Valeo spheros thermo 230, Workshop Manual

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Thermo 230 / 231 / 300 / 301 / 350 2 General Description
2.8 Temperature Sensor
The temperature sensor senses the coolant temperature
at the heat exchanger outlet as an electrical resistance.
This signal is supplied to the control unit for processing.
2.9 Temperature Limiter
The temperature limiter (bimetal) protects the heater
against undue high operating temperatures.
The temperature limiter can be reset manually.
The temperature limiter responds at a temperature in
excess of 125°C to switch off the heater.
In the case of Thermo 231 and 301 as well as the Rail
variant .126, the temperature limiter will trip at a
temperature in excess of 105°C.
After the temperature has dropped, an automatic reset will
occur.
2.10 Overheat Thermostat for burner
(Thermo 231 and 301 only)
The overheat thermostat is screwed onto the disk and
electrically connected to the solenoid valve of the fuel
pump. When the burner overheats the thermostat causes
an error lockout.
2.11 Circulation Pump
The externally mounted circulation pump ensures proper
coolant circulation in the vehicle and heater circuit.
Depending on the application, the circulating pump is
switched on via the control unit or directly via the vehicle
electrical system and operated during the entire heater
operation duration.
The heaters can be operated with the circulation pumps
Aquavent 5000 (U4814), Aquavent 5000S (U4854),
Aquavent 6000C (U4855) or Aquavent 6000SC (U4856).
The circulating pump fuse may never be pulled, while the
pump is running, and may not be replaced, when the
pump is switched on.
Igniter electrodes
Igniter Box
Temperature sensor
Temperature
limiter
Circu
latin
g pu
mp
Delivery rat
e
Rat
ed vo
ltag
e
Operatin
g vo
ltag
e rang
e
Rat
ed p
o
w
er con
sum
ptio
n
Weig
ht
l/h V = V = W kg
U 4814
Aquavent
5000
5000
(against 0,2 bar)
12
or
24
10…14
or
20…28
104 2,1
U 4854
Aquavent
5000S
5000
(against 0,2 bar)
24 20…28 104 2,2
U 4855
Aquavent
6000C
6000
(against 0,4 bar)
24 20…28 210 2,4
U 4856
Aquavent
6000SC
6000
(against 0,4 bar)
24 20…28 210 2,5
Overheat Thermostat