Webasto Thermo 90, Workshop Manual

Page 1: ...Water Heaters 09 2001 Workshop Manual Thermo 90 Thermo 90 TRS Transport of hazardous goods Thermo 90 S Thermo 90 S TRS Transport of hazardous goods Type BW 80 Fuel Type DW 80 Diesel ...

Page 2: ... Tube 203 2 9 Circulation Pump 203 2 10 Control Unit 203 2 11 Dosing Pump 203 3 Troubleshooting 3 1 Switch on 301 3 2 Heating Operation 301 3 3 Control Operation 301 3 4 Switch off 301 3 5 Functions of the Heater in TRS Vehicles 301 3 6 Malfunctions 303 3 6 1 Switch off upon Failure 303 3 6 2 Diagnosis after Switch off upon Failure Thermo 90 303 3 6 3 Diagnosis after Switch off upon Failure Thermo...

Page 3: ... 3 Work on the Vehicle 801 8 4 Heater Test Run 801 8 5 Servicing 801 8 6 Visual Inspections and Installation Regulations 803 8 6 1 Connection to the Vehicle s Cooling System 803 8 6 2 Connection to the Vehicle s Fuel System 803 8 6 3 Dosing Pump 805 8 6 4 Fuel Filter 806 8 6 5 Combustion Air Supply 806 8 6 6 Exhaust Line 806 8 7 Removal and Installation 807 8 7 1 Heater Removal and Installation 80...

Page 4: ...902 9 2 2 Replacement of Circulation Pump 903 9 2 3 Replacement of Temperature Limiter 904 9 2 4 Replacement of Temperature Sensor 904 9 2 5 Replacement of Combustion Air Fan 906 9 2 6 Replacement of Burner Flame Sensor and Glow Plug 907 9 2 7 Replacement of Burner Head 909 9 2 8 Replacement of Heat Exchanger 910 10 Packaging Storage and Shipping 10 1 General 1001 ...

Page 5: ...ram Automatic Control for Thermo 90 S TRS 24 V 705 706 Circuit Diagram Automatic Control for Thermo 90 S TRS 24 V without Auxiliary Drive 706 801 Example for Heater Installation in Lorry 802 802 Fuel Supply 803 803 Webasto Fuel Tank Tap 804 804 Fuel Tapping from Plastic Tank tapping via fuel drain plug 804 805 Fuel Tapping from Plastic Tank tapping via fitting plate 804 806 Pipe Hose Connection 80...

Page 6: ... 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 Heater Thermo 90 with the following official marks of conformity S231 for water heater Thermo 90 and Thermo 90 S Fuel Type BW 80 S232 for water h...

Page 7: ...eater s Official Marks of Conformity and thus the vehicle s permit of operation 1 5 Legal Provisions for Installation For testing the heater in accordance with 19 20 or 21 of the StVZO the following regulations are to be observed in particular 22 a StVZO Testing is performed upon presentation of the operating and installation instructions of the manufacturer The year of the initial operation must ...

Page 8: ...ainers offered in the Webasto Accessories Catalogue are suitable for a maximum operating pressure of 0 15 bar overpressure All fuel containers offered in the Webasto Accessories Catalogue are subjected during manufacture to individual pressure testing with at least 0 3 bar overpressure The fuel containers must either be equipped with a vent cap or be ventilated in another way ventilation line Only...

Page 9: ...1 Introduction 104 Page free for notes ...

Page 10: ...eaters For an extremely high heating performance requirement preheating the maximum performance of 9 1 kW is available in case of Diesel operated water heaters for up to 2 hours after equipment activation The water heater Thermo 90 and Thermo 90 S basically consists of combustion air fan heat exchange burner insert with combustion tube circulation pump For control and monitoring a control unit ext...

Page 11: ...t exchanger dissipates the heat provided by combustion to the coolant circuit Heat Exchanger Thermo 90 S 1 2 3 4 5 6 7 8 9 10 11 1 Combustion Air Fan 2 Fuel Connection 3 Temperature Sensor 4 Temperature Limiter 5 Heat Exchanger 6 Inlet Coolant 7 Circulation Pump 8 Outlet Coolant 9 Outlet Exhaust 10 Inlet Combustion Air 11 Control unit may also be located externally in the vehicle Temperature Limit...

Page 12: ... The signals are routed to the control unit for processing The flame sensor monitors the flame operating condition over the complete duration of heater operation 2 8 Combustion Tube Inside the combustion tube the combustion of the fuel air mixture takes place heating up the heat exchanger 2 9 Circulation Pump The circulation pump provides for circulation of the coolant in the vehicle and heater ci...

Page 13: ...2 General Description Thermo 90 204 Page free for notes ...

Page 14: ...tages down to the lowest part load operation 3 3 Control Operation If the coolant temperature rises up to the control idle threshold the heater enters the control idle phase The circulation pump the vehicle s own blower and the operating indicator remain in operation during the control idle period After the coolant has cooled down to the precoded reactivation temperature the heater resumes operati...

Page 15: ...ff switch must only be operated in case of emergency as the heater is switched off without run down overheating possible Fig 301 Functional Sequence Functional Sequence for Thermo 90 Switch on Configuration Check Preheating 40 sec cycled Dosing Pump Priming 5 7 sec 1 Dosing Pump Part Load 1 4 Flame Sensor Take over Stabilisation Time Full Load Vehicle Blower On Control Range Control Idle Flame Sen...

Page 16: ...fault there will be an error lock out Reset by switch off and reactivation of the heater In case of overheating the knob of the temperature limiter has to be reset after the unit has cooled down CAUTION To avoid damage to the component do not attempt to reset the temperature limiter by force while hot 3 6 2 Diagnosis after Switch off upon Failure Thermo 90 When operated with switch or triple timer...

Page 17: ...Glow plug open or short circuit F 10 Overheating F 11 Circulation pump open or short circuit When operated with switch the type of error lock out condition is indicated by an operation indicator light flash code while the heater is in run down After five short signals the following long flash pulses are counted 1x No start after 2 start attempts 2x Flame out during operation repeated 5 3x Voltage ...

Page 18: ...Thermo 90 3 Functional Description 305 Page free for notes ...

Page 19: ...ax control range 2 0 7 6 kW 9 1 kW 1 8 7 6 kW Type of fuel Benzin Diesel Fuel consumption max control range 0 25 1 0 l h 1 1 l h 0 19 0 9 l h Nominal voltage 12 Volt 12 or 24 Volt 1 Operating voltage range 10 15 Volt 10 15 or 20 30 Volt Rated power consumption with circulation pump without vehicle blower max control range 37 W 83 W 90 W 37 W 83 W Permitted ambient temperature Heater operation stor...

Page 20: ...4 Technical Data Thermo 90 402 Page free for notes ...

Page 21: ...as to be performed in the vehicle before switch the heater off and on again 5 2 General Failure Symptoms The following table Fig 501 lists possible general failure symptoms Fig 501 General Failure Symptoms NOTE In many cases the probable cause of failure may be the burner Perform a visual inspection according to 5 4 Failure Symptom Failure Symptom Remedy Heater switches off automatically No combus...

Page 22: ...mbustion air exhaust duct Check combustion air exhaust duct for foreign matter and clean as required Burner Clean burner or replace as necessary 2 Flash pulses flame out during operation Fuel supply Check fuel level Check fuel filter Bleed fuel system Burner Clean burner or replace as necessary 3 Flash pulses low voltage Electrical power supply Check battery Check electrical connections 4 Flash pu...

Page 23: ...e no start Remedy Carefully remove any contamination e g with a wire of 1 5 mm diameter Remove glow plug first Fig 503 Visual Inspection Burner Real Wall Failure Symptom Failure Symptom Remedy 8 Flash pulses combustion air fan defective Wiring Check wiring for damage open connections or short circuit Combustion air fan defective Replace combustion air fan 9 Flash pulses glow plug defective Wiring ...

Page 24: ...urner The air bores Fig 505 in the combustion chamber must not be coked Coked air bores may cause a no start or insufficient combustion Remedy Removal of coke deposits by careful scraping 5 4 4 Burner Assembly The cables of glow plug and flame sensor must be routed as shown in Fig 503 The screwed connection of the housing and combustion chamber must be secure Fig 505 Housing and combustion chamber...

Page 25: ...er the following readings should be obtained Glow plug 12 Volt red 24 Volt green Resistance at 25 C 0 3 0 6 Ω 1 3 1 44 Ω Test current 5 mA 5 mA 6 3 3 Flame Sensor Resistance Test During electrical testing of the flame sensor using a digital multimeter the following readings should be obtained Cold test Resistance at 25 C 2 6 3 4 Ω Test current 5 mA Hot test Resistance at 800 1000 C 12 15 Ω ceramic...

Page 26: ...6 Functional Tests Thermo 90 602 Page free for notes ...

Page 27: ...ipment TRS equipment without auxiliary drive Fig 701 shows the pin assignment X1 for Thermo 90 and Thermo 90 S CAUTION The poles must not be looped or reversed as some components are controlled by negative polarity Fig 701 Pin Assignment 7 8 9 10 11 12 6 5 4 3 2 1 1 Glow Plug 2 Temperature Limiter 3 Flame Sensor 4 Temperature Sensor 5 Circulation Pump 6 Combustion Air Fan 7 Combustion Air Fan 8 Ci...

Page 28: ...rmostat E Glow Plug F1 Fuse 20 A Flat Fuse SAE J 1284 F2 Fuse 5 A Flat Fuse SAE J 1284 F3 Fuse 20 A Flat Fuse SAE J 1284 H1 Symbol for Heating in Display Operation indication in item P H3 Light Symbol illumination in item P H4 LED max 20 mA Flame indication option K1 Relay in item A2 Master relay K2 Relay in item A2 for circulation pump K5 Relay for vehicle blower K6 Relay only required for batter...

Page 29: ...sor B2 Temperature Sensor B3 Temperature Limiter B4 Room Thermostat E Glow Plug F1 Fuse 20 A Flat Fuse SAE J 1284 F2 Fuse 5 A Flat Fuse SAE J 1284 F3 Fuse 20 A Flat Fuse SAE J 1284 H2 Light in item S4 Operation indication max 2 W H4 LED max 20 mA Flame indication option K1 Relay in item A2 Master relay K2 Relay in item A2 for circulation pump K5 Relay for vehicle blower M1 Motor Combustion air fan...

Page 30: ...or B2 Temperature Sensor B3 Temperature Limiter B4 Room Thermostat E Glow Plug F1 Fuse 20 A Flat Fuse SAE J 1284 F2 Fuse 5 A Flat Fuse SAE J 1284 F3 Fuse 20 A Flat Fuse SAE J 1284 H1 Symbol for Heating in Display Operation indication in item P1 or P2 H3 Light Symbol illumination in item P1 or P2 H6 LED red in item P2 Illumination instant heat switch standby indication on indication K5 Relay for ve...

Page 31: ...E Glow Plug F1 Fuse 20 A Flat Fuse SAE J 1284 F2 Fuse 5 A Flat Fuse SAE J 1284 F3 Fuse 20 A Flat Fuse SAE J 1284 H2 Light in item S4 Operation indication max 2 W H5 Lamp at least 1 2 W On indication conveyor equipment K5 Relay for vehicle blower M1 Motor Combustion air fan M2 Motor Circulation pump M3 Motor Vehicle blower S4 Switch ON OFF S5 Isolation Switch 1 pole or 2 pole Emergency off switch e...

Page 32: ...1 Flame Sensor B2 Temperature Sensor B3 Temperature Limiter B4 Room Thermostat E Glow Plug F1 Fuse 20 A Flat Fuse SAE J 1284 F2 Fuse 5 A Flat Fuse SAE J 1284 F3 Fuse 20 A Flat Fuse SAE J 1284 H2 Light in item S4 Operation indication max 2 W K5 Relay for vehicle blower M1 Motor Combustion air fan M2 Motor Circulation pump M3 Motor Vehicle blower S4 Switch ON OFF S5 Isolation Switch 1 pole or 2 pole...

Page 33: ...rotection When performing extensive repairs on the heater a complete removal is advisable After work on the heating circuit a coolant mixture consisting of water and anti freeze must be replenished in accordance with manufacturer instructions followed by a careful bleeding of the heating circuit When performing repairs requiring a relocation of the installation position the relevant installation i...

Page 34: ...llowing servicing should be performed to maintain the heater s functional reliability Clean heater exterior prevent the ingress of water Examine electrical connections for corrosion of contacts and for security Check exhaust combustion air lines for damage and for foreign matter and contamination Check fuel lines and fuel filter for leakage Check coolant circuit and circulation pump for leakage Ch...

Page 35: ...ting System 2 Blower Switch Vehicle Heating System 3 Relay for Vehicle Blower 4 Timer 5 Fuse Box in Vehicle 6 Check Valve with Drain Hole 7 T Junction 8 Vehicle Engine 9 Heater Unit 10 Circulation Pump 11 Water Pump 12 Radiator 13 Regulating Valve 14 Control Unit 15 Exhaust Muffler 16 Dosing Pump 17 Combustion Air Intake Line 18 Thermostat Cable Loom Fuel Line Exhaust Line Coolant Circuit ...

Page 36: ... slippage NOTE Hose clamps must be torqued to 1 5 Nm clamps previously in use or to 5 0 Nm new wide clamps Prior to first operation of the heater or after replacement of the coolant bleed the cooling circuit Heater and lines have to be installed so that a static venting is guaranteed Insufficient venting during heating operation may cause failure due to overheating Proper venting is indicated by a...

Page 37: ...r engines without return line must have the heater integrated in the fuel supply between the vehicle s fuel tank and fuel pump NOTE A fuel supply line can normally be identified by an installed fuel filter If an exhalation vessel is installed in the vehicle s fuel system fuel tapping must be upstream of the exhalation vessel For fuel tapping from the supply or return line only the specific Webasto...

Page 38: ...tly 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 802 ensure a non accumulation of air bubbles A descending line routing from the dosing pump to the heater should be avoided Loos...

Page 39: ...mbustion air inlet must not be located above the exhaust outlet NOTE The combustion air intake line is to be routed in a downwards direction If this is not possible a water drain hole 4 mm Ø must be provided at the lowest point If the heater is located near the fuel tank in a common installation compartment combustion air must be taken in from and the exhaust routed to the exterior The feed throug...

Page 40: ...n heater Thermo 90 S with control unit flanged to combustion air fan reconnect connectors X12 and X13 to control unit 5 Connect plug of cable loom to heater 6 Plug on top cover and arrest 7 Reconnect battery terminal leads 8 Bleed fuel supply system 9 Bleed coolant circuit 8 7 2 Replacement of Circulation Pump NOTE The procedure for replacement of the circulation pump is identical with the heater ...

Page 41: ...Thermo 90 8 Servicing 809 Page free for notes ...

Page 42: ...mponents afterDisassembly CAUTION All gaskets located between disassembled components must always be replaced and discarded 9 1 1 1 Cleaning All disassembled components must be cleaned 9 1 1 2 Visual Inspection Examine all components for damages cracks deformation wear etc and replace as necessary Examine connectors and wiring for corrosion loose contacts wrong crimping etc and repair as necessary...

Page 43: ...m connector 3 Using removal tool screw driver end press down relevant locking tab and keeping tab depressed withdraw cables from connector 9 2 1 2 Making Electrical Connections 1 Slide cable into relevant contact pocket until locked 2 Using removal tool screw driver end insert lock wedge in connector and press in until locked 3 Fit top cover Fig 901 Electrical Connections Thermo 90 Lock Wedge Lock...

Page 44: ...Fig 902 2 Bring circulation pump 2 in assembly position and secure using clamp 3 and screws 4 3 Torque screws 4 to 3 Nm 10 4 Make electrical connections see 9 2 1 2 5 Install heater see 8 7 1 2 Fig 902 Replacement of Circulation Pump Thermo 90 NOTE One of the newer models Thermo 90 shown Older models have the cable of the temperature limiter located on the side Heater Thermo 90 S may have the cont...

Page 45: ...ully in place Only then will the temperature limiter be in proper installation position If clip does not audibly engage clean seat of the temperature limiter on the heat exchanger clean groove on heat exchanger ensure that the locking cams are present on both sides of the spring Renew temperature limiter if necessary 2 Fit protective cap 1 and secure with clamp 2 3 Torque tighten hose clamp with 1...

Page 46: ...perature Limiter 4 Heat Exchanger 5 O Ring 6 Temperature Sensor NOTE One of the newer models Thermo 90 shown Older models have the cable of the temperature limiter located on the side Heater Thermo 90 S may have the control unit located on the combustion air fan not affecting the replacement of the temperature limiter and temperature sensor ...

Page 47: ...tion NOTE Locate packing ring 3 Fig 904 properly do not squeeze 1 Bring combustion air fan 1 with new profiled packing ring 3 in assembly position and secure with screws 2 2 Torque tighten screws 2 with 3 Nm 10 NOTE On heater Thermo 90 S with flanged control unit install control unit as required 3 Make electrical connections see 9 2 1 2 4 Install heater see 8 7 1 2 Fig 904 Replacement of Combustio...

Page 48: ...1 9 2 6 2 Installation 1 Locate swirl ring 2 Fig 905 on burner 1 2 Carefully and fully insert flame sensor 7 and glow plug 6 into burner against stop and slide grommets 11 and 12 down slots in housing of combustion tube 3 3 Position burner 1 and grommet 13 in burner head 3 CAUTION When performing the following step ensure that cables of flame sensor 7 and glow plug 6 are routed as shown in figure ...

Page 49: ...r Head 4 Washer 5 Screw 6 Glow Plug 7 Flame Sensor 8 Bracket 9 Insulation 10 Nut 2 11 Grommet 12 Grommet 13 Grommet NOTE One of the newer models Thermo 90 shown Older models have the cable of the temperature limiter located on the side Illustration is also applicable for heater Thermo 90 S 11 12 6 7 8 9 10 13 1 3 5 4 2 ...

Page 50: ...d exhaust outlet pipe can still be aligned during installation in vehicle 1 Insert burner head 1 Fig 906 into heat exchanger 3 align as necessary and secure with V clamp 2 2 Torque attachment screw of V clamp to 3 Nm 10 as required 3 Install burner flame sensor and glow plug see 9 2 6 2 4 Install combustion air fan see 9 2 5 2 5 Install heater see 8 7 1 2 Fig 906 Replacement of Burner Head Thermo ...

Page 51: ...move burner head see 9 2 7 1 8 Remove connector and connector housing 9 Perform procedures on components after disassembly see 9 1 1 9 2 8 2 Installation 1 Clip connector housing onto heat exchanger and engage connector in connector housing 2 Install burner head see 9 2 7 2 3 Install burner flame sensor and glow plug see 9 2 6 2 4 Install combustion air fan see 9 2 5 2 5 Install temperature sensor...

Page 52: ...cleaned and packaged so that they are protected against damage during handling transportation and storage CAUTION Should a complete heater assembly be shipped it must be totally emptied When packaging or shipping it must be ensured that no fuel or coolant is able to escape The coolant pipe joints are to be sealed with plugs In storage ambient temperatures detailed in Section 4 must not be exceeded...

Page 53: ...10 Packaging Storage and Shipping Thermo 90 1002 Page free for notes ...