Webasto Thermo 90 ST User manual

Wasserheizgeräte
Water Heaters
Chauffages à eau
Einbauanweisung
Installation Instructions
Instructions de montage
Thermo 90 S
Thermo 90 ST
Thermo 90 S (Benzin) (Petrol) (Essence)
Thermo 90 S (Diesel) (Gas-oil)
Thermo 90 S-ADR (Gefahrguttransport)
(Transport of hazardous goods)
(Transport de marchandises dangereuses)
Thermo 90 ST (Benzin) (Petrol) (Essence)
Thermo 90 ST (Diesel) (Gas-oil)
Thermo 90 ST-ADR (Gefahrguttransport)
(Transport of hazardous goods)
(Transport de marchandises dangereuses)
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Das unsachgemäße Einbauen oder Reparieren von Webasto Heiz- und Kühlsystemen kann Feuer
verursachen oder zum Austritt von tödlichem Kohlenmonoxid führen. Dadurch können schwere oder
tödliche Verletzungen hervorgerufen werden.
Für den Einbau und die Reparatur von Webasto Heiz- und Kühlsystemen bedarf es eines
Webastotrainings, technischer Dokumentation, Spezialwerkzeuge und einer Spezialausrüstung.
Versuchen Sie NIEMALS, Webasto Heiz- oder Kühlsysteme einzubauen oder zu reparieren, wenn Sie
das Webastotraining nicht erfolgreich abgeschlossen und dabei die notwendigen technischen
Fähigkeiten erworben haben und die für einen sachgerechten Einbau und Reparatur nötigen
technischen Dokumentationen, Werkzeuge und Ausrüstungen nicht zur Verfügung stehen.
Befolgen Sie IMMER alle Webasto Einbau- und Reparaturanleitungen, und beachten Sie alle
Warnhinweise.
Webasto übernimmt keine Haftung für Mängel und Schäden, die auf einen Einbau durch ungeschultes
Personal zurückzuführen sind.
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.
To install and repair Webasto heating and cooling systems you need to have completed a Webasto
training course and have the appropriate technical documentation, special tools and special equipment.
NEVER try to install or repair Webasto heating or cooling systems if you have not completed a Webasto
training course, you do not have the necessary technical skills and you do not have the technical
documentation, tools and equipment available to ensure that you can complete the installation and
repair work properly.
ALWAYS carefully follow Webasto installation and repair instructions and heed all WARNINGS.
Webasto rejects any liability for problems and damage caused by the system being installed by
untrained personnel.
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 1 Friday, March 8, 2013 4:26 PM

Thermo 90 S / Thermo 90 ST
I
Inhaltsverzeichnis
1 Gesetzliche Bestimmungen für den Einbau . . . . . . . . . . . . 1
2 Verwendung / Ausführung . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Einbau . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 Einbaubeispiele . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 Anschluss an das Kühlsystem des Fahrzeuges . . . . . . . . 7
6 Brennstoffversorgung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7 Brennluftversorgung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8 Abgasleitung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
9 Elektrische Anschlüsse . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
10 Schaltpläne . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
11 Erstinbetriebnahme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
12 Störungen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
13 Technische Daten . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Table of contents
1 Statutory regulations governing installation . . . . . . . . . . 35
2 Use / version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4 Examples for installation . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5 Connection to the vehicle cooling system . . . . . . . . . . . . 41
6 Fuel supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
7 Combustion air supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
8 Exhaust pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
10 Circuit diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
11 Initial start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
12 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
13 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
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1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 3 Friday, March 8, 2013 4:26 PM

Thermo 90 S / Thermo 90 ST Statutory regulations governing installation
35
1 Statutory regulations governing installation
1.1. Statutory regulations governing installation
Thermo 90 S heaters have been type-tested and approved in
accordance with EC Directives 2001/56/EC (heater) and 72/245/EEC
(EMC) and Thermo 90 ST in accordance with ECE-R 122 (heater) and
ECE-R 10 (EMC) with the following permit numbers:
e1 00 0005 (Thermo 90 S, heater)
e1 03 1173 (Thermo 90 S, EMC)
E1 00 0217 (Thermo 90 ST, heater)
E1 03 4881 (Thermo 90 ST, EMC)
Primarily the regulations of Annex VII of the Directive 2001/56/EG and
Part I and Annex 7 of the directive ECE-R 122 must be observed for the
installation.
NOTE:
The provisions of these Directives are binding within the territory
governed by EU Directive 70/156/EEC and/or EC/2007/46 (binding
for new vehicle types as of 29/04/2009) and should also be
observed in countries in which there are no special regulations!
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 spare parts. This will result in the invalidation of the type
approval for the heater and therefore of its homologation / EC- or ECE
type licence.
1.2. Extract from directive ECE-R 122 Part I and Annex 7
Start of extract.
Part I
5.3 Vehicle Installation Requirements for Combustion Heaters and
for Electric Heaters
5.3.1 Scope
5.3.1.1 Subject to paragraph 5.3.1.2, heaters shall be installed according
to the requirements of paragraph 5.3.
5.3.1.2 Vehicles of category O ha ing liquid fuel heaters are deemed to
comply with the requirements of paragraph 5.3.
5.3.2 Positioning of heater
5.3.2.1 Body sections and any other components in the icinity of the hea-
ter must be protected from excessi e heat and the possibility of fuel or oil
contamination.
5.3.2.2 The heater shall not constitute a risk of fire, e en in the case of
o erheating. This requirement shall be deemed to be met if the installation
ensures an adequate distance to all parts and suitable entilation, by the
use of fire resistant materials or by the use of heat shields.
5.3.2.3 In the case of M2 and M3 ehicles, the combustion heater must
not be positioned in the passenger compartment. Howe er, an installation
in an effecti ely sealed en elope which also complies with the conditions
in paragraph 5.3.2.2 may be used.
5.3.2.4 The label referred to in Annex 7, paragraph 4, or a duplicate, must
be positioned so that it can be easily read when the combustion heater is
installed in the ehicle.
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Statutory regulations governing installation Thermo 90 S / Thermo 90 ST
36
5.3.2.5 E ery reasonable precaution should be taken in positioning the
heater to minimize the risk of injury and damage to personal property.
5.3.3 Fuel supply
5.3.3.1 The fuel filler must not be situated in the passenger compartment
and must be pro ided with an effecti e cap to pre ent fuel spillage.
5.3.3.2 In the case of liquid fuel heaters, where a supply separate from that
of the ehicle is pro ided, the type of fuel and its filler point must be clearly
labelled.
5.3.3.3 A notice, indicating that the heater must be shut down before
refuelling, must be affixed to the fuelling point. In addition a suitable
instruction must be included in the manufacturer’s operating manual.
5.3.4 Exhaust system
5.3.4.1 The exhaust outlet must be located so as to pre ent emissions from
entering the ehicle through entilators, heated air inlets or opening
windows.
5.3.5 Combustion air inlet
5.3.5.1 The air for the combustion chamber of the heater must not be
drawn from the passenger compartment of the ehicle.
5.3.5.2 The air inlet must be so positioned or guarded that blocking by
rubbish or luggage is unlikely.
5.3.6 Heating air inlet
5.3.6.1 The heating air supply may be fresh or re-circulated air and must
be drawn from a clean area not likely to be contaminated by exhaust fu-
mes emitted either by the propulsion engine, the combustion heater or any
other ehicle source.
5.3.6.2 The inlet duct must be protected by mesh or other suitable means.
5.3.7 Heating air outlet
5.3.7.1 Any ducting used to route the hot air through the ehicle must be
so positioned or protected that no injury or damage could be caused if it
were to be touched.
5.3.7.2 The air outlet must be so positioned or guarded that blocking by
rubbish or luggage is unlikely.
5.3.8 Automatic control of the heating system
5.3.8.1 The heating system must be switched off automatically and the
supply of fuel must be stopped within fi e seconds when the ehicle’s
engine stops running. If a manual de ice is already acti ated, the heating
system can stay in operation.
ANNEX 7
ADDITIONAL REQUIREMENTS FOR COMBUSTION HEATERS
7 Warning light
7.1 A clearly isible tell-tale in the operator’s field of iew shall inform
when the combustion heater is switched on or off.
End of extract.
NOTE:
Contrary to point 5.3.2.3 the heater must also not be installed in the
passenger cabin of class M1 and N vehicles. However, an installation in
an effectively sealed envelope which also complies with the conditions
in paragraph 5.3.2.2 may be used.
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Thermo 90 S / Thermo 90 ST Statutory regulations governing installation
37
1.3. Extract from directive ECE-R 122 Annex 9
Start of extract.
Additional pro isions applicable to certain ehicles as specified in the ADR.
3. Technical Provisions
3.1 General (EX/II, EX/III, AT, FL, OX and MEMU vehicles)
3.1.1 [1] The combustion heaters and their exhaust gas routing shall be de-
signed, located, protected or co ered so as to pre ent any unacceptable
risk of heating or ignition of the load. This requirement shall be considered
as fulfilled if the fuel tank and the exhaust system of the appliance conform
to the following pro isions:
- Any fuel tanks for supplying the appliance shall meet the following
requirements:
a) In the e ent of any leakage, the fuel shall drain to the ground
without coming into contact with hot parts of the ehicle or
the load;
b) Fuel tanks containing petrol shall be equipped with an effec-
ti e flame trap at the filler opening or with a closure enabling
the opening to be kept hermetically sealed.
- The exhaust system as well as the exhaust pipes shall be so directed
or protected to a oid any danger to the load through heating or
ignition. Parts of the exhaust system situated directly below the fuel
tank (diesel) shall ha e a clearance of at least 100 mm or be pro-
tected by a thermal shield.
3.1.2 The combustion heater shall be switched on manually. Programming
de ices shall be prohibited.

Combustion heaters using gaseous fuels are not permitted.

3.3.1 The combustion heaters shall be put out of operation by at least the
following methods:
a) Intentional manual switching off from the dri er’s cab;
b) Stopping of the ehicle engine; in this case the heating de ice
may be restarted manually by the dri er;
c) Start up of a feed pump on the motor ehicle for the
dangerous goods carried.
[1] Compliance with this paragraph shall be erified on the completed e-
hicle.
End of extract.
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Use / version Thermo 90 S / Thermo 90 ST
38
2 Use / version
2.1. Use of the water heaters
The Webasto water heater is used in connection with the vehicle's own
heating system
– to heat the cab,
– to defrost the vehicle windows and
– to preheat water-cooled engines.
The water heater operates independently of the engine and is
connected to the cooling system, the fuel system and the electrical
system of the vehicle.
The Thermo 90 S and Thermo 90 ST heaters differ from each other in
their component plug and in the fact that they have different control
modules.
2.2. Versions
2.2.1. Thermo 90 S version
Thermo 90 S petrol
Water heater for "petrol" fuel
Thermo 90 S diesel
Water heater for "diesel" fuel
The water heaters are designed for 12 V (Thermo 90 S petrol) and for
12 or 24 V (Thermo 90 S diesel).
2.2.2. Thermo 90 ST version
Thermo 90 ST petrol
Water heater for "petrol" fuel
Thermo 90 ST diesel
Water heater for "diesel" fuel
The water heaters are designed for 12 V (Thermo 90 ST petrol) and for
12 or 24 V (Thermo 90 ST diesel).
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Thermo 90 S / Thermo 90 ST Installation
39
3 Installation
IMPORTANT
– The heater must not be installed in the vehicle interior.
– The requirements of the latest version of the ADR must also be
observed for the installing the heater into vehicles used to transport
hazardous substances.
NOTE:
If the vehicle manufacturer has issued instructions, they must be
followed.
3.1. Installation site / Installation position
The heater must be installed in as low a position as possible to allow the
heater and circulating pump to be bled automatically. This is particularly
important as the circulating pump is not self-priming.
3.2. To install the heater
The heater must be secured with at least three M8 screws. The screws
must be tightened with a torque of 18 Nm.
3.3. Model plate
The model plate must be positioned so that it cannot be damaged
and must be clearly legible when the heater is installed (otherwise a
duplicate model plate must be used).
Inapplicable years must be erased from the model plate.
Fig. 1: Permitted installation positions for the Thermo 90 S /
Thermo 90 ST
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Examples for installation Thermo 90 S / Thermo 90 ST
40
4 Examples for installation
Fig. 2: Installation example for the Thermo 90 S / Thermo 90 ST heater
1 Heat exchanger, car’s heating system
2 Switch for car’s heating system fan
3 Relay for vehicle fan
4 Digital timer
5 Fuse strip in the car
6 Non-return valve with leakage hole
7 T-piece
8 Vehicle engine
9 Heater
10 Circulating pump
11 Water pump
12 Radiator
13 Regulating valve
14 Exhaust silencer
15 Metering pump
16 Combustion air intake line
17 Thermostat
18 Control module (optional on the Thermo 90 S)
19 Control module (installation position of the
Thermo 90 ST and optional for the Thermo 90 S)
Without non-return valve With non-return valve and thermostat
Wiring harness
Fuel line
Exhaust line
Water circuit
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 40 Friday, March 8, 2013 4:26 PM

Thermo 90 S / Thermo 90 ST Connection to the vehicle cooling system
41
5 Connection to the vehicle cooling system
In thermostat circuits, only use thermostats which start to open
at < 65 °C.
The heater is connected to the vehicle cooling system as shown in
Figure 2. The system must contain at least 6 litres of coolant.
The water hoses supplied by Webasto must always be used. If you do
not use these hoses, the hoses that you do use must comply with DIN
73411. The hoses must be installed without kinks and (to ensure perfect
bleeding) rising if possible. Hose connections must be supported by
hose clips to prevent them slipping.
NOTE:
The hose clips must be tightened with a torque of 4 Nm.
The cooling system must be bled carefully before using the heater for
the first time or after replacing the coolant. The heater and lines should
be installed in such a way as to ensure static bleeding.
Perfect ventilation can be identified by the circulating pump operating
almost silently.
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 41 Friday, March 8, 2013 4:26 PM

Fuel supply Thermo 90 S / Thermo 90 ST
42
6 Fuel supply
The fuel is taken from the vehicle fuel tank or from a separate fuel tank.
The values for the maximum pressure at the fuel extraction point are
shown in the table below.
Only for ADR: The statutory regulation of ADR (Accord européen relatif
au transport international des marchandises dangereuses par route)
governing fuel tanks, part 9 para. 9.2.4.7, must be adhered to.
NOTE:
A sign must be affixed to the fuel filler neck warning that the heater must
be switched off before refuelling.
Permissible fuel inflow
height H (m) At max. pressure (bar) in fuel line
0.00 0.2
1.00 0.11
2.00 0.03
Maximum fuel intake
height S (m) At max. negative pressure (bar) in the fuel tank
0.00 -0.10
0.50 -0.06
1.00 -0.02
Fig. 3: Fuel supply
l
1
+ l
2
≤10 m
l
1
≤1.2 m
l
2
≤8.8 m
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Thermo 90 S / Thermo 90 ST Fuel supply
43
6.1. Vehicles with diesel engines
The fuel must be taken from the vehicle fuel tank or from a separate tank
(see Figs. 4, 5 and 6).
NOTE:
Deburr the cut on the tank connector after sawing it off and remove any
metal chips.
NOTE on Fig. 6:
The fitting must be made from metal!
Fig. 4: Fuel pickup from the plastic tank
(Pickup via tank fitting)
Sealing ring
Fuel extractor
Tank fittings
Fig. 5: Fuel pickup from the plastic tank
(Pickup via tank drain screw)
Fig. 6: Webasto tank connector
Sealing ring
Plastic tank
Hole pattern
Only use a tank connector if the
fuel tank is made from metal
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 43 Friday, March 8, 2013 4:26 PM

Fuel supply Thermo 90 S / Thermo 90 ST
44
6.2. Vehicles with petrol engines
The heater must be integrated into the return line of fuel systems in
carburettor and injection engines with a return line.
In carburettor engines without a return line the heater must be integrated
into the fuel system in the supply line between the fuel tank and the
vehicle pump.
NOTE
A fuel feed line can normally be identified by the fact that a fuel filter is
installed in it.
NOTE:
If there is an evaporation tank in the vehicle’s fuel system, the fuel must
be extracted upstream of the evaporation tank.
Fuel may only be taken from the supply or return line using the special
Webasto fuel extractor (see Figure 7).
The fuel extractor must be fitted in such a way that any air or gas
bubbles are automatically discharged towards the tank (see Figure 7).
Air or gas bubbles may be produced in the vehicle’s fuel line if there are
leaks in the carburettor or vehicle fuel pump or if the ambient
temperature is higher than the evaporation temperature of the fuel.
The fuel extractor must not be located near the engine, as gas bubbles
may form in the lines on account of heat radiated from the engine. This
may cause problems during combustion.
When installing the heater in a vehicle with fuel injection system, it is im-
portant to establish whether the fuel pump is located inside or outside
the tank. If the fuel pump is located inside the tank, fuel can only be
extracted from the return line. In this case it must be ensured that the
return line continues almost to the bottom of the tank and is not sealed
by a non-return valve. If this is not the case the return line may be
extended.
If the fuel pump is installed outside the tank, the fuel connection may be
made between the tank and the fuel pump.
6.3. Fuel lines
Only steel, copper and plastic lines of plasticised, light and temperature-
stabilized PA 11 or PA 12 (e.g. Mecanyl RWTL) pursuant to DIN 73378
may be used for the fuel lines.
Fig. 7: Webasto fuel extractor
to metering pump
to engine
from tank
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Thermo 90 S / Thermo 90 ST Fuel supply
45
NOTE:
Cut Mecanyl lines without burr and do not crush them. Do not cut them
with side-cutting pliers.
Since the lines normallycannot be routedwith aconstant rising gradient,
the internal diameter must not be allowed to exceed a certain size. Air
or gas bubbles will accumulate in lines with an internal diameter of more
than 4 mm and these will cause malfunctions if the lines sag or
are routed downwards. The diameters specified in Figures 3 and 7 will
ensure that bubbles do not form.
The lines should not be routed downwards from the metering pump to
the heater.
Unsupported fuel lines must be secured to prevent them sagging. They
must be installed in such a way that they cannot be damaged by flying
chippings and high temperatures (exhaust line).
6.3.1. Connecting two pipes with a hose
The correct procedure for connecting fuel lines with hosing is illustrated
in Fig. 8.
NOTE:
Ensure that there are no leaks.
6.4. Metering pump with damper
The metering pump is a combined delivery, metering and shutoff system
and is subject to specific installation criteria (see Figs. 3, 9 and 10).
6.4.1. Installation location
Before installing the metering pump, ensure that the maximum pressure
occurring at the pickup point is less than 0.2 bar.
It is advisable to install the metering pump in a cool place. The maximum
ambient temperature must not exceed + 20 °C for pet rol and + 40 °C for
diesel at any time during operation.
The metering pump and fuel lines must not be installed within range of
the radiated heat from hot vehicle parts. A heat shield must be used if
necessary.
Fig. 8: Pipe / hose connection
Fig. 9: Metering pump DP2
Installation position and attachment
Clip
Bubble
Correct
Wrong
Bubble
12 V and 24 V – petrol and diesel
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Fuel supply Thermo 90 S / Thermo 90 ST
46
The pump should ideally be installed near the tank.
6.4.2. Installation and attachment
The metering pump must be secured with a vibration-damping
mounting. Its installation position is limited as shown in Figs. 9 and 10 in
order to ensure effective auto-bleeding.
6.5. Fuel filter
Only a Webasto filter, order no. 487 171, is allowed to be used if the fuel
is expected to be contaminated. Install vertically if possible, however at
least horizontally.
NOTE:
Note the installation position and direction of flow.
Fig. 10: Metering pump 30.2
Horizontal installation position
12 V and 24 V – diesel only
Fig. 11: Fuel filter
0°- 90°
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Thermo 90 S / Thermo 90 ST Combustion air supply
47
7 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 so that it cannot become
clogged with dirt or snow and cannot suck in splashing water.
The combustion air intake line (internal diameter at least 30 mm) may be
0.5 m to 5 m long with several bends totalling 360°. The minimum
bending radius is 45 mm.
The combustion air intake must not be routed above the exhaust outlet.
NOTE:
If the combustion air intake line cannot be installed so that it slopes
downwards, a water drain hole with a diameter of 4 mm is to be made at
its lowest point.
If the heater is installed in a general installation space near the vehicle’s
fuel tank, the combustion air must be taken in from the outside and the
exhaust fumes discharged into the atmosphere. The openings must be
splash-proof.
A ventilation opening measuring at least 6 cm
2
is required if the heater
is installed in an enclosed box. The size of the ventilation opening must
be increased accordingly if the temperature in the box exceeds the
permitted ambient temperature of the heater (see Technical data).
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 47 Friday, March 8, 2013 4:26 PM

Exhaust pipe Thermo 90 S / Thermo 90 ST
48
8 Exhaust pipe
The exhaust pipe (internal diameter 38 mm) can be installed with a
length of 0.5 m to 5 m and several bends (360°alto gether, minimum
bending radius 85 mm). The exhaust silencer 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 12).
The exhaust pipe opening must be located so that it cannot become
clogged with snow and mud.
Rigid pipes of unalloyed or alloyed steel with a minimum wall thickness
of 1.0 mm or flexible piping of alloyed steel only must be used as
exhaust line. The exhaust pipe is secured to the heater using a clamping
collar,for example. See the statutory regulations for other requirements.
Only for ADR: The statutory regulation of ADR (Accord européen relatif
au transport international des marchandises dangereuses par route)
governing the routing of the exhaust line, part 9 para. 9.2.4.7, must be
adhered to.
Fig. 12: Exhaust pipe opening
Installation position
An attachment is required no further than 150 mm from the end of the
exhaust pipe to ensure that the angle of 90° ±10°is achieved
Discharge direction almost vertical 90° ±10°
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Thermo 90 S / Thermo 90 ST Electrical connections
49
9 Electrical connections
9.1. Control module / heater connection
The electrical connection of the heaters is made as shown in the circuit
diagrams in Figures 15, 16, 17, 18, 19, 20, 21 and 22.
9.2. Connection when installing Thermo 90 S-ADR
and Thermo 90 ST-ADR in a hazchem vehicle (ADR)
To install the Thermo 90 S-ADR and Thermo 90 ST-ADR heaters in haz-
chem vehicles, the requirements of ADR/RID part 9 para. 9.2.4.7 –
Combustion heating systems, must also be satisfied. The electrical
connection is made as shown in the circuit diagram, Figs. 17, 18, 21
and 22.
NOTE:
The switch S7 must be installed in such a way that a positive potential
is connected to appropriate input of the control module when a pumping
device is switched on.
If there is no earth via Y2 or H5 at control module input X12/5
(Thermo 90 S) or X8/5 (Thermo 90 ST) when it is switched on, all the
ADR functions are disabled.
After activating the positive potential at control module input X12/5
(Thermo 90 S) or X8/5 (Thermo 90 ST) (auxiliary power take-off on) a
brief run-on time of 20 seconds on the Thermo 90 S (40 seconds on the
Thermo 90 ST) will takeplace,followingwhichthecontrolmodule willbe
in “Fault lock-out” mode.
IMPORTANT
In accordance with the technical specifications of the act governing the
road haulage of hazardous materials, heaters are only allowed to be
taken into service with a special manually operated switch fitted in the
cab.
If the system is equipped with a standard clock, ensure that contact 4 on
the standard clock remains free. The heater can then only be taken into
service using the immediate heat button (circuit diagram available on
request).
The use of other timers in ADR vehicles is not permitted.
9.3. Connecting the controls
The heater can be switched on and off using the following Webasto
controls:
– Timer, see circuit diagrams in Figures 15, 16, 19 or 20.
– Switch, see circuit diagrams in Figures 17, 18, 21 or 22.
9.4. Vehicle fan
The vehicle's own heater fan is controlled using a relay, see circuit
diagram Figs. 15, 16, 17, 18, 19, 20, 21, 22 or using a relay with a cabin
thermostat.
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Electrical connections Thermo 90 S / Thermo 90 ST
50
9.5. Thermo 90 S control module
The control module offers protection type IP6K4K if it is installed in the
position shown in Figure 13.
9.6. Thermo 90 ST control module
The control module offers protection type 6K9K if it is installed in the
position shown in Figure 14.
9.7. To set the regulating temperatures
Thermo 90 S / Thermo 90 ST
If the “Engine on”/”Engine off” signal (terminal D+) is applied to control
module plug X12 contact 7 (Thermo 90 S) or plug X8 contact 7
(Thermo 90 ST), different regulating thresholds take effect
If the terminal D+ signal is not applied, the temperatures are the same
as those at “Engine off”.
NOTE:
The selected regulating pause temperature of the heater should be
lower than the opening temperature of the radiator thermostat.
Fig. 13: Thermo 90 S (from 03/97) control module, installation position
Fig. 14: Thermo 90 ST control module, arbitrary installation position
Nominal
temperature at
the sensor
Regu-
lating
pause
Switch on again
after regulating
pause
“Engine on” 72 °C 82 °C 67 °C
“Engine off” 80 °C 90 °C 75 °C
1301494D_Installation_Instructions_Thermo_90_S_ST_DE_EN_FR.book Page 50 Friday, March 8, 2013 4:26 PM