Valeo spheros thermo 230, Workshop Manual

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Thermo 230 / 231 / 300 / 301 / 350 6 Functional Checkouts
– screw on the test gauge with bleeding feature.
– Follow the instructions in the menu component test of
the PC heater diagnosis.
– Open the bleed port at the pressure test gauge until
some fuel escapes, collect it e.g. with a cloth. Close
the bleed port and read the present pressure at the
gauge.
– after approximately 13 sec. pump pressure is
indicated (refer to the diagram above).
– If the specified pressure cannot be reached, it can be
readjusted. For that rotate the adjusting screw max.
one revolution. If the prescribed pressure despite
readjustment not be achieved or occur leaks, the fuel
pump must be replaced.
– screw in nozzle and torque with 20 Nm.
ATTENTION:
Do not tuch or damage nozzle bore.
6.3.6 Fan Motor Check
NOTE:
The fan motor check is performed with the burner
installed. If normal conditions are not obtained the fan
motor must be replaced.
Check
– check fan motor bearing condition(binding)
– measure heater power supply voltage
– switch on heater
– measure speed and compare with the diagram below
Thermo 230/231 4400 ±350 24 Volt
Thermo 300/301 5200 ±420 24 Volt
Thermo 230 6200 ±500 24 Volt
6.3.7 Solenoid Valve Check
NOTE:
A solenoid valve leaking valve seat shows by rather long
smoke emissions during run-down. In this case fuel keeps
dripping through the fuel nozzle.
Short smoke emissions are normal caused by clearing the
area between solenoid valve and nozzle bore.
Check
ATTENTION:
Disconnect solenoid valve connector from control
unit to avoid damage to the control unit.
– Check electrics for the following values:
• break voltage 17.0 Volts
• operating voltage 19.2 ... 28.8 Volts
• power consumption at
nominal voltage and 20 °C
10 Watts
• nominal current 0.42 Amps
NOTE:
On heaters with control unit 1572 the solenoid valve may
also be checked by means of the PC heater diagnosis
(component test).
6.3.8 Nozzle Block Preheater Check
NOTE:
At a temperature of < 0 °C the heater cartridge in the
nozzle block is activated. The heating period depends on
the heat reflected within the combustion chamber.
Preheating is deactivated when the thermostat ambient
temperature is +8 °C.
Power consumption is 130 ±13 Watts at 24 Volt.
Check
– swing burner head open or remove
– disconnect electrical connector from nozzle
– connect ohmmeter to connector
– using cooling spray cool down thermostat or bridge
– resistance (max. 4.5
Ω
).
20 22 24 26 28 30 32
2500
18
3000
3500
4000
4500
5000
5500
6000
6500
7000
7500
8000
Thermo 350
Thermo 300
Thermo 230
Voltage
Spee
d (1
/min.)