Thermo Top Z/C

List of Contents
1. Introduction 1.1 1.2 1.3 1.4
Scope and Purpose.....101 Meaning of Warnings, Cautions, and Notes...101 Additional Documentation to be used....101 Safety Information and Regulations....101 1.4.1 General Safety Notes....101

1.5 1.6

Legal Provisions for Installation....102 Corrections and Improvements....102
General Description 2.1 Combustion Air Fan Assembly....202 2.1.1 Combustion Air Fan.....202 2.2 2.3 2.4 Burner Housing.....202 Burner Insert....202 Control Unit/Heat Exchanger....203 2.4.1 2.4.2 2.4.3 2.4.4 2.5 2.6 Control Unit.....203 Temperature Sensor....203 Overheat Protection.....203 Heat Exchanger....203
Circulation Pump (Thermo Top C only)...203 Dosing Pump.....203
Functional Description 3.1 Functional Description Thermo Top Z (Supplementary Heater)...301 3.1.1 Switch On/Starting....301 3.1.2 Heating Operation....301 3.1.3 Switch Off/Deactivation....301 3.2 Functional Description Thermo Top C (Auxiliary Heater)...302 3.2.1 3.2.2 3.2.3 3.2.4 Switch On.....302 Heating Operation....302 Switch Off.....302 Auxiliary Heater in Supplementary Heater Function...303

Technical Data

5. Troubleshooting 5.1 5.2
General Fault Symptoms.... 501 Malfunctions.... 502 5.2.1 Error Lockout by Malfunction of Heater.... 502 5.2.2 Error Lockout due to Low or High Voltage... 502
Functional Checkouts 6.1 6.2 General..... 601 Functional Tests in the Vehicle.... 601 6.2.1 Heating Operational Test (Thermo Top C).... 601 6.2.2 Timer functional Test (Thermo Top C).... 602 6.2.3 Telestart T60 Functional Test (Thermo Top C)... 602 6.3 Repair Shop Level Testing.... 602 6.3.1 Components Testing.... 602
Circuit Diagrams 7.1 General..... 701
Servicing 8.1 8.2 8.3 8.4 8.5 8.6 General..... 801 Work on the Heater..... 801 Work on the Vehicle.... 801 Heater Test Run..... 801 Servicing.... 801 Visual Inspections and Installation Regulations... 801 8.6.1 Connection to Vehicle Cooling System... 801 8.6.2 Connection to Vehicle Fuel System... 803 8.6.3 Exhaust Line..... 804 8.7 Removal and Installation.... 805 8.7.1 Heater, Removal and Installation.... 805 8.7.2 Timer, Removal and Installation... 806 8.8 Initial Operation.... 806

9. Repair 9.1

General.....901 9.1.1 Work on Components after Disassembly...901
Disassembly and Assembly....902 9.2.1 9.2.2 9.2.3 9.2.4 Circulation Pump, Replacement (Thermo Top C)..902 Combustion Air Fan, Replacement....903 Burner Insert with Glow Plug/Flame Sensor, Replacement..905 Control Unit/Heat Exchanger with Burner Housing, Replacement..905
Packaging, Storage and Shipping 10.1 General.....1001
List of Figures List of Figures

901 902

Fault Symptoms..... 501 Automatic Switching Circuit for Thermo Top Z/C, 12 V Timer and Telestart T60.. 702 Inline Integration in the Engine Water Cooling Circuit... 801 Example for Heater Installation in Passenger Vehicle... 802 Fuel Supply..... 802 Webasto Fuel Tap..... 803 Pipe/Hose Connection..... 804 Dosing Pump, Installation Position.... 804 Exhaust Pipe Outlet, Installation Position.... 805 Timer, Removal and Installation..... 806 Replacement of Circulation Pump (Thermo Top C)... 902 Heater Disassembly.... 904

1 Introduction

1.4 Safety Information and Regulations

Introduction

Scope and Purpose
This repair shop manual is intended to support familiarised personnel in the repair of the water heaters Thermo Top Z and Thermo Top C of the fuel and Diesel types. As their appearance is identical or similar, the heaters are marked by type on their identification plate with "Benzin" (fuel) or "Diesel". The heaters may only be operated with the specified type of Diesel (or with fuel oil EL) and the appropriate type of electrical installation. Thermo Top C is a variant of Thermo Top Z with a circulation pump.
The general safety regulations for the prevention of accidents and the relevant operating safety instructions have to be observed at all times. "General Safety Regulations" beyond the scope of these regulations are detailed in the following. The specific safety regulations applicable to this manual are highlighted in the individual chapters by Warnings, Cautions, and Notes.
1.4.1 General Safety Notes
Within the scope of the StVZO (Road Licensing Regulations of the Federal Republic of Germany) "Design General Approvals" laid down by the Federal Office for Motor Traffic exist for the Water Heaters Thermo Top with the following official marks of conformity: ~~~ S292 for heater Thermo Top Z/C-B (fuel type) and ~~~ S289 for heater Thermo Top Z/C-D (Diesel type) Installation of the heater is to be performed in accordance with the installation instructions and must be checked in case of a) the vehicle type inspection in accordance with 20 StVZO b) the individual inspection in accordance with 21 StVZO or c) the examination in accordance with 19 StVZO performed by an officially authorised expert or examiner for road traffic, a vehicle inspector or a public servant as per section 7.4a of Annex VII to the StVZO. In the event of c) the installation must be certified on the acceptance certificate included in the copy of the General Operating License giving details about manufacturer type of vehicle and vehicle identification number. This validates the Design General Approval. The acceptance certificate must be kept with the vehicle. The heaters are cleared for heating the vehicle engine and the vehicle cabin. When using the heaters in vehicles not subject to the Road Licensing Regulations (StVZO) (e.g. ships), the applicable partially regional regulations must be observed. The use of the heater in "vehicles for the transportation of dangerous goods" (TRS) is not permitted. The heater may only be installed in vehicles or independent heating systems with a minimum coolant capacity of 4 litres. When checking the cooling water level proceed in accordance with the vehicle manufacturer's instructions. The water in the heating circuit of the heater must contain at least 10 % of a quality brand anti-freeze.

Burner Insert

Inside the burner insert fuel is distributed across the combustion pipe fuel cross section. Combustion of the fuel/air mixture takes place within the combustion pipe to heat the heat exchanger. Combustion air fan assembly The glow plug/flame sensor located in the burner insert ignites the fuel/air mixture during start of the heater. After start the glow plug/flame sensor operates in the flame sensor function. The glow plug/flame sensor designed as an electrical resistor is located in the burner insert opposite the flame side.

Burner Housing

The burner housing includes the coolant inlet coolant outlet exhaust outlet. The burner housing accommodates the burner insert and is combined with the control unit/heat exchanger as an assembly.

Burner insert

2.4 Control Unit/Heat Exchanger

2.4.4 Heat Exchanger

The heat exchanger transfers the heat generated by combustion to the coolant circuit.
The control unit/heat exchanger includes the control unit temperature sensor overheat protection heat exchanger connector terminal. CAUTION The control unit/heat exchanger and the burner housing represent an assembly and must not be disassembled.
Circulation Pump (Thermo Top C only)
The circulation pump ensures circulation of the coolant within the vehicle and heater coolant circuit. The pump is activated by the control unit and is in continuous operation.
Control unit Connector terminal

Circulation pump

Heat exchanger

2.4.1 Control Unit

The control unit is the central unit and ensures control and monitoring of combustion operation. The control unit is ventilated by means of a ventilation hose routed from the combustion air collector compartment of the burner.

Dosing Pump

The dosing pump is a combined delivery, dosing and shutoff system for the fuel supply of the heater out of the vehicle fuel tank.

2.4.2 Temperature Sensor

The temperature sensor senses the coolant temperature in the heat exchanger of the heater as an electrical resistance. This signal is routed to the control unit for processing.

Dosing Pump DP 2

2.4.3 Overheat Protection
Overheat protection, controlled by a temperature resistor, protects the heater against undue operating temperatures. Overheat protection responds at a water temperature in excess of 105 C and switches the heater off.

Page free for notes 204

3 Functional Description

3.1.2 Heating Operation

Fuel When the temperature rises to reach 72 C the heater switches to the energy saving part load operation. A rise in temperature up to 76.5 C causes the heater to enter a control idle period. This also happens when exceeding a total heating operating time of 76 minutes. After cool-down of the coolant to 71 C the heater resumes part load operation. Another rise in temperature to 76.5 C causes the heater to enter again the control idle period. A drop in the coolant temperature during part load operation due to an increased demand in heat will cause the heater to switch to full load operation at 56 C. Diesel Heating operation for the Diesel type heater is identical in the sequence of events. Should the coolant temperature drop during the control idle period to but not below 71 C within 900 seconds, a subsequent drop in the coolant temperature below 71 C causes the heater to perform a regular starting sequence into full load operation. A drop in the coolant temperature during part load operation due to an increased demand in heat will cause the heater to switch to full load operation at 65 C.

Functional Description

Functional Description Thermo Top Z (Supplementary Heater)

3.1.1 Switch On/Starting

Fuel When starting the vehicle engine the heater goes in standby. With a water circuit temperature below 60 C and an outside temperature below 5 C (option with outside temperature sensor) the starting sequence commences. The glow plug and the combustion air fan are activated. After 30 seconds the fuel dosing pump starts operation and combustion air fan operation is suspended for 3 seconds. Subsequently the combustion air fan speed is increased in a ramp within 57 seconds to nearly full load operation. After reaching full load fuel delivery within this period the glow plug is deactivated and the combustion air fan operation increased to full load. During the subsequent 45 seconds as well as in normal operation the glow plug functions as flame sensor to monitor the flame condition. After all these events the automatically controlled heating operation starts. In case of a no flame condition or a flameout, a restart is automatically initiated. If the no flame condition persists, fuel delivery is stopped and the heaters enters an error lockout with a run-down of the combustion air fan. Diesel When starting the vehicle engine the heater goes in standby. With a water circuit temperature below 60 C and an outside temperature below 5 C (option with outside temperature sensor) the starting sequence commences. The glow plug and the combustion air fan are activated. After 30 seconds the fuel dosing pump starts operation and combustion air fan operation is suspended for 3 seconds. Subsequently the combustion air fan speed is increased in two ramps within 56 seconds to nearly full load operation. After a stabilisation phase (constant speed) of 15 seconds the combustion air fan speed is again increased in a ramp within 50 seconds to nearly full load. After reaching full load fuel delivery the glow plug is deactivated and the combustion air fan operation increased to full load. During the subsequent 45 seconds as well as in normal operation the glow plug functions as flame sensor to monitor the flame condition. After all these events the automatically controlled heating operation starts. In case of a no flame condition or a flameout, a restart is automatically initiated. If the no flame condition persists, fuel delivery is stopped and the heater enters an error lockout with a run-down of the combustion air fan. A flameout during normal combustion operation causes an automatic restart.

3.1.3 Switch Off/Deactivation
When turning the engine off the heater is deactivated. Combustion stops and run-down commences. The combustion air fan first continues operation to cool the heater down (run-down) to be automatically switched off afterwards. NOTE The run-down time and the combustion air fan speed depend on the heater operating condition at the time of deactivation. Run-down time is for:
Fuel 168 seconds when deactivated in full load operation and 157 seconds when deactivated in part load operation. Diesel 175 seconds when deactivated in full load operation and 100 seconds when deactivated in part load operation. Dependent on the software variant implemented in the control unit there might be deviations from those run-down periods.
3.2 Functional Description Thermo Top C (Auxiliary Heater)

3.2.2 Heating Operation

3.2.1 Switch On
Fuel When operating the "instant heat" switch button the timer display shows or when operating the switch on the Telestart transmitter the operating indicator light on the transmitter flashes. This puts the heater in standly. The glow plug, the combustion air fan and the circulation pump are activated. After 30 seconds the fuel dosing pump starts operation and combustion air fan operation is suspended for 3 seconds. Subsequently the combustion air fan speed is increased in a ramp within 57 seconds to nearly full load operation. After reaching full load fuel delivery within this period the glow plug is deactivated and the combustion air fan operation increased to full load. During the subsequent 45 seconds as well as in normal operation the glow plug functions as flame sensor to monitor the flame condition. After all these events the automatically controlled heating operation starts. In case of a no flame condition or a flameout, a restart is automatically initiated. If the no flame condition persists, fuel delivery is stopped and the heaters enters an error lockout with a run-down of the combustion air fan. Diesel When operating the "instant heat" switch button the timer display shows or when operating the switch on the Telestart transmitter the operating indicator light on the transmitter flashes. This puts the heater in standly. The glow plug, the combustion air fan and the circulation pump are activated. After 30 seconds the fuel dosing pump starts operation and combustion air fan operation is suspended for 3 seconds. Subsequently the combustion air fan speed is increased in two ramps within 56 seconds to nearly full load operation. After a stabilisation phase (constant speed) of 15 seconds the combustion air fan speed is again increased in a ramp within 50 seconds to nearly full load. After reaching full load fuel delivery the glow plug is deactivated and the combustion air fan operation increased to full load. During the subsequent 45 seconds as well as in normal operation the glow plug functions as flame sensor to monitor the flame condition. After all these events the automatically controlled heating operation starts. In case of a no flame condition or a flameout, a restart is automatically initiated. If the no flame condition persists, fuel delivery is stopped and the heater enters an error lockout with a run-down of the combustion air fan. A flameout during normal combustion operation causes an automatic restart.

Fuel When the temperature rises to reach 72 C the heater switches to the energy saving part load operation. A rise in temperature up to 76.5 C causes the heater to enter a control idle period. This also happens when exceeding a total heating operating time of 76 minutes. The circulation pump, the vehicle's own heating air fan, and the operation indicator light remain on during control idle. After cool-down of the coolant to 71 C the heater resumes part load operation. Another rise in temperature to 76.5 C causes the heater to enter again the control idle period. A drop in the coolant temperature during part load operation due to an increased demand in heat will cause the heater to switch to full load operation at 56 C. Diesel Heating operation for the Diesel type heater is identical in the sequence of events. Should the coolant temperature drop during the control idle period to but not below 71 C within 900 seconds, a subsequent drop in the coolant temperature below 71 C causes the heater to perform a regular starting sequence into full load operation.

3.2.3 Switch Off

When turning the heater off by pushing the "instant heat" switch button ( in indicator panel extinguishes) or when operating the switch on the Telestart (flashing indicator on hand-held transmitter extinguishes) the vehicle heating air fan stops. Combustion terminates and run-down commences. The circulation pump and the combustion air fan first continue operation to cool the heater down (run-down) to be automatically switched off afterwards. NOTE The run-down time and the combustion air fan speed depend on the heater operating condition at the time of deactivation. Run-down time is for:
3.2.4 Auxiliary Heater in Supplementary Heater Function
3.2.4.1 Switch On When starting the engine the heater goes in standby (see 3.1.1). With the temperature of the water circuit below 60 C and the outside temperature below 5 C (option with external temperature sensor) the starting procedure is initiated. NOTE When operating in the supplementary heater function there will be no automatic trigger of the circulation pump and the vehicle's heating air fan. 3.2.4.2 Switch Off Turning the engine off deactivates the heater. Combustion is terminated and run-down commences. The combustion air fan however continues operation to cool the heater down (run-down) to be automatically switched off afterwards (see 3.1.3).

Remedy Check heater system integration in vehicle's fuel system. Check fuel lines for leakage, kinks or obstructions. If o.k. there is a heater internal leak. Remove heater and perform troubleshooting on repair shop level. Remove heater and perform troubleshooting on repair shop level. Remove heater and perform troubleshooting on repair shop level. Perform functional test of Timer (see 6.2.2) or of Telestart device (see 6.2.3). Replace or repair defective component. Inspect coolant hoses for leakage, kinks, loose hose clamps, etc. If o.k. there is a heater internal leak. Remove heater and perform troubleshooting on repair shop level. Check heater system integration in vehicle's fuel system. Check fuel line connections for leakage. If o.k. there is a heater internal leak. Remove heater and perform troubleshooting on repair shop level.
Heater does not achieve full load operation Continuous white smoke during combustion operation Heater cannot be switched off
Loss of coolant (dripping); heater develops smoke during combustion operation; smell of exhaust fumes extremely sweet Loss of fuel (dripping)

Fig. 501 Fault Symptoms

5.2 Malfunctions
Error Lockout Reset Thermo Top C with "Timer" After correction of the malfunction the error lockout is reset by switching the heater off and on again. In case of overheating an error lockout reset is achieved by removing fuse F1, 20A for at least 10 seconds. The fuse is not blown in case of an overheat condition. Error Lockout Reset Thermo Top C with "Telestart" After correction of the malfunction the error lockout is reset by switching the heater off and on again. In case of overheating an error lockout reset is achieved by removing fuse F1, 20A for at least 10 seconds. The fuse is not blown in case of an overheat condition. Error Lockout Reset Thermo Top Z A malfunction will cause an error lockout within the control unit. The error lockout condition may only be reset by disconnection of electrical power to the control unit (e.g. by removing fuse F1 for at least 10 seconds). The fuse must be removed with the engine running or within 60 seconds after turning the engine off.
5.2.1 Error Lockout by Malfunction of Heater
In case of a "no flame-up" condition fuel is delivered for a maximum of 180 seconds. In the event of overheating (temperature limiter responds) fuel delivery is stopped immediately. In all cases of malfunction (except for a defect on the combustion air fan) there will be an error lockout with a subsequent run-down. Dependent on the software variant implemented there might be deviations from the run-down times specified. NOTE An error lockout due to overheating does not display an indication.

l1 i 2 mm i 2 mm l2

Diesel
l1 + Im l1 1.2 m l2 5.8 m
l1 + l2 4.5 mm l1 0.5 mm lmm

Fig. 803 Fuel Supply 802

8.6.2 Connection to Vehicle Fuel System
In vehicles with carburettor or fuel injection including a return line the heater fuel system integration must be according to Fig. 802. Carburettor engines without return line must have the heater integrated in the fuel system's fuel supply line between fuel tank and vehicle fuel pump. NOTE A fuel supply line can normally be identified by the installation of a fuel filter. If the degassing vessel is included in the vehicle fuel system installation, the fuel tap must be located upstream of the degassing vessel. The following table lists the pressures permitted at the fuel tapping location. Permitted fuel feed height (H) m at max. permissible overpressure (bar) in fuel line Fuel Diesel 0.15 0.30 0.07 0.21 at max. permissible negative pressure (bar) in fuel tank Fuel Diesel -0.04 -0.35 -0.00 -0.31 -0.27
The fuel tap is to be mounted so that air or gas bubbles may escape towards the fuel tank. Air or gas bubbles may build up in the vehicle fuel line in case the carburettor or the fuel pump is leaking or if ambient temperatures exceed the fuel evaporation temperature. The fuel tap should not be located near the engine, as gas bubbles may build up due to the heat radiated by the engine resulting in malfunctions of combustion operation. When installing the heater in vehicles with fuel injection system, the fuel pump location, internal or external of the fuel tank, must be investigated. With a fuel pump located inside the fuel tank, fuel may be tapped only from the return line, ensuring that the return line is routed almost all the way down to the fuel tank floor. Otherwise the return line may be lengthened. NOTE If the fuel return line is provided with a check valve, a bypass must be provided. With a fuel pump located outside of the fuel tank the fuel tap may be located between tank and fuel pump. 8.6.2.1 Fuel Lines Fuel lines may only be steel, copper, or plastic lines made of unhardened, light and temperature stabilised PA 11 or PA 12 (e.g. Mecanyl RWTL) according to DIN 73378. As in most cases a permanently rising fuel line routing cannot be ensured, the inner diameter must not exceed a certain value. Starting from an inside diameter of 4 mm, air or gas bubbles accumulate resulting in malfunctions should the lines be descending or having sags. The diameters specified in Fig. 803 ensure no disturbing formation of bubbles. A descending line routing from the dosing pump to the heater should be avoided. Loose fuel lines must be secured in order to avoid sagging. The installation must ensure protection against stone impacts and undue temperatures (exhaust line).
0.00 1.00 Permitted suction height S (m)

0.00 0.50 1.00

Fuel tappings from the supply or return line may only use the special Webasto fuel tap.

NOTE Hose clamps must be torque tightened to 1.0 0.4 Nm.
Fig. 804 Webasto Fuel Tap
correct 8.6.2.3 Combustion Air Supply
A combustion air intake line is required. hose clamp The combustion air intake location must be protected against splash water. The combustion air line may routed in several bends (total of 270, smallest bending radius 50 mm). The maximum line length is 1000 mm. The combustion air must under no circumstances be taken in from rooms accommodating persons. If the heater is contained in an installation box, a vent hole of at least 3 cm2 is required. Should the temperature within the installation box exceed the permitted ambient temperature of the heater, the vent hole must be enlarged after consulting Webasto. The combustion air intake must be located so that clogging by contamination is not to be expected. The intake must not point in the direction of forward motion. When installing the heater in the vicinity of the vehicle fuel tank in a common installation compartment, the combustion air must be taken in from and the exhaust vented to the exterior. The line feedthroughs must be sealed against splash water.

wrong bubble bubble

Fig. 805 Pipe/Hose Connection
8.6.2.2 Dosing Pump The dosing pump is a combined delivery, dosing and shutoff system and is subject to certain installation criteria (Fig. 803 and 806). Concerning the installation location of the dosing pump it must be ensured that the maximum pressure at the tapping location is below the permissible value (see table of 8.6.2.). It is advantageous to mount the dosing pump in a cool location. The ambient temperature must never exceed + 20 C during operation. Dosing pump and fuel lines must not be installed in locations exposed to heat radiated by hot vehicle components. A heat shield is to be provided as necessary. The preferred installation location is near the tank. The dosing pump is to be attached with an anti-vibration mount. The installation position is limited according to Fig. 806 to ensure sufficient self-venting capability.

8.6.3 Exhaust Line

The exhaust line (inner diameter 22 mm) may be routed in several bends (total of 270, smallest bending radius 50 mm). The minimum line length is 500 mm, the maximum length is 1000 mm. The exhaust muffler is to be mounted near the heater, however at least 200 mm away from the heater. The exhaust muffler must not be installed near the combustion air intake. Heater operation without exhaust muffler is not permitted.

NOTE Accumulations of condensate in the exhaust line must be directly drained. A condensate drain hole (3 mm ) may be provided as required. Preferred The exhaust line outlet must not point in the direction of forward motion (Fig. 807) Rigid pipes of unalloyed steel with a minimum wall thickness of 1.0 mm or flexible hoses of alloyed steel only may be used as exhaust ducts.
Fig. 806 Dosing Pump, Installation Position
NOTE Collect coolant escaping in a vessel or prevent coolant from escaping by using squeezing tongs. 4. Loosen hose clamps and disconnect coolant hoses from heater. 5. Loosen heater from its mount. Exhaust flow direction nearly vertical 90 C 10 C 6. Loosen hose clamps, disconnect fuel line and close with suitable plug or any other means. 8.7.1.2 Installation
1. Locate heater for installation. 2. Connect fuel line to heater and secure with clamp. 3. Connect coolant hoses and secure with spring band steel clamps.
Fig. 807 Exhaust Pipe Outlet, Installation Position
4. Restore all electrical connections at connector terminal. 5. Connect antenna cable to Telestart receiver as required. 6. Reconnect battery terminals. 7. Bleed coolant circuit. 8. Bleed fuel system as required.

Removal and Installation

CAUTION In the heater installed condition only the circulation pump removal and installation is permitted should accessibility allow for such action (see 9.2.1).
8.7.1 Heater, Removal and Installation
8.7.1.1 Removal 1. Disconnect heater power supply by removing 20 A flat fuse (blue) from Webasto fuse holder. 2. Disconnect electrical connections from heater. Disconnect antenna cable to Telestart receiver T6 at screw type locking connector. 3. Open radiator cap for depressurisation, then close cap.
8.7.2 Timer, Removal and Installation
Timer removal and installation is to be performed in accordance with Fig. 808. For initial installation use drilling stencil. The electrical connection is shown in Section 7.

8.8 Initial Operation

After heater installation the coolant circuit as well as the fuel supply system must be carefully bled observing the relevant manufacturer's instructions. During the heater test run inspect all coolant and fuel connections for leakage and security. Should the heater during operation enter an error lockout condition, perform troubleshooting (see Section 5).
CAUTION During installation do not exert pressure on display.
NOTE Only the timer shown in Fig. 805 may be used in combination with the heater.

Fig. 808 Timer, Removal and Installation

9 Repair

Repair
This section describes the repairs that may be performed on the heaters Thermo Top Z and Thermo Top C when removed. Any further disassembly will void the warranty. After repairs a functional test must be performed.
9.1.1 Work on Components after Disassembly
CAUTION All gaskets located between disassembled components must always be discarded and replaced. 9.1.1.1 Cleaning All components disassembled must be cleaned. Sealing compound on components must be carefully and completely removed using suitable means.
9.1.1.2 Visual Inspection Inspect all components for damages (cracks, deformation, wear, etc.) and replace as required. Inspect connectors and wiring for corrosion, loose contacts, wrong crimping, etc. and repair as required. Inspect connector terminal for corrosion and contacts for security.
9.2 Disassembly and Assembly

9.2.1.2 Installation

9.2.1 Circulation Pump, Replacement (Thermo Top C)
9.2.1.1 Removal 1. Remove cover (4, Fig. 901) and disconnect electrical connector of circulation pump. 2. Loosen spring band steel clamp (5, Fig. 901). 3. Remove screw (7) and clamp (2). 4. Withdraw circulation pump (6) and remove spring band steel clamp (5). 5. Withdraw collar (1) as required. 6. Perform procedures on components after disassembly (refer to 9.1.1).
1. Slide spring band steel clamp (5, Fig. 901) onto hose end. 2. Position collar (1) on circulation pump (6) as required. 3. Locate circulation pump (6) for installation and secure with clamp (2) and screw (7) on combustion air fan (3). 4. Position spring band steel clamp (5). 5. Torque screw (7) with 3.5 0.3 Nm. 6. Connect circulation pump electrical connection and fit cover (4).
4 NOTE Circulation pump may also be mounted externally in vehicle. 3
Torque 3.5 Nm Collar Clamp Combustion air fan Cover Spring band steel clamp Circulation pump Screw
Fig. 901 Replacement of Circulation Pump (Thermo Top C) 902
9.2.2 Combustion Air Fan, Replacement
CAUTION In case of Thermo Top C the circulation pump must be removed first (see 9.2.1.1). 9.2.2.1 Removal 1. Carefully lever off cover (6, Fig. 902). 2. Disconnect electrical connector of combustion air fan. 3. Remove screws (11). 9.2.2.2 Installation

1. Replace gasket (12, Fig. 902) of combustion air fan (1) as required. 2. Position new gasket (2) on burner housing (3). 3. Slide combustion air fan (1) onto fuel pipe (9) to bring fan into installation position. 4. Secure combustion air fan (1) with screws (11). Torque tighten screws to 3.5 0.3 Nm. 5. Plug electrical connections of combustion air fan.
4. Withdraw combustion air fan (1) from burner housing (5) and fuel pipe (9). 5. Remove gasket (2) and discard. 6. Perform procedures on components after disassembly (refer to 9.1.1).
6. Install circulation pump as required (see 9.2.1.2). 7. Plug on cover (6) and engage.

Torque 3.5 Nm

Combustion air fan Gasket Burner insert Gasket Burner housing Cover
Control unit/heat exchanger Glow plug/flame sensor Fuel pipe Screw (4) Screw (4) Gasket
Fig. 902 Heater Disassembly 904
9.2.3 Burner Insert with Glow Plug/Flame Sensor, Replacement
CAUTION In case of Thermo Top C the circulation pump must be removed first (see 9.2.1.1). 9.2.3.1 Removal 1. Remove combustion air fan (see 9.2.2.1). 2. Push grommet of cable of glow plug/flame sensor (8, Fig. 902) out of burner housing (5). 3. Remove screws (10). 4. Withdraw burner insert (3) with glow plug/flame sensor (8) from burner housing (5). 5. Remove gasket (4) and discard. 6. Perform procedures on components after disassembly (refer to 9.1.1). 9.2.3.2 Installation 1. Position new gasket (4) on burner housing (5). 2. Position burner insert (3) for assembly and secure with screws (10). Torque tighten screws to 3.5 0.3 Nm. 3. Press grommet of glow plug/flame sensor cable into burner housing (5). 4. Install combustion air fan (see 9.2.2.2). 5. Install circulation pump as required (see 9.2.1.2).
9.2.4 Control Unit/Heat Exchanger with Burner Housing, Replacement
CAUTION In case of Thermo Top C the circulation pump must be removed first (see 9.2.1.1). 9.2.4.1 Removal 1. Remove combustion air fan (see 9.2.2.1). 2. Push grommet of cable of glow plug/flame sensor (8, Fig. 902) out of burner housing (5). 3. Remove screws (10). 4. Withdraw burner insert (3) with glow plug/flame sensor (8) from burner housing (5) and remove. 5. Remove gasket (4) and discard. 6. Perform procedures on components after disassembly (refer to 9.1.1). 9.2.4.2 Installation 1. Position new gasket (4) on burner housing (5). 2. Position burner insert (3) for assembly and secure with screws (10). Torque tighten screws to 3.5 0.3 Nm. 3. Press grommet of glow plug/flame sensor cable into burner housing (5). 4. Install combustion air fan (see 9.2.2.2). 5. Install circulation pump as required (see 9.2.1.2).

Page free for notes 906

10. Packaging, Storage and Shipping
10 Packaging, Storage and Shipping

10.1 General

The heater or its components shipped to Webasto Thermosysteme GmbH for testing or repair must be cleaned and packaged so that they are protected against damage during handling, shipping and storage. CAUTION When shipping a complete heater assembly it must be drained completely. No fuel is allowed to escape from a packaging or during shipping. Dummy plugs must be fitted to the fuel and coolant connector pipes.
Page free for notes 1002 02/2002

Thermo Top C Installation / Operation Manual Contents

Contents

1. Introduction 1.1 General Description.... 101 1.2 Legal Provisions.... 102 1.3 Meaning of Warning, Caution and Note... 102 2. Operating the Webasto Thermo Top C (TTC) 2.1 Switching On.... 2.2 Switching Off.... 2.3 Operation with Optional Digital Timer.... 2.4 Digital Timer Setting / Operating Instructions... 202 204
3. Technical Data 3.1 Technical Data.... 301 3.2 Heater Dimensions.... 302 3.3 Fuel Pump Dimensions.... 302 4. Installation 4.1 General Information.... 4.2 Installation Locations.... 4.3 Mounting the Heater... 4.4 Exhaust Pipe Connection.... 4.5 Combustion Air Supply.... 4.6 Plumbing the System.... 4.6.1 General Information... 4.6.2 Plumbing the Thermo Top C into The Coolant System.. 4.6.3 Contents - Engine Connections... 4.7 Fuel System.... 4.7.1 General Description... 4.7.2 Fuel System Limitations.... 4.7.3 Fuel Pump... 4.7.4 Fuel Standpipe.... 4.7.5 Fuel Line.... 4.7.6 Fuel Filter.... 4.8 Wiring Connections.... 4.8.1 General Information... 4.8.2 Power Connection to Battery... 4.8.3 Switch and Timer Connections... 4.8.4 Wiring Diagram - Thermo Top C (12 Volt) with On/Off Toggle Switch.. 4.8.5 Wiring Diagram - Thermo Top C (12 Volt) with Optional Digital Timer. 4.9 Initial Operation.... 423
5. Maintenance of the Heater 5.1 Annual Maintenance... 501
6. Basic Troubleshooting 6.1 General Information.... 6.2 General Failure Symptoms... 6.3 Heater Lockout Reset Procedure... 6.4 PC Diagnostics Kit....

602 602

List of Figures
411 Webasto Thermo Top C Coolant Heater.. Optional 7-Day Timer.... Heater Dimensions.... Fuel Pump Dimensions.... Installation Locations.... Permissible Heater Installation Positions.. Engine Block Preheating and/or Boost Heating.. Fuel System Limitations... Fuel Pump Mounting (DP 30).... Fuel Standpipe.... Fuel Line Connection.... On/Off Toggle Switch.... Optional 7-Day Digital Timer... Wiring Diagram - Thermo Top C with On/Off Toggle Switch.. Wiring Diagram - Thermo Top C with Optional Digital Timer... 422

List of Tables

Digital Timer Setting Instructions... Technical Data - Heater.... Technical Data - Circulating Pump... General Failure Symptoms... 301 601
Item No. 907512 Org. 9/1/99 Subject to modification.

Thermo Top C (TTC) 1.

Introduction

General Description

Fig. 101: Webasto Thermo Top C Coolant Heater 1. 2. 3. 4. 5. Control Unit. Combustion Air Fan Assembly Combustion Air Inlet Connection Pipe Coolant Circulating Pump Coolant Inlet Connection Pipe 6. 7. 8. 9. 10. Coolant Outlet Connection Pipe Fuel Inlet Connection Pipe Exhaust Outlet Pipe Combustion Chamber Heat Exchanger
The Webasto TTC is designed for Class 3-7 vehicles. This dynamic system allows you to preheat engines on or offsite. The TTC offers high performance with low power and fuel consumption. Approximately 2-hours of operation eliminates overnight idling for heating and the need for expensive electrical plug-ins. The compact design allows the heater to be frame rail or engine compartment mounted. The TTC is easy to install, maintain and operate. The universal package fits most of today vehicles.

Legal provisions

Thermo Top C (TTC)
Heater installation must be performed in accordance with the manufacturer`s installation instructions. Any deviation from these instructions are only permitted with the written approval from Webasto Thermosystems Inc. It is the dealer's responsibility to approve installations not performed by Webasto trained personnel. Installation not complying with the installation instructions release Webasto Thermosystems Inc. from any product liability. OEM installations must be approved by Webasto Thermosystems Inc.
Meaning of Warning, Caution and Note
WARNING! This heading is used to highlight that noncompliance with instructions or procedures may cause injuries or lethal accidents to personnel. CAUTION! This heading is used to highlight that noncompliance with instructions or procedures may cause damage to equipment. NOTE: This heading is used to highlight and draw specific attention to information.
Thermo Top C (TTC) 2. Operating the Webasto Thermo Top C (TTC)

Operating the Webasto

Before switching on theTTC, set vehicle heating system to the fiheat position and open any shut off valves. Depending on the type of control installed in the dashboard of the vehicle, the TTC can be operated by the following methods.

Switching On

Using the Optional Digital Timer:

Using a Switch:

Using the Switch: When the switch is used for turning ON the TTC, the operation indicator (toggle) lights up. Shortly thereafter, the heater begins operation and delivers heated coolant to the engine. Using the Optional 7-Day Digital Timer: 1. Set the timer up to 2 hr. before you want to start the engine. The heater will start up at set time. (See timer operating instructions.) Or switch fiinstan onf switch on your timer in the vehicle dash to ON The heater will start up. 2. When time is elapsed on your timer or engine preheat is no longer required, switch the TTC heater OFF The TTC will go through the after-run cycle. Pushing the fiinstan heatf button or when timer setting reaches desired start time, the fioperatio indicatorf on the timer will light, signaling that the heater is in operation. See section 2.3 fiOperatio with 7-Day Digital Timerf for complete instructions. NOTE: If heater is being switched on while the engine is warm only the circulating pump will run, coolant temperature must fall below 86 F. (30 C.) before heater starts. Startup Sequence: The coolant circulating pump, ceramic igniter and combustion air fan start operation and after approximately 60 seconds combustion starts (audible combustion sound). After the coolant temperature has reached the set point of 170 F (77 C) the TTC will automatically adjust its heat output to a lower operating range (part-load heat output). If the temperature of the coolant continues to rise and climb over 174 F (79 C) at the heater outlet, the heater will cycle off. When the temperature falls below 149 F (65 C) the heater will restart and repeat the heating cycle.

Operating the Heater

WARNING! Due to the danger of poisoning and asphyxiation the heater must not be operated in enclosed spaces such as garages or workshops without adequate exhaust extraction or ventilation. The Thermo Top C (TTC) will cycle on and off until: 1. The toggle switch is switched OFF 2. The fiinstan heatf button is pressed once again, signaling heater to shut off. 3. Time has elapsed on the timer. 4. The vehicle battery voltage drops below 9.6 V or the TTC runs out of fuel. WARNING! Explosion hazard! The heater must be switched fiOFF while refueling and at fueling stations. WARNING! Explosion hazard! Do not operate any Webasto heater in an area where toxic or explosive materials or fumes may be present.

Switching Off

Manually: When heating is no longer required, switch the TTC heater off by means of the toggle switch or by pressing the fiinstan heatf button on the optional timer. The indicator light turns off, combustion is extinguished followed by an after run cycle of approximately 90 seconds. Automatically: When the optional timer has reached the end of the timed cycle (up to 2 hours). NOTE: Restarting the heater during the after-run period is permitted.
Operation with Optional 7-Day Digital Timer
The timer enables you to preset the start time of the heater up to 7 days in advance. In addition, the timer enables the heater to be switched on and off instantly thereby eliminating the need for a separate switch. When the heater is in operation, the display and operation buttons of the timer are illuminated. The timer features a wake up alarm function. 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 of which only one can be activated at any one time.
Preselected Starting Times The preselected starting time is the time at which the timer switches the heater 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. 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 preselected 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. Setting the Digital Timer After the power has been connected, all symbols on the digital display will be flashing. The time of the day and the day of the week must be set. The Timer can be programmed in that all flashing symbols can be adjusted by means of the and buttons. If the buttons are not pressed within 5 seconds, the currently displayed time or function will be stored. When the and buttons are pressed for more than 2 seconds, the quick digit advance mode is activated. See table 201 on following page for setting reference or full instructions supplied with timer.

Fig. 201: Optional 7-Day Digital Timer
Digital Timer Setting / Operating Instructions
Manually: by pressing the button (continuous heating mode) Automatically: by programming the heater starting time
Switching the heater on Switching the heater off Setting time / day of the week Viewing the time Programming heater starting time
Manually: by pressing the button Automatically: after the programmed operating time has elapsed. With the heater running: by programming the remaining operating time. Press the button for more than 2 seconds - time of the day is flashing - and set the clock using the and buttons. After 10 seconds, day of the week begins flashing - set the day of the week in the same manner as the time. With the ignition switched off: press the button (bus wiring only).
Press the button - the memory location is flashing - using the and buttons set start of the heater operating time. After 10 seconds, day of the week begins flashing - set the day of the week on which the heater is to turn on. By repeatedly pressing the button, memory locations 2 and 3 can be programmed or the time display mode can be reached. Repeatedly press the preset time, press the memory location. button until the desired memory location is displayed. To erase the button several times until the time of the day is displayed instead of the
Recalling / erasing preset times Programming duration of operating time Setting the remaining operating time (Bus wiring Option) Setting the wake up time ( Digital Comfort Timer Only) Recalling / erasing the wake up time Remote control
The heater must be switched off. Press the button for 3 seconds - operating time is flashing and set the desired operating time (10 to 120 minutes) using the and buttons. Set the desired remaining operating time (1 to 120 minutes) using the and buttons. The remaining operating time refers to the time the heater still continues to remain in operation after the vehicle ignition is turned off. It can only be changed while the heater is in operation and the ignition switched off. A wake up time can only be programmed on the fi1531 comfort digital timer. The wake up time is not bound to a specific day of the week. Repeatedly press the button until the bell symbol appears on the display. Set the desired wake up time using the and buttons. The alarm clock turns off after 5 minutes or when one of the buttons is pressed. To recall the wake up time, repeatedly press the button until bell symbol appears on the display - read off wake up time. To erase the wake up time: press the button until the bell symbol is no longer visible on the display. Possible by means of an optional external signal.

Table 201: Digital Timer Setting Instructions

Thermo Top C (TTC) 3.

Technical Data
The following data is subject to the normal tolerance for heaters, if no tolerance is specified. This is approximately +/-10% in an ambient of 20 C at nominal voltage. Heater Thermo Top C (TTC) Diesel
Design Heat Rating: Input Output Fuel Fuel Consumption: Coolant heater with evaporator burner (Ferro-Tech Technology) - full load - partial load - full load - partial load 6.14 kW (20,960 Btu/hr) 3.1 kW (10,480 Btu/hr) 5.0 kW (17,200 Btu/hr) 2.5 kW (8,600 Btu/hr) Diesel #1 Diesel #2 and Arctic 0.61 l/hr (0.16 US gal/hr) 0.30 l/hr (0.08 US gal/hr) 12 Volts 9.6. 15 Volts
- full load - partial load
Rated Voltage Operating Voltage Rated Power Consumption Including Circulating Pump: - full load - partial load Maximum Permissible Ambient Temperature: Heater: - operation - storage Fuel Pump - operation Maximum Allowable Working Pressure (Coolant System) Capacity of Heat Exchanger Minimum Capacity of Coolant System Minimum Volume of Flow CO Content in Exhaust Gas Dimensions of Heater
46 Watts (3.8 Amps) 32 Watts (2.6 Amps)
- 40. +60 C (- 40.+140 F) - 40. +120 C (- 40.+248 F) - 40. +20 C (- 40.+68 F) 0.4. 2.5 bar (6.0. 36 psi) 0.15 Liters (.04 US gal) 4.0 Liters (1 US gal) 250 l/hr (66 US gal/hr) 8. 12.0 Vol.-% Length 232 mm (9.1 in) Width 105 mm (4.1 in) Height 163 mm (6.4 in) 3.2 kg (7.0 lbs.)

Weight

Table 301: Technical Data - Heater Circulating Pump
Volume Flow Against 0.13 bar (1.9 lbs.) Rated Voltage Operating Voltage Range Rated Power Consumption Dimensions of Circulating Pump Weight

Model U 4847

450 l/hr (2.0 US gal/min) 12 Volts 9.6. 15 Volts 14 Watts (1.16 Amps) L 95 mm x W 61 mm x H 61 mm (3.7f x 2.4f x 2.4fl 0.3 kg (.66 lbs)
Table 302: Technical Data - Circulating Pump

Heater Dimensions

Fig. 301: Heater Dimensions
Fig. 302: Fuel Pump Dimensions

Thermo Top C (TTC) 4.

Installation

General Information

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. WARNING! Asphyxiation risk! The heater must not be installed in either the driver's compartment or in the passenger area of the vehicle. NOTE: This manual does not cover all possible installations. For special applications use this manual as a general guideline only. Contact an authorized Webasto dealer or Webasto Thermosystems directly at USA: 1-800-555-4518 Canada: 1-800-667-8900

Installation Locations

CAUTION! Do not mount the heater directly to the engine! Heavy, constant vibration produced by the engine may interfere with the proper operation of the heater and lead to heater component damage.
Fig. 401: Installation Locations 1. Inside of the engine compartment in a splash protected area (Preferred). 2. On left/right side of the frame. 3. Inside under-step compartment.

Mounting the Heater

Fig. 402:
Permissible Heater Installation Positions
WARNING! Asphyxiation risk! DO NOT mount heater inside passenger, sleeper or storage areas. CAUTION! The openings of the water connecting pipes must never point in a downward direction in any installation position. Damage to heater will result due to trapped air in heat exchanger. CAUTION! The heater must not be installed in the immediate vicinity of or above hot vehicle parts. The heater must not be installed in the direct splash water area of the wheels. The heater should be mounted as low as possible in the vehicle to assure automatic purging of air from circulating pump and coolant lines. The coolant pump is not self-priming. Preferably, the heater should be mounted in the engine compartment. 1. Ensure adequate clearance for heater and components in existing enclosure or mounting area. 2. Carefully layout proposed heater mounting position and mark all holes for drilling keeping in mind location for exhaust, coolant lines and wiring access. Once all requirements are met, drill holes. 3. Mount heater and components according to your plan, fasteners for mounting heater are provided. NOTE: Heavy Duty frame rail bracket is available. Order under part number 901088.
4.4 Exhaust Pipe Connection
WARNING! Asphyxiation risk! Exhaust pipes must be so routed that the possibility of exhaust fumes entering the vehicle is unlikely. CAUTION! Route the exhaust pipe in such a way as to prevent touching or being directed toward any part of the vehicle that may be damaged by heat (i.e., brake lines, electrical wiring, hoses). NOTE: Additional flexible exhaust tubing is available from your Webasto Distributor or Dealer under part number 900126. One meter (39 inches) of flexible exhaust tubing has been supplied with the heater. Attach tube to the heater with exhaust clamp supplied. The exhaust tube should be routed in a gradual downward slope away from heater allowing condensation to drain. Secure exhaust tube to vehicle with fiP clip supplied. Keep exhaust tube at least 2 in. (50 mm) away from heat sensitive materials. The outlet opening of the exhaust tube must not point in the direction of travel to avoid any possible clogging caused by snow, mud or foreign materials.

Combustion Air Supply

WARNING! Never draw combustion air from inside the vehicle, or from areas where fumes or gases can accumulate. Drawing of combustion air from areas where people are present is strictly prohibited! A combustion air tube has been supplied with the heater. Looking at the tube, you will see one end has a staple holding the inner liner and outer casing together. The stapled end is the inlet end of the tube, the other end is to be attached to the heater. To attach tube to the heater, stretch the outer casing about an inch further than the inner liner. This will then slip over the inlet pipe of the heater and clamped in place. Do not make any bends immediately after the attachment point to the heater. Doing so may cause a restriction where the inner liner of the tube begins. Make all bends at least 3 inches away or further from heater connection point. The combustion air tube should be routed in a gradual downward slope away from heater allowing moisture to drain. The intake opening of the combustion air tube must not point in the direction of travel to avoid any possible clogging caused by snow, mud or foreign materials. Combustion air should always be taken from a clean area protected from road splash.

Plumbing the System

The TTC with coolant circulating pump must be mounted at least 6" (15 cm) below the lowest permissible coolant level of the vehicles cooling system. Minimum amount of coolant in the cooling system should be at least 1.0 US gal. (4.0 l). Independent heating systems require a minimum of 3.0 US gal. (12.0 l). A minimum of 10% of a good quality antifreeze should be maintained in the cooling system at all times. Heater and water pump fit 3/4f (19 mm) I.D. heater hose meeting SAE 20 R3 specifications. Silicone hose requires special hose clamps. WARNING! Burn risk! When working on the coolant system, allow the engine to cool down and open the radiator cap NOTE: Heater hose must meet SAE 20 R3 specifications. NOTE: Hose clamps must be tightened to 45 in/LB. (5 Nm) torque. Silicone hose requires special hose clamps.
4.6.2 Plumbing the TTC into The Coolant System
Fig. 403: Engine Block Preheating Engine Block Preheating: 1. Remove radiator pressure cap and release system pressure. 2. Drain coolant from engine. 3. Plumb the Webasto system as shown above. 4. Refill engine coolant as per engine manufacturer's recommendations and reinstall the radiator pressure cap.

Thermo Top C (TTC

4.6.3 Contents - Engine Connections
Caterpillar 3116..... 3176..... 3306..... 3408..... C-10/C-12....
Cummins B Series.... 411 C Series.... 412 Detroit Diesel Series 50.... 413 Series 55.... 413 Mack E6 / E7.... 414

Caterpillar

Thermo Top C(TTC)

Caterpillar 3116

Caterpillar 3176

Thermo Top C (T

Caterpillar 3306

Caterpillar 3408

Caterpillar C-10, C-12

Cummins

Cummins B Series

Cummins C Series

Detroit Diesel

Detroit Diesel Series 50

Detroit Diesel Series 55

Mack E6 / E7

Fuel System
The pump, fuel line and fuel standpipe are integral to the systems reliability and must be installed according to these instructions to ensure proper heater operation. 4.7.2 Fuel System Limitations
CAUTION! If the fuel tank is higher than the fuel pump, the top of the tank may not be more than 20" above the pump.
Fig. 404: Fuel System Limitations Maximum suction height (A) = 3' 3" (1m) Maximum suction length (A + B) = 6' 6" (2m) Maximum delivery length (C + D) = 19' 6" (6m) Maximum delivery height (D) = 9' 9" (3m)

Fuel Pump

The fuel pump MUST be mounted in a horizontal position in order to function correctly and deliver the proper quantity of fuel. Mount the fuel pump as close to the fuel source as practicable. Do not mount fuel pump near heat sources (exhaust pipes, hot coolant lines, etc.) Pay particular attention to the fuel line and pump limitations as covered in sections 4.7.2. and 4.7.3.
Fig. 405: Fuel Pump Mounting (DP 30) 4.7.4 Fuel Standpipe
The fuel is drawn from the vehicles fuel tank through a fuel standpipe. This standpipe can be utilized on vehicles with a spare threaded port, or if no threaded port is available, a 1" hole can be drilled into the tank and the universal tank boss installed as shown in figure 407. Keep the fuel standpipe 2" from the bottom of fuel tank. Fuel standpipe installation: 1. Cut or extend fuel standpipe to length, approx. 2" off fuel tank bottom. Angle the cut to prevent clogging. Remove burrs from cut end. 2. Install the universal fuel standpipe - use 1/4" or 1/2" spare port on fuel tank (if available) and install fuel standpipe or - drill 1" hole on top of tank (assemble tank-boss and fuel standpipe) and install assembled universal fuel standpipe 3. Connect fuel line from fuel metering pump to fuel standpipe using rubber connectors and clamps. 4. Route and secure fuel line from heater to fuel tank. NOTE: Fuel standpipe with universal tank boss can be installed from outside of tank. First assemble fuel standpipe and tank-boss and then insert at an angle through the 1f hole previously drilled into tank. Tighten down with nut provided. Do not over-tighten.

Fuel Standpipe

Fig. 406: Fuel Standpipe

Fuel Line

Fuel line, couplers and clamps are provided in the installation kit and are required for proper operation. CAUTION! Fuel line must be secured every 12f (30 cm) and kept away from hot exhaust and moving parts (drive shaft, wheels, etc. NOTE: Use supplied hose clamps to secure all fuel line connections. The TTC has been equipped with fuel line meeting the required specifications for proper operation. The inside diameter of this fuel line is 0.08f (2.0 mm) and must not be substituted for fuel line of a larger diameter. Doing so will result in improper fuel delivery and the formation of air pockets in the fuel system which will interfere with heater operation. Fuel line connections must be made as shown in figure 407, fuel line connection.
Fig. 407: Fuel Line Connection 4.7.6 Fuel Filter
The TTC heater may be equipped with a fuel filter. Fuel filters require changing at least annually and in cases of dirty fuel more often. NOTE: If heater is equipped with a fuel filter, change filter at least annually.

Wiring Connections

The control unit is equipped with low voltage protection, therefore it is imperative to keep the vehicle's battery connections and battery in good condition. NOTE: The Webasto heating system will not perform to your satisfaction with a weak battery. 4.8.2 Power Connection to Battery
Power harness connection instructions: 1. Route and secure wire harness from Webasto heater to battery box and cut harness to length. 2. Strip wires and crimp supplied ring tongue terminals to the positive (red) and negative (brown) wire leads. 3. Clean any corrosion from battery terminals. 4. Connect the leads to the battery terminals. 5. Protect connections with an anticorrosion compound designed for use with electrical connections and battery terminals. CAUTION! If welding is to be performed on the vehicle, the main battery cables must be disconnected from the battery to protect the electronic control unit. 4.8.3 Switch and Timer Connections
CAUTION! When drilling holes on the vehicle, do not drill into existing wiring or other mechanical components. Switch Installation: 1. Select a suitable location in the vehicle dash for the On/Off toggle switch. 2. Drill a 1/2f hole through the dash for the toggle switch. 3. Route harness between heater and dash, secure harness along its length with wire ties. If possible, use existing hole in fire wall or drill in suitable location. Protect the harness with a grommet at the fire wall. 6. Connect the terminals of the harness to the switch. See figure 408 on next page and wiring diagram figure 410 for reference.
Timer installation instructions: 1. Select a suitable location in the vehicle dash for the timer. 2. Temporarily affix timer drilling template to dash or see timer dimensions. 3. Cutout hole to dimensions on template or timer dimensions. 4. Mount timer bezel to dash. 5. Route harness between heater and dash, secure harness along its length with wire ties. If possible, use existing hole in fire wall or drill in suitable location. Protect the harness with a grommet at the fire wall. 6. Connect the terminals of the harness to the timer. See figure 409 below and wiring diagram figure 411 for reference. 7. Push timer into place in dash bezel.

Fig. 408: On/Off Toggle Switch
Fig. 409: Optional 7-Day Digital Timer
Wiring Diagram - Thermo Top C TTC) (12 Volt) with On/Off Toggle Switch
Fig. 410: Wiring Diagram - Thermo Top C (TTC) with On/Off Toggle Switch
Wiring Diagram - Thermo Top C (TTC) (12 Volt) with Optional Digital Timer
Fig. 411: Wiring Diagram - Thermo Top C (TTC) with Optional Digital Timer

Initial Operation

1. Check your installation for: - loose nuts and bolts. - exhaust system routing and clamp tightness. - loose hose clamps. - routing and securing of wiring and heater hoses. - kinked or pinched hoses. - routing and securing of fuel lines. - battery connection and polarity. 2. Top off or refill cooling system with coolant as per engine manufacturers recommendations. 3. Open shutoff valves. 4. Set heater valve to max. heat position and turn off Air Conditioning in cab and sleeper. 5. Start the vehicle engine and run it at a fast idle for 10 minutes to purge air from the TTC and the heat exchanger. While the engine is running check: - hose connections for leaks. - coolant level in the expansion tank and add coolant as needed. 6. Shut off the engine. 7. Switch on Webasto heater using the toggle switch or the fiInstan Heatf button on timer and check: - Switch toggle or instant heat button illuminates. - circulating pump in operation. - initiation of start up sequence. - successful start up and operation. 8. Temperature differential between water inlet and outlet should not exceed 10 C (18 F). NOTE: Coolant temperature must be below 86 F (30 C) to start up. NOTE: Installation with long fuel lines may need a second start attempt to prime the fuel lines. Cycle ON/OFF switch to reset control unit. NOTE: The engine temperature gauge may read lower than actual heater output temperature. This is due to the location of the temperature gauge sensor on the engine.
10. Switch OFF TTC heater. 11. Re-tighten hose clamps to 45 in/LB. (5 Nm) and inspect installation for leaks. 12. Complete the warranty card and send to Webasto Thermosystems. NOTE: Necessary information to complete warranty card and ensure full warranty coverage can be found on the heater name plate.

Thermo Top C (TTC) 5.

Maintenance of the Heater

Annual Maintenance

TheTTC heater requires a minimum of maintenance to keep in good operating condition. The following maintenance procedures should be performed annually before each heating season: NOTE For major repair and spare parts, return to your authorized Webasto Thermosystems Specialist. Enclosure Box and Heater - Clean the heater and enclosure box from any accumulated debris or dust with compressed air. - Inspect all components for wear and damage. Electrical System - Check wiring harnesses for damage, repair or replace if damaged. - Check the condition of the batteries and the connections. - Load test the batteries and replace if necessary. NOTE The heater will not function properly with weak batteries. Combustion Air System - Check for obstructions at air intake port. - Check air intake tube carefully for restrictions and damage. Repair or replace if damaged. Exhaust System - Check the exhaust system carefully for restrictions or corrosion. Replace damaged parts. Fuel System - Change fuel filter if equipped. Inspect fuel line for damage, restrictions, routing or loose connections. Repair or replace if damaged. Coolant System - Inspect all coolant lines and clamps for leakage, restrictions or damage. Repair or replace. - Inspect coolant circulation pump for leakage. Repair or replace if damaged. Operational Test - Run your heating system for at least 15 minutes. - Check water and fuel connections for leakage. Re-tighten hose clamps if necessary. NOTE Operate your Webasto at least once a month for 10 minutes.

Thermo Top C (TTC) 6.

Basic Troubleshooting
This section describes troubleshooting procedures for the TTC coolant heater. Troubleshooting is normally limited to the isolation of defective components. CAUTION Troubleshooting requires profound knowledge about structure and theory of operation of the heater components and may only be performed by skilled personnel. Before troubleshooting, check for and eliminate these defects: - blown fuses - fuel supply (plugged fuel filter) - corrosion on battery terminals, electrical wiring, connections and fuses - loose contact on connectors - wrong crimping on connectors
NOTE After any correction of a defect a functional test has to be performed in the vehicle.

General Failure Symptoms

Probable Cause
No combustion after start or automatic repeat start Flame extinguishes during operation Heater overheats
The following table lists possible failure symptoms. Failure Symptom
Coolant heater switches off automatically (Fault lockout)

Remedy

Switch off heater momentarily and switch on once again Switch off heater momentarily and switch on once again Check coolant lines for obstructions, closed valves and kinks. Check coolant level. Allow heater to cool down, reset over heat limiter, switch off heater momentarily and switch on once again Charge battery Switch off heater momentarily and switch on once again Check combustion and exhaust ducting for obstructions

Vehicle electrical system voltage too low Heater expels black fumes from exhaust Combustion air and/or exhaust ducting blocked
Table 601: General Failure Symptoms
Heater Lockout Reset Procedure
The TTC is designed with a lockout safety feature built in to the control unit. After 3 consecutive unsuccessful startup attempts, the heater will lock itself out from any further start attempts. The heater may also enter the lockout mode after experiencing an overheat condition. The following procedure will clear the lockout mode and reset the heater for normal operation: 1. Remove fuse F1 (15 Amp), refer to wiring diagram figure 411 for identification. Wait 10 seconds before reinserting. This is done to prepare the control unit for resetting. 2. Wait a further 10 seconds after reinserting fuse F1. Now turn the heater on using the On/Off switch or the fiinstan onf button of the optional timer. 3. Wait 10 seconds after turning the heater on and remove fuse F1 again. 4. Wait a further 30 seconds and then turn the heater off at the switch or optional timer. 5. Reinsert fuse F1 after waiting 3 to 10 seconds of shutting off the heater. 6. Wait a further 10 seconds and turn the heater back on again. The lockout mode should now be canceled and the heater operating normally.

PC Diagnostics Kit

CAUTION Diagnostics equipment is intended for use by Webasto trained personnel at authorized Webasto Distributor, Dealer and End User service facilities. It is possible to read and remove (reset) stored fault codes from the TTC memory. This is achieved through the use of a diagnostic interface kit connected to the TTC and an IBM compatible computer having the necessary software installed. The PC Diagnostic Interface Kit comes complete with connecting hardware, software and instructions. Also available are several interface connectors for use with Webasto heaters equipped with internal diagnostics capabilities such as theTTC. Order PC Diagnostics Kit under part number 9009064C. Kit does not include required adapter, please order adapter under part number 92566B. In addition to working with stored fault codes, the PC Diagnostics Kit allows you to do several other functions such as reading values while the heater is in operation or testing individual components. Printing out of fault codes is also available (User supplied printer required). For further capabilities and instructions for use with the TTC heater, see instruction manual supplied with the PC Diagnostics Kit.