Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Turn Hot Water Tap On
Selector Switch to Hot Water and Heating
Gas On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance as necessary.
Using shrouded probes measure the voltage across
terminals at X501 and X500 on the PCB
Expect approx. 70vAC before the flame is present
Then when the flame lights the voltage should drop to approx. 59vAC or lower.
Using shrouded probes measure the voltage across
terminals at X501 and X500 on the PCB
Expect approx. 70vAC before the flame is present
Then when the flame lights the voltage should drop to approx. 59vAC or lower.
Isolate as per TOPs P4
and refit as necessary