5
Fault Finding
21
Blue Seal Evolution Series Gas Convection Ranges
© Copyright Moffat Ltd. 21 June 2016
Amendment 13
Door microswitch out of adjustment / faulty
With the pilot lit and thermostat ‘On’, open the oven door and
manually depress the door microswitch actuator rod at the top
right of the oven. If this activates the oven burner, the
microswitch requires adjustment.
Check the voltage to microswitch Terminal ‘com’. If there is no
voltage then check the wiring. If there is voltage, check
Terminal N.C.
With the door closed (ie microswitch actuated), there should be
power to Terminal N.C. If no power at Terminal N.C, the
microswitch is faulty - replace the door microswitch.
Thermostat faulty
Close oven door and set thermostat to 200°C. Check voltage to
Terminal 2 on thermostat. If there is no voltage, check the
wiring.
Check voltage out of Terminal 1 on thermostat. If there is no
voltage, thermostat is faulty - replace the thermostat.
Solenoid valve faulty
Check voltage to solenoid coil on the gas valve. If there is no
voltage, check wiring.
If power to solenoid is correct and valve will not pass gas, coil is
faulty - replace solenoid valve.
Thermostat out of calibration
Place an accurate digital thermometer probe or thermocouple in
the centre of oven. Set thermostat to 180°C.
Close oven door and allow oven thermostat to cycle ‘On’ and
‘Off’ twice. Record oven centre temperature for the next
thermostat ‘On’ and ‘Off’ cycle.
The thermostat should cycle between 165°C and 195°C when
set to the above temperature.
If oven temperature is outside these ranges, the thermostat
requires recalibration.
Fan motor capacitor faulty
Ensure that oven is isolated from power supply. Disconnect all
wires from capacitor.
Briefly short across the capacitor terminals to ensure that it is
fully discharged.
Using a multimeter, measure resistance across capacitor
terminals.
Resistance should start low and quickly increase to infinity
within 5-10 seconds.
If resistance does not increase at all, capacitor has shorted -
replace the capacitor.
If capacitor is infinite resistance straight away then it is
open-circuit - replace the capacitor.
If resistance never goes very high, the capacitor is leaky -
replace the capacitor.
5.2.3 Oven Main Burner will not light
5.2.4 Fan does not operate
5.2.5 Oven too hot or too cold
Summary of Contents for Evolution Series
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