Saunier Duval Themaclassic F30E Instructions For Use Installation And Servicing page 32

COMPONENT
Gas control valve
Resistance of coil 116Ω
Adjustment valve
( step motor)
(F30E Only)
Three way valve.
Electrical supply to motor
0Ω between 1 and 3.
9.6kΩ between 1 and 2.
9.6kΩ between 1 and 3.
(1, 2 and 3 marked on
the motor).
Thrust action of the motor.
(F30E Only)
Domestic water flow
4000122704-1
18 Fault Finding
NORMAL MEASURE
Under demand during ignition sparks:
24V dc for 1 to 2 seconds, then
12Vdc (constant) at the gas control
valve electrical connection.
Close the gas inlet:
Dismantle the step motor (screw not
sealed in). Trigger a demand and check
that the valve opens during the ignition.
When heating is on:
230V ac between 1 and 2 of the motor.
About 25V ac between 2 and 3.
When hot water is on:
230V ac between 2 and 3 of the motor.
About 25V ac between 1 and 2.
Unfasten the clip (OK, no risk of water
leak), pull out the motor and leave it
plugged in.
When hot water is on: the axle should
pull in. When heating is on : the axle
should push out.
32
CHECK
If 0 Volt: the gas control valve
is not faulty.
If 24 Volts and then 12 Volts
but no gas at the burner:
Check if the gas control valve is
stuck. If not, check the
adjustment valve.
If the valve does not move:
Check the connections at both
motor and control board (PCB).
Change the motor. Replace the
control board (PCB).
If voltages are different:
Connections.
Control board (PCB).
If electrical supply is OK.
but the motor axle does not move
Replace the motor, or replace
the control board (PCB).
To test: Use a new detector and
connect it electrically in place of
the faulty one . Blow through to
stimulate a demand for water.
Overheat thermostat reset button
Refer to Section 20.10 to locate the overheat thermostat
reset button.
Depress the button to reset.
OVERHEAT
THERMOSTAT
RESET
BUTTON
Diagram 18.1