
6
7
8
BLACK
BROWN
M
E
F
G
A
B
C
J
BLUE
BLACK
GREEN
I
2
1
3
K1
85
86
87
30
F5
X1
X2
F1
F2
F3
E
F CDAB
RED
BLUE
ORANGE
GREEN
RED
RED
GRAY
(Remote pump activation)
D
GRAY
GRAY
WHITE
GREEN
RED
BLACK
TO
TIMER
www.webasto.us 27 Webasto Thermo & Comfort N.A., Inc.
Initial Start-up and Operation
6. Initial Start-up and Operation
6.1 Initial Start-up
NOTE: Refer to the safety instructions in the
operating and maintenance instructions.
The operating and maintenance instructions
must be read through without fail before
starting the heater.
If the heater suffers a fault during operation, the fault
must be located and remedied.
1. Check your installation for:
– loose nuts and bolts.
– exhaust pipe routing and clamp tightness.
– loose hose clamps.
– routing and securing of wiring and heater hoses.
– kinked or pinched hoses.
– battery connection and polarity.
– disconnect control thermostat on Webasto heat
exchanger (red and green wire, see Figure 1,
item 16, on page 8 for reference).
2. Top off or refill cooling system with coolant as per
engine manufacturer’s recommendations.
3. Connect power/ switch extension harness to
waterproof plug.
4. Open shut-off valves and driver’s heater valve.
5. Set heater controls to maximum heat position and
turn off Air Conditioning if applicable.
6. Switch “On” Webasto heater and check:
– green indicator light on.
– circulating pump in operation.
7. Start the vehicle engine and run it at a fast idle for 10
minutes to purge air from the Webasto coolant
heater and all of the heat exchangers. While the
engine is running check:
– hose connections for leaks.
– coolant level in the expansion tank and add
coolant as needed.
– use bleeder valve on top of Webasto heat
exchanger to purge out trapped air. See Figure
1, item 12, on page 8 for reference.
8. Shut off the engine.
9. Plug in control thermostat, the blower motor starts
and the fuel pump primes the fuel lines. After 10 to
25 sec. the fuel solenoid opens and the electronic
ignition coil ignites the air fuel mixture.
NOTE: Installations with long fuel lines may
require a second start attempt to prime the fuel
system. Cycle switch or timer off and on to
reset control unit. Coolant temperature must
be below 155 °F (68 °C) at heater before heater
will begin heating operation.
10. Allow heater to run until coolant is hot and heater
cycles off. During this period, monitor system for
any coolant or fuel leaks.
NOTE: The engine temperature gauge may
read a lower temperature depending on the
location of the temperature sensor on the
engine.
11. Temperature differential between water inlet and
outlet should not exceed 10 °C (18 °F) during
heating operation.
12. Switch “Off” Webasto heater.
13. Re-tighten hose clamps to 4 Nm (35 lb-in.) and
inspect installation for leaks.
14. Install any panels and access covers removed during
installation.
15. Complete the warranty card and send to Webasto
Thermosystems.
16. Install the enclosure cover if equipped. Installation is
now complete.
NOTE: Necessary information to complete the
warranty card can be found on the name plate
on top of the heater burner head. The
completion of the warranty card will ensure full
warranty coverage. Please mail completed
warranty card within 30 days of purchase to
register your heater.
Webasto Thermo & Comfort N.A., Inc. 28 www.techwebasto.com
Initial Start-up and Operation
6.2 Operating the Scholastic Heater
WARNING: Due to the risk of carbon monoxide poisoning and asphyxiation, the heater must
never be operated in closed spaces such as garages and workshops without adequate exhaust
extraction.
WARNING: Due to the risk of explosion, the heater must be switched off while refueling and at
fueling stations.
WARNING: Due to the risk of explosion, the heater must never be operated in areas where
explosive materials, fumes or dusts may be present.
WARNING: Webasto heaters must
be switched “off” when re-fueling at filling stations and/or
while loading or unloading flammable materials for transport, to prevent the risk of explosion.
Please review owner’s manual for safety and use instructions.
Before starting the heater for the first time, complete this checklist.
HEATER MOUNTING Complete
(Yes/No/Comments)
1 Is the heater installation safely secure / rigid?
(Ensure that all bracket bolts are tight)
2
Is there a safe clearance from heat generating
Components? (I.e. exhaust, etc...)
3 Is there sufficient clearance between heater and any
vehicle moving components under all operating
conditions? (steering cranked to extreme positions,
torqued engine, suspension, etc...)
4 Is the heater mounted in an acceptable position
according to the limitations noted in the
installation manual?
5 Is the heater installed in a protected location from
road debris and splash-water or items stored in the same area?
6 Is there a sufficient amount clearance
between the heater and the ground? (Coolant heaters only)
www.webasto.us 29 Webasto Thermo & Comfort N.A., Inc.
Initial Start-up and Operation
COOLANT SYSTEM Complete (Yes/No/
Comments)
1 Is there a safe clearance (min 4 in.) from heat generating components?
(exhaust, etc...)
2 Is there a safe clearance from sharp edges / objects?
Ensure a heat protective has been installed (if applicable)
3 Are there any kinks, sharp bends or the possibility for pinched hoses or
harnesses, cuts and rub through?
4 Have all the hose clamps been properly positioned and tightened?
5
Has the coolant system been topped off and bleed per the vehicle
manufacture’s specifications for proper mixture and type?
6 Has a pressure test been performed on the coolant system under all
operating conditions?
7 Have the coolant hoses been installed so that they are below the coolant
filler cap?
8 Has the coolant flow direction been verified?
ELECTRICAL Complete
(Yes/No/Comments)
1
Has all wiring been safely secured away from moving components
and / or heat sources?
2
Check for proper power and ground connections.
3
Has blower motor functionality been tested (if applicable)?
4
Check for proper fuse tap connection.
5
Verify the correct fuses are in the specified locations per the
installation manual.
6
Ensure heater and vehicle fuse boxes are closed and secure. Was the
Webasto fuse block installed in a location protected from water and /
or moisture?
7
Ensure blower motor resistor (1.0?) is securely mounted and has
sufficient clearance from any plastic component and battery.
8
Ensure battery is mounted securely and connections are properly
tightened.
9
Ensure battery is at ? 12.2Vdc for 12V, 24.4Vdc for 24V.
Webasto Thermo & Comfort N.A., Inc. 30 www.techwebasto.com
Initial Start-up and Operation
FUEL SYSTEM Complete (Yes/No/
Comments)
1
Is the standpipe properly mounted in the fuel tank?
(sealed, structural integrity maintained).
2
Validate the standpipe does not interfere with function of sending
unit by checking fuel gauge for proper operation before completing
installation of tank.
3
Verify that all fuel lines are properly secured and are a safe distance
(min. 4 in.) from exhaust systems and / or moving components.
4
Check all fuel lines for leaks or kinks.
5
Check fuel line clamps for proper positioning and tightness. Ensure
fuel system is free of leaks.
6
Ensure fuel pump is securely mounted in a cool location
NOTE: Vehicle fuel tank area is generally a location with minimal
sound transfer path to vehicle interior.
EXHAUST SYSTEMS Complete
(Yes/No/Comments)
1
Is the muffler and clamps securely tightened?
2
Has muffler and exhaust tube been routed a safe distance (min. 2 in.)
from flammable material?
3
Ensure drain-holes are drilled in low bend areas of exhaust tube.
4
Ensure exhaust is venting a safe distance from any vehicle interior
openings.
5
Ensure exhaust is venting in the direction that will not cause back
pressure while driving.
COMBUSTION AIR INTAKE Complete
(Yes/No/Comments)
1
Is the combustion air intake drawing fresh air from a non-turbulent
location? (i.e. not in direction of travel)
2
Ensure air intake system is securely fastened.
www.webasto.us 31 Webasto Thermo & Comfort N.A., Inc.
Initial Start-up and Operation
If you have any questions, contact our technical support team at (800) 860-7866 or via email at:
.
HEATER FUNCTION Complete (Yes/No/
Comments)
1
Ensure heater starts and runs for a minimum of 20 minutes.
2
Ensure vehicle blower turns “ON”.
3
Ensure warm air is blown out of interior vents after blower is
activated.
4
Ensure timer (control device) is functioning.
5 Check and Modify CO2 setting as needed based on altitude (will the
heater “live” or spend a lot of time above XXXXXX Feet)
(See service manual for instructions to make adjustment)
COSMETICS Complete (Yes/No/
Comments)
1
Has the vehicle interior, engine compartment, trunk & glove
compartment been inspected for cleanliness after installation.
2
Has user manual placed in glove box?
3
Is the vehicle clock time correct after disconnecting the battery?
Webasto Thermo & Comfort N.A., Inc. 32 www.techwebasto.com
Initial Start-up and Operation
6.2.1 Switching ON
Before switching the Webasto heater on, set vehicle-
heating system to the “Heat” position and open any shut
off valves. Depending on the type of control installed in
the instrument panel of the vehicle, the heater can be
operated by the following methods.
Using a Switch:
When the switch is used for switching “ON” the heater,
the “Operation Indicator” integrated in the switch is
illuminated and the heater begins operation.
Using a Timer:
Upon pressing the “Instant Heat” button on the timer
face, the “Operation Indicator” on the timer lights up
and the heater begins operation.
Heater Start-up Sequence:
The heater motor and coolant circulating pump begin
operation. After approximately 10 to 25 seconds the fuel
solenoid valve opens and fuel is sprayed into the
combustion chamber. At the same time, the electronic
ignition coil produces a high voltage (8000 V) spark at
the tip of the ignition electrodes and the mixture of fuel
and air in the combustion chamber is ignited. As soon as
combustion is detected by the photo resistor (flame
detector), the electronic ignition coil is de-energized and
combustion continues on its own (ignition process is only
required to ignite the flame). At this point the heater is
working and producing heat.
The Scholastic heater will cycle ON and OFF until:
1. The Scholastic heater is switched OFF.
2. Set run-time has elapsed on the timer.
3. The vehicle battery voltage drops below 10.5V.
4. The Webasto heater runs out of fuel.
5. A fault lock out occurs, indicated by the operating
indicator light being off during the cool down cycle
(as would happen during an overheat situation).
NOTE: If the heater is switched on while the
engine is at operating temperatures above 155
°F (68 °C) only the operation indicator and the
coolant circulation pump will be activated. The
engine coolant temperature must fall below
155 °F (68 °C) at the heater before the heater
will begin heating operation.
NOTE: Switching the Webasto heater on
during the cool-down or “after-run” period is
allowed. The heater will revert to normal
operational mode.
6.2.2 Switching Off
When heating is no longer required, switch the Webasto
heater off. The fuel solenoid valve halts the fuel supply,
combustion stops and the indicator light turns off. The
Combustion air fan and the water pump remain on for
another 2-3 minutes (after run cycle) purging the
combustion chamber of any fumes.
6.3 Engine Preheating
Set the timer 30 min. to 1 hr. before you want to start
the engine. The heater will start up at the set time. (See
timer operating instructions). Or switch the toggle
switch or “Instant On” switch on your timer in the
vehicle dash to “ON”. The heater will start up.
When the run time has elapsed on your timer or engine
preheating is no longer required, switch the Webasto
heater “OFF”. The heater will begin a brief after-run
(cool down) cycle.
6.4 Boost Heating for Engine and
Passenger Compartment
Switch the toggle switch (or the “Instant On” button of
the timer) in the vehicle dash to “On”. The heater will
start up if the coolant temperature is below 167 °F (75
°C). Above this temperature only the water pump will
run.
When boost heating is no longer required, switch the
Webasto heater “Off”. The heater will begin a brief
after-run (cool-down) cycle.
6.5 Operation with 7-Day Digital Timer
The digital timer with 3 time settings permits the heater
to be switched on and off instantly, or automatically at 3
programmable starting times.
The operating time of the heater can be pre-selected. It
is possible to program 3 different heating programs
according to your individual needs.
Only one preset starting time can be activated at any one
time. When the ignition is switched on, the current time
of the day and the day of the week are displayed.
When the heater is in operation, the display and the
buttons of the timer are illuminated.
Programmed Heater Operation
Three memory locations numbered 1 to 3 are available.
Each memory location can be assigned a given time
together with the day of the week.
www.webasto.us 33 Webasto Thermo & Comfort N.A., Inc.
Initial Start-up and Operation
Pre-selected Starting Times
The pre-selected starting time is the time at which the
heater will be switched on automatically.
We recommend that memory locations 1 and 2 be used
for presetting starting times within 24 hours of setting
the timer.
Memory location 3 can be used for a starting time within
the next 7 days of setting the timer.
NOTE: Memory location 3 can be reserved for
a starting time within the next 7 days of setting
the timer. Location 3 is useful for occasional
weekend or field trip operations outside of the
normal schedule. By repeatedly pressing the
program button, starting time program 1, 2 or 3
can be viewed and preset.
Operating Time
The period of time during which the heater is in
operation is referred to as operating time. The heater
remains in operation for as long as the operating time
has been preset.
Heater operation can be pre-selected for any time from
as little as 1 minute to a maximum of 120 minutes
(factory preset is 60 minutes).
Remaining Operating Time
The remaining operating time refers to the period of time
the heater still continues to remain in operation. It can
only be changed while heater is in operation.
NOTE: If the ignition is switched off while the
heater is in operation, the remaining operating
time of 5 minutes flashes on the timer display
and the heater continues to operate for this
period of time. See “Remaining Operating
Time” to adjust this time setting.
Setting the Digital Timer
Refer to the operating card or manual supplied with your
timer. Instructions are also available for reading and
downloading from our technical web site.
Go to:
http://www.techwebasto.com/thermosystems_bus.htm
Webasto Thermo & Comfort N.A., Inc. 34 www.techwebasto.com
Troubleshooting
7. Troubleshooting
7.1 General Information
CAUTION: Troubleshooting requires
profound knowledge about structure and
theory of operation of the heater.
Troubleshooting may only be performed by
Webasto trained and certified, skilled
personnel.
This section describes troubleshooting procedures for the
Scholastic Series coolant heater. Troubleshooting is
normally limited to the isolation of defective
components.
Before troubleshooting, check for and eliminate the
following causes for problems:
– fuel supply (plugged fuel filter or pinched fuel
line)
– corrosion of battery terminals
– corrosion of electrical wiring, connections and
fuses
– loose contacts or wrong crimping on connectors
– shut-down initiated by temperature limiter
(automatic reset)
– shut-down initiated by overheat fuse (replace
fuse)
– shut-down initiated by inertia switch (manual
reset)
NOTE: After the correction of a problem or
defect, a functional test of the heater as
installed in the vehicle must be performed.
Table 1. Quick Check Troubleshooting Matrix
7.2 Quick Check Troubleshooting Matrix
PROBLEM
Switch On No Function
Control Light OFF after 30 Seconds
Blower Motor in Unit Inoperative
Blower Motor in Unit No Prime Cycle
Blower Motor in Unit No After-run
Coolant Circulating Pump Inoperative
Ignition Spark Absent
Combustion Does Not Take Place
Combustion Stops After 30 Seconds
Combustion Cannot Be Stopped
During Combustion Light Color Smoke
During Combustion Dark Color Smoke
Heating Unit Overheating
Electrical Fuse
Electrical Harness
and Connections
Inertia Switch
ON / OFF Switch or Wiring
Over
hea
t Fuse (White Wires)
Temperature Limiter (Green Wires)
Control Thermostat (Green and Red Wires)
Flame Detector (Photo-cell)
Control Unit
Ignition Electrodes
Ignition Coil – Coil Wires
Electric
Motor
Fuel Supply
Fuel Pump
Fuel Solenoid Valve
High Pressure
N
ozzle
C
o
o
lant Circulating Pump
Combustion A
ir Intake
Exhaust System
Heating System
Voltage Supply
CHECK, REPAIR OR REPLACE AS NECESSARY
www.webasto.us 35 Webasto Thermo & Comfort N.A., Inc.
Troubleshooting
7.3 Heater Test Unit (Webasto P/N 5011070)
Figure 24: Test unit P/N 5011070A
The tester unit has been designed to quickly check the
proper operation of the various heater components. By
using the tester in place of the heater control unit, you
are able to manually control the heater to test
components and actually operate the unit in heating
mode.
The actual testing is completed in two steps, first you
perform an individual component test and then a manual
start and run test, both designed to pinpoint actual
problems in the heater system.
CAUTION: Do not attempt to test fire or
run heater with burner head open. Ensure
burner head is properly closed and secured
in place.
NOTE: Make sure the Water Pump and Motor
Switches (1) & (2) are in the OFF position before
connecting to the heater.
SETUP:
A. Remove connector blocks from heater control unit,
inspect for loose wires, corrosion and proper wire
connections.
B. Plug control unit connector blocks into tester.
C. Set heater switch/timer to “ON” and turn vehicle
heater valve to “FULL” mode (if equipped).
D. Proceed to component test procedures.
Webasto Thermo & Comfort N.A., Inc. 36 www.techwebasto.com
Troubleshooting
COMPONENT TEST PROCEDURE and RESULTS
* Inertia Switch:
All Scholastic heaters are equipped with a manual reset inertia switch located on the tray floor near the coolant pump.
The switch has a round red diaphragm and about the size of a 25 cent piece on top.
The purpose of this switch is to stop heater operation in the event the vehicle is involved in an accident or receives a
strong impact shock, e.g. hitting a curb. When the switch responds, the fan motor circuit is interrupted thus stopping
air and fuel delivery.
Always check to make certain the inertia switch has not been tripped. Resetting is accomplished by depressing the red
diaphragm on top of the switch. You should hear an audible click whenever the switch is reset.
MANUAL TEST RUN of HEATER:
A. Turn the WATER PUMP switch (4) ON
B. Turn the MOTOR switch (5) ON
C. Push and hold the FUEL SOLENOID VALVE button (7)
ON (starts fuel flow to combustion chamber)
D. Push and hold the IGNITION SPARK COIL button (6)
ON (starts electrodes sparking) until combustion has
taken place.
NOTE: Hold IGNITION SPARK COIL button (5) ON until FLAME DETECTOR LED (3) lights or combustion is
heard, then release; in any case do not hold button on for more than 15 seconds or damage to the coil may
result.
TEST RESULTS:
1. LED (3) lights and combustion achieved
– operation normal
2. Combustion achieved but no LED (3) light
– check flame detector
Test Step Result If not
Tester connected BATTERY LED (1) unit lights up
CONTROL THERMOSTAT LED (2)
lights up
- test input voltage at control
terminals B4(+) and B2(-)
- check battery connections
- check battery voltage
- test switch/ timer
- test control thermostat on heater Normal operating range
- approx. 75 °C (167 °F) or higher
open (no heat required)
- approx. 68 °C (155 °F) or lower
closed (heat required)
Push FUEL SOLENOID VALVE button (7) several
times
clicking of solenoid should be
heard
- test temperature fuse (if equipped)
- test overheat limiter
- test solenoid valve
Push IGNITION SPARK COIL
button (6)
sparking should be heard - check electrode gap
- test ignition spark coil
Turn MOTOR switch (5) “ON“ motor should run - reset *inertia switch
- test motor
Turn WATER PUMP switch (4) “ON“ pump should run - test pump
Table 2. Test procedures and result
www.webasto.us 37 Webasto Thermo & Comfort N.A., Inc.
Troubleshooting
3. Combustion not achieved and no LED (3) light
– check fuel nozzle
– check fuel pressure
– check for blocked fuel lines (dirt or ice)
– check ignition electrodes for damage and set gap
E. Heater should now be in heating mode and will continue to run until you release the fuel solenoid valve button
(7) which stops fuel flow and extinguishes the flame immediately. Allow the heater to continue running for
approximately 30 seconds (cool down) after which, turn the WATER PUMP switch (4) and the MOTOR switch (5) OFF.
NOTE: If flame does not stop when the FUEL SOLENOID VALVE button (7) is released, turn MOTOR switch (5)
OFF to stop heater. Check and repair fuel solenoid valve accordingly.
F. Once the manual test run has been successfully completed, set the heater switch or timer to OFF, remove the
tester and reconnect the control unit. Once done, set the switch or timer to ON. If the heater or a heater component
does not respond, the control unit is defective. Replace the control unit and retest the heater.
NOTE: Since the heater operates in the 68 °C (155 °F) to 75 °C (167 °F) On to Off / Off to On range, and the
vehicle engine may be hot [e.g. coolant above 75 °C (167 °F)], the heater will not start until the coolant
temperature is below 68 °C (155 °F). THIS IS NORMAL and does not indicate a problem.
7.4 Heater Lock Out Reset Procedure
The control unit continuously monitors the heater operation. The control unit identifies errors on individual heater
components and faults during operation. Should the control unit experience component errors and operational faults,
the heater may be shut down.
Causes:
The heater is shut down (fault lock-out) if:
– No or incorrect start
– Temperature sensor defective
– Overheating sensor interrupt or short circuit
– Overheating sensor installed incorrectly
– Ceramic glow pin interrupt or short circuit
– Fan motor overload or blocked or short circuit or interrupt
– Error in the fuel metering pump or circuit
– Under voltage or over voltage for longer than 20 seconds.
– Control unit defective
– Overheating
Effects:
The fuel supply is stopped if the heater overheats.
The heater continues to run in the same way as if it is switched off manually.
After the heater stops the control unit may set in fault lock-out mode.
Heater Lock out Reset Procedure
:
1. Using switch or standard timer control, turn heater on
2. Remove the main power connection to heater from battery or pull fuse for a minimum of 20 seconds.
3. Using switch or standard timer control, turn the heater off.
4. Reinstall main heater power connection where previously disconnected.
Rectify the cause of the fault.
IMPORTANT: Heater fault codes can be read using PC Diagnostics, however, the heater lockout reset must be
manually performed using the procedure stated above.
If you have any questions, contact our technical support team at (800) 860-7866 or via email at:
.
Webasto Thermo & Comfort N.A., Inc. 38 www.techwebasto.com
Heater Maintenance
8. Heater Maintenance
8.1 Annual Maintenance
The Webasto heater requires a minimum of maintenance to operate.
To keep the Webasto Scholastic Heater™ in good working order, the following maintenance procedures should be
performed annually before each heating season:
NOTE: For major repairs and service parts, return to your authorized Webasto Specialist.
Enclosure Area
• Clean the heater and enclosure area of any accumulated debris or dust with compressed air.
• Inspect all components for wear and damage.
Electrical System
• Check all wiring harnesses for damage and corrosion, repair or replace if required.
• Check the condition of the batteries and the connections.
• Load test the batteries and replace if necessary.
NOTE: The heater will not function properly or to your satisfaction with weak batteries.
Exhaust System
• Check the exhaust system carefully for restrictions or corroded areas. Replace worn or damaged exhaust
components as necessary.
Fuel System
• Replace the fuel filter (prime) and inspect the fuel line for wear and damage. Repair or replace if necessary.
Burner System
• Swing open the burner head, clean the flame detection (photo eye), pull out the combustion chamber, inspect and
clean the inside area of the heat exchanger. Replace the fuel nozzle if necessary (annually). Reinstall the combustion
chamber and close up the burner head.
Operational Check
• Run the heating system for at least 15 minutes.
• Check all water and fuel connections for leakage. Check tightness of all hose clamps if necessary.
NOTE: Operate your Webasto heater at least once a month for 20 minutes.
www.webasto.us 39 Webasto Thermo & Comfort N.A., Inc.
Technical Data
9. Technical Data
Except where limit values are specified, the technical data refer to the usual heater tolerances of ±10% at an ambient
temperature of +20 °C (68 °F) and at the nominal voltage and conditions.
9.1 Scholastic Heater Data
Table 3. Technical Data
HEATER SCHOLASTIC
DESIGN Coolant heater with high-pressure nozzle
HEAT OUTPUT kW
(Btu/h)
13.0
(45,000)
FUEL Diesel #1, #2, Arctic and Kerosene
FUEL CONSUMPTION
l/h
(gal/h – US)
(gal/h – Imp.)
1.5
(0.4)
(0.3)
RATED VOLTAGE V 12
OPERATING VOLTAGE V 10-14
POWER CONSUMPTION OF HEATER
WITHOUT COOLANT CIRCULATION
PUMP Watt 60
PERMISSIBLE AMBIENT TEMPERATURE
DURING OPERATION:
HEATER, CONTROL UNIT, COOLANT
CIRCULATION PUMP - °C (°F)
– 40... + 60
(– 40... + 140)
PERMISSIBLE STORAGE TEMPERATURE:
CONTROL UNIT:
HEATER, COOLANT CIRCULATION
PUMP - °C (°F)
+ 85 max. (+ 185 max.)
– 40... + 85 (– 40... + 185)
MIN. CAPACITY OF COOLING SYSTEM
liter
(gal. – US)
(gal. – Imp.)
10
2.65
2.2
PERMISSIBLE OPERATING PRESSURE OF
THE COOLANT bar (psi) 0.4-2.0 (6-29)
CO
2
IN EXHAUST GASES % BY VOL. 10.5... 11.0
CO IN EXHAUST GASES % BY VOL. 0.2 max.
SMOKE NUMBER (BOSCH) 3.0 max.
DIMENSIONS OF HEATER L
INCL. CONTROL UNIT W
mm (inch) H
584 (23)
205 (8.1)
228 (9.0)
DIMENSIONS OF HEATER ENCLOSURE L
W
mm (inch) H
603 (23.75)
305 (12)
254 (10)
DIMENSIONS OF HEATER TRAY L
W
mm (inch) H
603 (23.75)
305 (12)
228 (9.0)
WEIGHT OF HEATER
INCL. CONTROL UNIT kg (lb) 15 (33)
WEIGHT OF HEATER AND TRAY
INCL. CONTROL UNIT kg (lb) 27 (60)
Webasto Thermo & Comfort N.A., Inc. 40 www.techwebasto.com
Technical Data
9.1.1 Scholastic Heater™ Dimensions
Figure 25: Scholastic Heater™ - dimensions
583.7
26
26
1
2
3
4
4
1 Space required for removal of
the overheat fuse
2 Fuel inlet connection - JIC #4
3 Space required for removal of
the combustion chamber
4 Space required to swing the
burner head open
www.webasto.us 41 Webasto Thermo & Comfort N.A., Inc.
Technical Data
9.2 Coolant Circulating Pump Data
Table 4.
9.2.1 Coolant Circulating Pump Dimensions
Figure 26: Coolant circulating pump assembly P/N 906017 - dimensions (inches)
CIRCULATING PUMP MP School Bus Pump
FLOW RATE l/h
(gal/m – US)
3400 - 4542
(15 - 20)
NOMINAL VOLTAGE 12
OPERATING VOLTAGE 10-14
POWER CONSUMPTION Watt 72
DIMENSIONS L
mm (inch) W
H
214 (8.42)
106 (4.16)
106 (4.16)
WEIGHT kg
(lb)
2.5
(5.5)
HOSE CONNECTION mm
(inch)
28.5
(1-1/8)
BLACK (NEGATIVE)
RED (POSITIVE)
4.80
3.25
1.60
2.00
4.76
8.42
2.25
3.08
DIA.
.57
.25
4.16
DISCHARGE
1-1/8 O.D.
MOTOR LEADS (2) #14 GA PRIMARY GPT
18” LONG FROM MOTOR
.75 DIA.
GROMMET
SUCTION
1-1/8 O.D.
.23 DIA.
THRU
1.00
Webasto Thermo & Comfort N.A., Inc. 42 www.techwebasto.com
Technical Data
9.3 Mounting Tray Dimensions
Figure 27: Mounting tray dimensions (inches)
23.75 in
(79.375 mm)
21.75 in
(552.45 mm)
9.75 in
(247.65 mm)
7.625 in
(193.675 mm)
12.0 in
(304.8 mm)
18.625 in
(473.075 mm)
22.5 in
(571.5 mm)
9.0 in
(228.6 mm)
1.5 in
(38.1 mm)
Ø 0.75 in
(19.05 mm)
Ø 1.375 in
(34.925 mm)
0.375 in
(9.525 mm)
Fuel Supply Port
Exhaust Tube Port
Ø 3.125 in
(552.45 mm)
Mounting Slots
4 Places
Electrical Connector
Location
www.webasto.us 43 Webasto Thermo & Comfort N.A., Inc.
Technical Service Bulletins / Product Information
10. Technical Service Bulletins / Product Information
Webasto Product N.A., Inc. s 15083 North Road s Fenton, Michigan 48430
For Technical Assistance in USA Call: (800) 555-4518 s In Canada Call: (800) 667-8900
Visit us on the Web at: www.techwebasto.com (North America) www.webasto.com (Global)
Page 1 of 3
Product Information
Description: NOI (NO OPERATOR INTERFACE) “WHITE” TIMER INSTALLATION / OPERATION
Category: Thermosystems
Document Number: PI007RC
Date Posted: 02/02/2007
Overview
The “White” timer is a 7-day NOI (no operator interface) timer. This means you can set this timer to specific needs
and the timer will do the rest. This timer has battery backup and will hold its memory if the vehicle battery is
disconnected and will recharge when 12 volt power is restored.
Installation
The timer should be installed in an area protected from the effects of weather and contamination. The timer can be
surface mounted on the vehicle instrument panel or inside the circuit panel (Bus applications) or any place convenient
and accessible.
The timer can be mounted using customer/installer supplied Velcro tape by
sticking one half of the Velcro to the timer and the other to a secu
re mounting
location. The timer can be mounted with screws in place of Velcro.
Connect the Webasto heater switching harness to the timer.
Refer to the wiring diagram below for directions.
After all connections are made, mount the new timer. Using customer/i
nstaller
supplied Velcro tape or screws.
Optionally, an On/Off toggle switch can be installed with the timer. The timer
will work without using the toggle switch however, it’s a nice option to have.
To mount the toggle switch, locate an appropriate mounting location and drill a
½” mounting hole. Refer to the wiring diagram on next page to, connect the
appropriate wires to the toggle
switch.
Wiring diagram - NOI Timer
5 12 Volt Positive
4 Optional
3 On Signal
2 Ground
1 12 Volt Positive
T1
X1
Legend
T1 Timer - 7-Day (NOI)
X1 9-Pin Duetsch Connector
C
A
D
B
J
E
F
G
H
Brown
Brown
Brown
Red Red
Red
BT
F5
Red
Green
Black
White
Red
Red
White
Black
Webasto Wiring Harness
Webasto Thermo & Comfort N.A., Inc. 44 www.techwebasto.com
Technical Service Bulletins / Product Information
Webasto Product N.A., Inc. s 15083 North Road s Fenton, Michigan 48430
For Technical Assistance in USA Call: (800) 555-4518 s In Canada Call: (800) 667-8900
Visit us on the Web at: www.techwebasto.com (North America) www.webasto.com (Global)
Page 2 of 3
Product Information
Description: NOI (NO OPERATOR INTERFACE) “WHITE” TIMER INSTALLATION / OPERATION
Category: Thermosystems
Document Number: PI007RC
Date Posted: 02/02/2007
Wiring diagram - NOI Timer with optional Toggle Switch
Setting the Timer
The timer is a 7-day NOI (no operator interface) timer. This means you can set this timer to specific needs and the
timer will do the rest. This timer has battery backup and will hold its memory if the vehicle battery is disconnected and
will recharge when 12 volt power is restored.
To set the timer clock:
Press and hold the “Clock” button and by pressing the “Hour” and “Min.” buttons set the clock appropriately. In the
upper left corner you will see the “AM” or “PM” sign.
Setting the timer On/Off functions:
Press the “Timer” button one time. You will see the screen now reads “1” “On” using the day button select the
Appropriate day or days. Look in the upper left hand corner for the “AM” or “PM” sign. Using the day button you can
select one or multiple days. After you have selected the proper day/days and set the appropriate on time, push the
“Timer” button once again. You should now see “1” “Off” using the day button select the appropriate days again.
BE SURE THE DAYS SELECTED MATCH THE SAME DAYS YOU SELECTED FOR TIMER “1” “ON”.
Now set the timer to the appropriate “Off” time. After you have set the timer functions need
ed, push the “Clock” this
will save your settings and return to the clock.
These steps can be repeated 6 more times giving you multiple on and off settings. It is very important that you set this
timer to the specific needs of each vehicle to optimize the heaters efficiency.
www.webasto.us 45 Webasto Thermo & Comfort N.A., Inc.
Technical Service Bulletins / Product Information
Webasto Product N.A., Inc. s 15083 North Road s Fenton, Michigan 48430
For Technical Assistance in USA Call: (800) 555-4518 s In Canada Call: (800) 667-8900
Visit us on the Web at: www.techwebasto.com (North America) www.webasto.com (Global)
Page 3 of 3
Product Information
Description: NOI (NO OPERATOR INTERFACE) “WHITE” TIMER INSTALLATION / OPERATION
Category: Thermosystems
Document Number: PI007RC
Date Posted: 02/02/2007
Operation in manual mode:
The largest button on the timer is the “Manual” button. At the bottom of the “LCD” screen you will see a small line
that moves as you push this button. Underneath the small line you will see the corresponding function “On” “Auto”
“Off”. The manual button can be used as a toggle switch to operate the heater or after you have programmed the
timer for automatic service, push the manual button until the line is over “auto” on the timer. The timer will now turn
the heater on and off at the times preset earlier.
NOTE:
The toggle switch will illuminate green when the heater has an “On” signa
l. If the toggle switch is in the
“Off” position and the timer has turned the heater on, the toggle will illuminate green. This is an easy
way to identify the heater is in operation. While the timer is “On” the toggle switch will NOT
operate
the heater. The toggle switch is a master switch whenever the timer is not in operation.
Safety Precautions:
s The heater must be switched off at filling stations and tank farms as a result of the risk of explosion.
s The heater may not be operated in enclosed spaces (such as garages) as a result of the risk of
poisoning and asphyxiation, even if a timer is used.
s Wherever inflammable vapors or dust may form (for example in the vicinity of fuel, carbon, wood
dust or cereal stores or the like), the heater mu
st be switched off as a result of the risk of explosion.
As with other devices whose activation is
automated, if a particular
application presents a risk should the heater be automatically activated,
and such a vehicle or application is equipped with a “power cut off”
type switch which prevents devices from activating automatically, then
this timer/heater should be wired into this “power cut off circuit” to
ensure automated activation of the heater does not occur.
WARNING
Warranty
Webasto Thermo & Comfort N.A., Inc. 46 www.techwebasto.com
Limited Non-Transferable Warranty
Webasto Thermo & Comfort North America, Inc. (hereinafter referred to as Webasto) warrants their heaters and heater
kits against defects in material and workmanship for two (2) years effective at the time of installation or vehicle
registration date for original equipment installation (OEM). This warranty period may not exceed three (3) years from
the original date of sale by Webasto. This warranty period may be superseded by written contractual agreements.
All models are limited to 2,000 maximum operating hours.
Replacement parts are covered for six (6) months or the remainder of the original warranty period, whichever is longer.
The intent of the Webasto warranty is to protect the original end-user of the heater from defects and provide free
repair and replacement of defective parts in the manner provided herein. During the warranty period, the exclusive
remedy will be for Webasto, at their discretion, to repair or replace those parts which are demonstrated to be defective
in material or workmanship.
While warranty is provided to the “original end-user”, it is to be administered and serviced through an authorized
Webasto dealer in accordance with the Webasto warranty policy or contractual agreement between Webasto and a
second party.
To locate the nearest Webasto authorized dealer for warranty service:
visit http://www.techwebasto.com or call (800) 860-7866 in USA, (800) 667-8900 in Canada.
The heater can be registered by visiting www.techwebasto.com or by
scanning the code.
A proof of purchase is required for all heaters that are not registered.
Notes
www.webasto.us 47 Webasto Thermo & Comfort N.A., Inc.
Your Notes
Webasto Thermo & Comfort N.A., Inc.
15083 North Road
Fenton, MI 48430
Technical Assistance Hotline
USA: (800) 860-7866
Canada: (800) 667-8900
www.techwebasto.com
www.webasto.us
Org. 10/2007 Rev. 07/2019 P/N 907511B
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Webasto DBW 2010 Instrucciones de operación
- Tipo
- Instrucciones de operación
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Indel Webasto Marine isotherm 101N0510 Manual de usuario
