Coolant Heater Thermo Thermo Thermo Thermo 90 90 90 90 S B (Gasoline) S D (Diesel) ST B (Gasoline) ST D (Diesel) Installation Manual – Improper installation or repair of Webasto heating and cooling systems can cause fire or the leakage of deadly carbon monoxide leading to serious injury or death. – Installation and repair of Webasto heating and cooling systems requires special Webasto training, technical information, special tools and special equipment.
Thermo 90 S / Thermo 90 ST Table of Contents Contents Page 1. Safety and General Information 1.1 1.2 5 Warning Symbols in this Installation Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Regulation for Installation in the Vehicle 2.1 2.2 2.3 2.4 2.5 2.6 2.
Table of Contents Thermo 90 S / Thermo 90 ST 13.Initial Start-up 34 14.Troubleshooting 35 14.1 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 14.2 Heater Interlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 14.2.1 Interlock Reset Procedure. . . . . . . . . . . . . . . . . .
Thermo 90 S / Thermo 90 ST Safety and General Information 1. Safety and General Information 1.1 Warning Symbols in this Installation Manual The purpose of safety symbols is to attract your attention to possible hazardous conditions. This manual 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.
Regulation for Installation in the Vehicle 2. Regulation for Installation in the Vehicle 2.3 2.1.1 2.1.2 2.2 Scope Subject to the provisions of paragraph 2.1.2, internal combustion heaters must be installed in accordance with the requirements contained in this Annex. The fuel filler neck must not be located in the passenger compartment and must have a tightly fitting cap to prevent any fuel leaks. 2.3.
Thermo 90 S / Thermo 90 ST 2.7.2 Regulation for Installation in the Vehicle 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. IMPORTANT! 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.
Purpose / Version Thermo 90 S / Thermo 90 ST 3. Purpose / Version 3.
Thermo 90 S / Thermo 90 ST Installation 4. Installation As a rule, installation in the engine compartment represents sufficient screening. Please contact the Webasto hotline in the event that radio interference occurs nevertheless. IMPORTANT! The water heater must be installed outside the passenger cabin. The requirements of the latest version of “Hazmat” must also be observed for the installation of the heater into vehicles used to transport hazardous substances. 4.
Installation Location Examples Thermo 90 S / Thermo 90 ST 5. Installation Location Examples Figure 1: Installation locations Webasto Product N.A., Inc. 10 www.techwebasto.
Thermo 90 S / Thermo 90 ST Mounting the Heater to the Vehicle 6. Mounting the Heater to the Vehicle 6.1 Allowable Mounting Positions 3 1 2 Coolant Direction Fuel Connection Figure 2: Allowable enclosure kit mounting positions, 1 and 2 only. Position 3 is not permissible. = Figure 3: Permitted installation positions for the Thermo 90 S / Thermo 90 ST heaters - Enclosure and Compact Kits = Figure 4: Permitted installation positions for the Thermo 90 S / Thermo 90 ST heaters - Compact Kits only www.
Mounting the Heater to the Vehicle Thermo 90 S / Thermo 90 ST Do not drill holes through top or bottom of vehicle frame flanges! CAUTION Do not weld vehicle frame or flanges! mm ) 80 /32” 5 (3mm ) 70 3/4” (2- Figure 5: Drill frame within the shaded area only! 310mm (12-13/64”) 80mm (3-5/32”) 70mm (2-3/4”) 150mm (5-29/32”) 23mm (29/32”) 45mm (25/32”) Figure 6: Mounting heater enclosure via back wall (Vertical or horizontal mounting) Webasto Product N.A., Inc. 12 www.techwebasto.
Thermo 90 S / Thermo 90 ST Mounting the Heater to the Vehicle 150mm 150mm 484mm 363mm 158mm 500mm Figure 7: Optional perpendicular mounting with bracket kit P/N 905822 or P/N 905838 (Freightliner style) Figure 8: Optional cross-frame mounting bar/clamp kit P/N 600055 (Also see Figure 1) www.webasto.us 13 Webasto Product N.A., Inc.
Connection to the Vehicle Cooling System Thermo 90 S / Thermo 90 ST 7. Connection to the Vehicle Cooling System 7.1 General Information The heater is connected to the vehicle cooling system as shown in Figures 10 through 15, depending on the type of heating system the vehicle is equipped with. The system must contain at least 6 litres (1.6 US Gal.) of coolant. The system must be filled with an antifreeze and water mixture as recommended by the vehicle manufacturer.
Thermo 90 S / Thermo 90 ST Connection to the Vehicle Cooling System 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 resetting temperature limiter to trip while the heater is in operation. 7.
Connection to the Vehicle Cooling System 2 Thermo 90 S / Thermo 90 ST 2 7 1 1. 2. 3. 4. 5. 6. 7. Coolant supply connection Vehicle heat exchangers Coolant pump Thermo 90 S / ST heater Coolant return connection Engine coolant pump Thermostat 6 4 5 3 Figure 12: System configured in series with rear heat exchanger in a “dual” circuit heating system. 2 2 7 1 1. 2. 3. 4. 5. 6. 7.
Thermo 90 S / Thermo 90 ST 11 2 Connection to the Vehicle Cooling System 2 8 7 9 1 9 6 4 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Coolant supply connection Vehicle heat exchangers Coolant pump Thermo 90 ST heater Coolant return connection Engine coolant pump Thermostat Automated control valve Wye connectors N/A Auxiliary heat exchanger 5 3 Figure 15: System configured with an additional auxiliary heat exchanger connected in “series / parallel” with rear heat exchanger circuit.
Fuel Supply Thermo 90 S / Thermo 90 ST 8. Fuel Supply 8.1 General Information The values for the maximum pressure at the fuel extraction point are shown in the table below and in Figure 17. Permissible fuel inflow height H At maximum pressure in fuel line 0.00 m (0.00 in.) 0.2 bar (2.9 PSI) 1.00 m (39.4 in.) 0.11 bar (1.6 PSI) 2.00 m (78.7 in.) 0.03 bar (0.44 PSI) Maximum fuel intake height S At maximum negative pressure in the fuel tank 0.00 m (0.00 in.) -0.10 bar (-1.45 PSI) 0.50 m (19.
Thermo 90 S / Thermo 90 ST 8.2 Fuel Supply Fuel Standpipe Installation To install the standpipe: This separate fuel pickup precludes any effect of pressure. 1. bore a 25mm (1”) hole through top of fuel tank (item G, Figure 18). 2. remove sharp burrs and smooth edges with emery cloth. 3. determine length of standpipe when installed. End should sit at least 25mm (1”) above tank bottom. Cut off excess standpipe at a 45 degree angle. Remove burrs. 4. loosely assemble items C, D, E, and F (Figure 18). 5.
Fuel Supply Thermo 90 S / Thermo 90 ST 7. bring standpipe up to horizontal and insert opposite shoulder under the tank hole. See Figure 20. 8. center standpipe in tank hole. See Figure 21. Figure 21: Standpipe installation - illustration 3 9. pull up on standpipe and tighten in place with the clamping nut (item A in Figure 22).
Thermo 90 S / Thermo 90 ST 8.3 Fuel Supply Fuel Lines 8.4 Only steel, copper and plastic lines made of plasticized, light and temperature-stabilized PA 11 or PA 12 (e.g. Mecanyl RWTL) pursuant to DIN 73378 may be used for the fuel lines. Fuel Metering Pump The fuel metering pump is a combined delivery, metering and shut-off system and is subject to certain installation criteria (see Figures 24 and 25).
Fuel Supply 8.4.2 Thermo 90 S / Thermo 90 ST Attachment The metering pump must be secured with a vibrationdamping mounting. Its installation position is limited as shown in Figure 24 and 25 in order to ensure effective automatic bleeding. As a result of the risk of corrosion, only genuine Webasto parts may be used for the plug connections between the metering pump and the metering pump wiring harness. 8.
Thermo 90 S / Thermo 90 ST Combustion Air Supply 9. 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 in that it cannot become clogged with dirt or snow and cannot suck in splashing water. IMPORTANT! The combustion air must be extracted using a combustion air line from a position that is as cool as possible and protected from splashing water.
Exhaust System Thermo 90 S / Thermo 90 ST 10. Exhaust System The exhaust pipe (internal diameter 38 mm) can be installed with a length of 0.5 m to 5 m (1.6 ft to 16 ft) and several bends totalling a maximum of 360° altogether. The minimum bending radius is 85 mm (3.35 inches). The exhaust muffler is essential and must be installed near the heater. The opening of the exhaust pipe must not point towards the front of the vehicle (see Figure 28).
Thermo 90 S / Thermo 90 ST Exhaust System 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.
Electrical Connections Thermo 90 S / Thermo 90 ST 11. Electrical Connections 11.1 Power / Control Harness 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. For sleeper and engine heating applications, Webasto recommends a four battery system for best results.
Thermo 90 S / Thermo 90 ST Electrical Connections 11.2 Connecting the Controls The heater can be switched on and off using the following Webasto controls: • Switch, see circuit diagrams in Figures 30, 32 and 34. • Timer, see circuit diagrams in Figures 31, 33 and 35. Heater Control Harness Connection Using a 12 or 24 Volt Switch 1 1. 2. 3. 4.
Circuit Diagrams Thermo 90 S / Thermo 90 ST 12. Circuit Diagrams 12.1 Thermo 90 S Circuit Diagram Legend The following Table applies to Figures 32 and 33. Digital timer P2: Connection X8 to Red jumper of switch harness results in continuous operation with immediate heating (recommended for trucks requiring sleeper heating) Item Designation Comment A1 Heater A2 Control module Connection X8 to vehicle ignition connection results in variable heating duration that can be programmed (10 min.
3 2 4 M1 1 X1 B1 GND 12V + 2 1 E B2 Black White Black White X2 X16 S1 DS 30 87 X3 2 1 M2 B3 87a Black Red 2 1 X4/X5/X6/X7 White 11 BT 9 7 5 3 1 F5 Black X8 Brown Red 1 Brown White X10 J H Brown Brown G Brown F Brown Red Red E A Red C White Red 2 Black White Brown D Violet B Red Red Green X12 C White Black B Green Violet 1 White 2 F3 A B C D E F F1 F2 X11 1 2 X12 1 2 X10 Brown A Red White Red Red Red X15 B X15 Brown Gra
H3 P2 X9 1 12 B1 H1 7 10 4 H6 8 2 11 M2 3 2 1 Brown Brown Red Yellow Gray Black Violet 4 8 5 7 2 1 4 3 X13 6 1 X14 2 BT White Red Black Brown Red F5 2 1 White C Red Red J Brown G Brown F E A Red C White D Violet B Black Brown 5 B 7 Violet 9 A White X12 X15 11 H Brown 1 Brown Brown Red Red Red Green Black 2 X4/X5/X6/X7 3 1 White M1 X3 X8 6 9 12 A B C D E F F1 F2 F3 3 Red White Red Red Red X2 2 1 X10 X9 Brown
Thermo 90 S / Thermo 90 ST Circuit Diagrams 12.2 Thermo 90 ST Circuit Diagram Legend Digital timer P2: Connection X14 to Red jumper of switch harness results in continuous operation with immediate heating (recommended for trucks requiring sleeper heating) The following Table applies to Figures 34 and 35. Item Designation Comment A1 Heater Connection X14 to vehicle ignition connection results in variable heating duration that can be programmed (10 min. to 120 min.); default setting 120 min.
3 2 4 M1 1 X1 B1 GND 12V + 2 1 E B2 Black White Black White X2 X16 S1 DS 30 87 X3 2 1 M2 B3 87a Black Red 2 1 X4/X5/X6/X7 White 11 BT 9 7 5 3 1 F5 Black X8 Brown Red 1 Brown White X10 J H Brown Brown G Brown F Brown Red Red E A Red C White Red 2 Black White Brown D Violet B Red Red Green X12 C White Black B Green Violet 1 White 2 F3 A B C D E F F1 F2 X11 1 2 X12 1 2 X10 Brown A Red White Red Red Red X15 B X15 Brown Gray
H3 P2 X9 1 12 B1 H1 7 10 4 H6 8 2 11 M2 3 2 Brown Brown Red Yellow Gray Black Violet 4 1 8 5 7 2 1 4 3 X13 6 1 X14 2 BT White Red Black Brown Red F5 2 1 Red Red J Brown G Brown F E A Red C White D Violet Black White C B Brown 5 B 7 Violet 9 A White X12 X15 11 H Brown 1 Brown Brown Red Red Red Green Black 2 3 1 White X4/X5/X6/X7 X8 6 12 F3 9 A B C D E F F1 F2 3 2 1 X10 X9 Brown M1 X3 Red White Red Red Red
Initial Start-up Thermo 90 S / Thermo 90 ST 13. Initial Start-up IMPORTANT! 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. NOTE: As a result of the low fuel consumption the heater must be switched on several times to fill the fuel line and prime the system. After you have installed the heater, bleed the water system and the fuel supply system carefully.
Thermo 90 S / Thermo 90 ST Troubleshooting 14. Troubleshooting 14.3 Diagnostic after a Fault Lock-out for the Thermo 90 S and Thermo 90 ST 14.1 General Information Check the fuses and plug connectors. 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 will be shut down. 14.3.
Technical Data Thermo 90 S / Thermo 90 ST 15. Technical Data 15.3 Fuel for Thermo 90 S and Thermo 90 ST (Diesel): 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. The diesel fuel specified by the vehicle manufacturer must be used. Heating oil may also be used as long as it complies to the normal quality available on the North American market. 15.
Thermo 90 S / Thermo 90 ST Heater Technical Data Operation Thermo 90 S Gasoline EC licensing symbol Thermo 90 S Diesel e1*2001/56*0005*__ Model Thermo 90 ST Diesel e1*2001/56*0005*__ e1*2001/56*0019*__ Water heater with Ferro-tec technology Heat output Max. regulating range 3830 BTU/hr – 26000 BTU/hr Fuel Fuel consumption Max. regulating range Gasoline Diesel 0.066 Gal/hr – 0.264 Gal/hr 0.29 Gal/hr 0.05 Gal/hr – 0.
Technical Data Thermo 90 S / Thermo 90 ST Thermo 90 S 3 5 ø20 45 ø39 29 ø5 ø6.5 100 99 78 88 126 134 120 89 95 4 ø30 1 2 ø20 ø38 48.6 98.6 = = 137.1 ø74 100 355 384 1 Combustion air intake 2 Exhaust outlet 3 Fuel inlet pipe 4 Coolant inlet 5 Coolant outlet 131 Thermo 90 ST 3 ø20 5 45 ø39 ø5 99 92 152 88 89 95 4 1 2 ø20 ø38 ø30 49 99 137 = ø74 = 100 352 131 381 Figure 38: Dimensions of the Thermo 90 S / Thermo 90 ST Heaters Webasto Product N.A.
Thermo 90 S / Thermo 90 ST Technical Data Enclosure Box www.webasto.us 39 Webasto Product N.A., Inc.
Additional Installation Accessories Thermo 90 S / Thermo 90 ST 16. Additional Installation Accessories Sleeper Pack - complete auxiliary heat exchanger kit. P/N 905670 Sleeper Pack - OEM HVAC to Webasto Coolant Heater Interface kits.
Thermo 90 S / Thermo 90 ST Notes NOTES www.webasto.us 41 Webasto Product N.A., Inc.
Notes Thermo 90 S / Thermo 90 ST NOTES www.webasto.us 42 Webasto Product N.A., Inc.
Thermo 90 S / Thermo 90 ST Notes NOTES www.webasto.us 43 Webasto Product N.A., Inc.
Webasto Thermo & Comfort N.A., Inc. 15083 North Road Fenton, MI 48430 Technical Assistance Hotline USA: (800) 860-7866 Canada: (800) 667-8900 Org. 01/2007 Rev. 4/2013 P/N 5000994A www.techwebasto.