Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Unplug 4 pin connector at X12 from the PCB
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Observation:
With the programmer / selector switch disconnected does the demand light still illuminate?
Isolate as per TOPs P4
and refit as necessary