Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Gain access to PCB (use Insulation Mat as required)
Place PCB in test position, click HERE for guidance
Remove the flame sense lead from terminal X501
Place PCB in test position, click HERE for guidance
Remove the flame sense lead from terminal X501
Gas On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure the voltage across terminals at X501 and X500 on the PCB
Expect approx. 70 V AC.
Note:
This voltage should be present regardless of which stage the boiler is in.
Expect approx. 70 V AC.
Note:
This voltage should be present regardless of which stage the boiler is in.
Isolate as per TOPs P4
and refit as necessary