Summary of Thermo 90 ST

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    – 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 tool...

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    Thermo 90 st table of contents www.Webasto.Us i webasto product n.A., inc. Contents page 1. Introduction 1 1.1 contents and purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 meaning of signal ...

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    Table of contents thermo 90 st webasto product n.A., inc. Ii www.Techwebasto.Com 8. Servicing work 25 8.1 general. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 8.2 work on the hea...

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    Thermo 90 st table of contents www.Webasto.Us iii webasto product n.A., inc. 9.2.7.1 removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 9.2.7.2 installation . . . . . . . . . . . . . . . . . . . . . . ....

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    Table of contents thermo 90 st webasto product n.A., inc. Iv www.Techwebasto.Com.

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    Www.Webasto.Us 1 webasto product n.A., inc. Thermo 90 st introduction 1. Introduction 1.1 c ontents and p urpose this repair shop manual is intended to assist trained personnel with repairing both the gasoline and the diesel versions of the thermo 90 st water heaters. 1.2 m eaning of s ignal w ords ...

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    Webasto product n.A., inc. 2 www.Techwebasto.Com introduction thermo 90 st 1.5 s uggestions for i mprovements and c hanges complaints, improvement suggestions or corrections relating to this workshop manual should be addressed to: webasto product north america, inc. Technical documentation group 150...

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    Www.Webasto.Us 3 webasto product n.A., inc. Thermo 90 st general description 2. General description thermo 90 st water heaters operate in conjunction with the vehicle’s own heating system and serve – to heat the cab, – to defrost the vehicle windows and – to preheat water-cooled engines. The water h...

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    Webasto product n.A., inc. 4 www.Techwebasto.Com general description thermo 90 st 2.1 c ombustion a ir f an the combustion air fan supplies the air required for the combustion process from the combustion air inlet to the burner insert. Figure 2: combustion air fan 2.2 h eat e xchanger in the heat ex...

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    Www.Webasto.Us 5 webasto product n.A., inc. Thermo 90 st general description 2.8 c ombustion p ipe the mixture of fuel and air burns in the combustion pipe, thus causing the heat exchanger to become hot. Figure 5: combustion pipe 2.9 c irculating p ump the circulating pump ensures that coolant is pu...

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    Webasto product n.A., inc. 6 www.Techwebasto.Com general description thermo 90 st this page for your notes..

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    Www.Webasto.Us 7 webasto product n.A., inc. Thermo 90 st functional description 3. Functional description 3.1 s witching o n the “operating indicator” on the digital timer lights up when the “immediate heating” button is pressed. Or when switching on with the switch, the operating indicator in the s...

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    Webasto product n.A., inc. 8 www.Techwebasto.Com functional description thermo 90 st figure 9: sequence of functions sequence of functions for thermo 90 st a. Glow pin b. Metering pump c. Combustion air fan d. Flame monitor e. Operation indicator light f. Circulating pump g. Vehicle fan switch on co...

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    Www.Webasto.Us 9 webasto product n.A., inc. Thermo 90 st functional description 3.5 m alfunctions 3.5.1 f ault l ock - out fuel is supplied for max. 240 seconds if the flame does not start to burn. Fuel is supplied for max. 240 seconds if the flame goes out during operation. The fuel supply is shut ...

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    Webasto product n.A., inc. 10 www.Techwebasto.Com functional description thermo 90 st this page for your notes..

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    Www.Webasto.Us 11 webasto product n.A., inc. Thermo 90 st technical data 4. Technical data except where limit values are specified, the technical data listed in the table refer to the usual heater tolerances of ±10% at an ambient temperature of +20 °c (+68 °f) and at the rated voltage and in rated c...

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    Webasto product n.A., inc. 12 www.Techwebasto.Com technical data thermo 90 st table 1. Technical data (page 2 of 2) co 2 in exhaust gas (permitted function range) maximum 10... 12.0% by volume co 2 adjustment values at approx. +20 °c and geographic altitude above sea level maximum 0 m (0 ft) 500 m (...

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    Www.Webasto.Us 13 webasto product n.A., inc. Thermo 90 st troubleshooting 5. Troubleshooting 5.1 g eneral this section describes how to identify and remedy faults on the thermo 90 st air heater. If a fault occurs, an error code will be output in the display of the timer. If the heater has a switch, ...

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    Webasto product n.A., inc. 14 www.Techwebasto.Com troubleshooting thermo 90 st 5.3 f ault i ndications on f ault l ock - out note: if the system is operated with a switch, the nature of the fault is indicated by a flashing code on an indicator light during the run-down time of the heater. After five...

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    Www.Webasto.Us 15 webasto product n.A., inc. Thermo 90 st troubleshooting table 3. Fault indications on fault lock-out (page 2 of 2) 5.3.1 p ermanent h eater f ault l ock - out a permanent fault lock-out is indicated by five short flash pulses with no long flash pulses following. Note: the permanent...

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    Webasto product n.A., inc. 16 www.Techwebasto.Com troubleshooting thermo 90 st 5.4 v isual c heck for a ssessing the b urner the burner and the evaporator in the heater display specific characteristics when they must be replaced or do not have any fault source. The criteria of a correct check are li...

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    Www.Webasto.Us 17 webasto product n.A., inc. Thermo 90 st troubleshooting 5.4.2 b ack wall with metal evaporator the pilot flame outlet opening (fig. 11) must be clear otherwise no start will occur. Remedy replace burner • cracks, flaking as well as black or other discoloration of the evaporator do ...

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    Webasto product n.A., inc. 18 www.Techwebasto.Com troubleshooting thermo 90 st this page for your notes..

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    Www.Webasto.Us 19 webasto product n.A., inc. Thermo 90 st functional tests 6. Functional tests 6.1 g eneral this section describes the tests conducted on the heater when it is installed and not installed to verify that it is in working order. Warning: the heater must not be operated in enclosed area...

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    Webasto product n.A., inc. 20 www.Techwebasto.Com functional tests thermo 90 st this page for your notes..

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    Www.Webasto.Us 21 webasto product n.A., inc. Thermo 90 st circuit diagrams 7. Circuit diagrams 7.1 g eneral the circuit diagrams (figs. 13 and 14) show the possible circuits for the thermo 90 st heater with – standard switch – standard timer 7.2 t hermo 90 st c ircuit d iagram l egend digital timer ...

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    Webasto product n.A., inc. 22 www.Techwebasto.Com circuit diagrams thermo 90 st figure 13: thermo 90 st with on/off switch - connection diagram (includes optional blower interface harness) x1 x8 x11 x10 x12 x15 x3 x4/x5/x6/x7 1 2 1 2 1 2 a b c eb 2 b3 m1 m2 b1 1 3 5 7 9 11 3 4 1 2 1 2 1 2 1 2 x2 0 0...

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    Www.Webasto.Us 23 webasto product n.A., inc. Thermo 90 st circuit diagrams figure 14: thermo 90 st with 7-day digital timer model 1531 - connection diagram 2 8 11 10 1 12 7 4 h3 p2 h1 h6 6 3 4 1 2 7 5 8 x1 x8 x13 x11 x10 x12 x15 x9 x3 x4/x5/x6/x7 3 6 9 12 1 2 1 2 1 2 a b c 3 4 6 7 8 5 1 2 eb 2 b3 m1...

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    Webasto product n.A., inc. 24 www.Techwebasto.Com circuit diagrams thermo 90 st this page for your notes..

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    Www.Webasto.Us 25 webasto product n.A., inc. Thermo 90 st servicing work 8. Servicing work 8.1 g eneral this section describes the servicing work that can be carried out on the heater when it is installed. 8.2 w ork on the h eater disconnect the main power cable from the vehicle’s battery before car...

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    Webasto product n.A., inc. 26 www.Techwebasto.Com servicing work thermo 90 st figure 15: installation example of a heater in a truck 7 1 2 3 4 5 6 8 9 10 11 12 13 14 15 1 thermo 90 st water heater 2 contr ol unit 3 cir culating pump 4 combus tion air intake 5 exhaus t outlet with muf fler 6 fuse blo...

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    Www.Webasto.Us 27 webasto product n.A., inc. Thermo 90 st servicing work 8.6 v isual i nspections and i nstallation i nstructions 8.6.1 c onnection to the v ehicle c ooling s ystem in thermostat circuits, only use thermostats which start to open at the heater should be installed in as low a position...

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    Webasto product n.A., inc. 28 www.Techwebasto.Com servicing work thermo 90 st 8.6.2.1 f uel e xtraction vehicles with diesel engines the fuel must be taken from the vehicle fuel tank or from a separate tank (figs. 17, 18 and 19). Figure 17: webasto fuel standpipe note: only use this style of standpi...

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    Www.Webasto.Us 29 webasto product n.A., inc. Thermo 90 st servicing work or vehicle fuel pump or if the ambient temperature is higher than the evaporation temperature of the fuel. The fuel extractor should not be located near the engine, as gas bubbles may form in the lines on account of heat radiat...

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    Webasto product n.A., inc. 30 www.Techwebasto.Com servicing work thermo 90 st it is advisable to install the metering pump in a cool place. The maximum ambient temperature must not exceed +20 °c (+68 °f) for gasoline and +40 °c (+104 °f) for diesel at any time during operation. The metering pump and...

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    Www.Webasto.Us 31 webasto product n.A., inc. Thermo 90 st servicing work the opening of the exhaust pipe must not point towards the front of the vehicle (see figure 24). The exhaust pipe opening must be located so that it cannot become clogged with snow and mud. Rigid pipes of unalloyed or alloyed s...

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    Webasto product n.A., inc. 32 www.Techwebasto.Com servicing work thermo 90 st this page for your notes..

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    Www.Webasto.Us 33 webasto product n.A., inc. Thermo 90 st repair 9. Repair 9.1 g eneral this section describes the repair work that may be carried out on the thermo 90 st heater after it has been removed from the vehicle. Any further dismantling will invalidate the warranty. Only use the spare parts...

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    Webasto product n.A., inc. 34 www.Techwebasto.Com repair thermo 90 st figure 25: replacing the circulating pump 1 sealing ring 2 circulating pump 3 clip 4 screw (2) 1 2 3 4.

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    Www.Webasto.Us 35 webasto product n.A., inc. Thermo 90 st repair 9.2.2 r eplacing the t emperature l imiter 9.2.2.1 r emoval note: the temperature limiter only has to be removed if it is being replaced with a new one. The function must be checked in the installed condition. 1. Remove the heater (see...

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    Webasto product n.A., inc. 36 www.Techwebasto.Com repair thermo 90 st figure 26: replacing the temperature limiter and temperature sensor 1 2 3 4 6 5 1 protective cap 2 clamp 3 temperature limiter 4 heat exchanger 5 round sealing ring 6 temperature sensor.

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    Www.Webasto.Us 37 webasto product n.A., inc. Thermo 90 st repair 9.2.4 r eplacing the c ombustion a ir f an 9.2.4.1 r emoval 1. Remove the heater (see 8.7.1.1). 2. Remove the screws (2, fig. 27). 3. Pull the combustion air fan (1) off the burner head (4) and remove together with the shaped sealing r...

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    Webasto product n.A., inc. 38 www.Techwebasto.Com repair thermo 90 st 9.2.5 r eplacing the b urner , f lame m onitor and g low p in 9.2.5.1 r emoval 1. Remove the heater (see 8.7.1.1). 2. Remove the combustion air fan (see 9.2.4.1). 3. Remove the screw (5, fig. 28) and washer (4). 4. Remove the nuts...

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    Www.Webasto.Us 39 webasto product n.A., inc. Thermo 90 st repair figure 28: replacing the burner, flame monitor and glow pin 1 13 12 10 9 11 1 burner 2 air swirl plate 3 burner head 4 washer 5 screw 6 glow pin 7 flame monitor 8 bar 9 insulation 10 nut (2) 11 grommet 12 grommet 13 grommet 8 7 6 3 2 4...

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    Webasto product n.A., inc. 40 www.Techwebasto.Com repair thermo 90 st 9.2.6 r eplacing the b urner h ead 9.2.6.1 r emoval 1. Remove the heater (see 8.7.1.1). 2. Remove the combustion air fan (see 9.2.4.1). 3. Remove the burner, flame monitor and glow pin (see 9.2.5.1). 4. Remove the mounting screw o...

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    Www.Webasto.Us 41 webasto product n.A., inc. Thermo 90 st repair 9.2.7 r eplacing the h eat e xchanger 9.2.7.1 r emoval 1. Remove the heater (see 8.7.1.1). 2. Remove the circulating pump (see 9.2.1.1). 3. Remove the temperature limiter (see 9.2.2.1). 4. Remove the temperature sensor (see 9.2.3.1). 5...

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    Webasto product n.A., inc. 42 www.Techwebasto.Com repair thermo 90 st this page for your notes..

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    Www.Webasto.Us 43 webasto product n.A., inc. Thermo 90 st product information 10. Product information no new or updated information available at this time..

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    Webasto product n.A., inc. 44 www.Techwebasto.Com product information thermo 90 st this page for your notes..

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    Thermo 90 st warranty w arranty c overage and l imitations webasto product north america, inc. (herein after referred to webasto) warrants their heaters and heater kits against defects in material and workmanship for two (2) years effective at the time of installationor vehicle registration date for...

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    W ebasto p roduct n.A., i nc . 15083 north road fenton, mi 48430 technical assistance hotline usa: (800) 860-7866 canada: (800) 667-8900 www.Techwebasto.Com www.Webasto.Us org. 03/2008 rev. 6/2012 p/n lit1301498a.