Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Turn Hot Water Tap On Fully
Remove plastic top cover from Gas Valve.
(Held by one screw in the top R/H corner of the cover)
ON/OFF Switch in ON Position
CH Temp Selector in Minimum position
DHW Temp Selector in Maximum position
Mode Selector Switch in Heat and Hot water position
Remove plastic top cover from Gas Valve.
(Held by one screw in the top R/H corner of the cover)
ON/OFF Switch in ON Position
CH Temp Selector in Minimum position
DHW Temp Selector in Maximum position
Mode Selector Switch in Heat and Hot water position
Gas On
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow Fan to run and burner to ignite.
Measure Voltage across the connections of the Modulating Solenoid.
At full rate the expected Voltage is approximately 18 Volts DC.
Measure Voltage across the connections of the Modulating Solenoid.
At full rate the expected Voltage is approximately 18 Volts DC.
Isolate as per TOPs P4
and refit as necessary