Set Appliance State:
Mains Power Off
Set Multimeter to DC Volts 
CH Demand
Operating Switch in Heating & Water position
Gas On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure the DC voltage across Yellow connections on connector X2 (Modureg).
The voltage should gradually increase over a period of approximately one minute.
At minimum the voltage will be approximately 10vdc or less
Note:
The system MUST be in a cold state for this to happen.
The voltage should gradually increase over a period of approximately one minute.
At minimum the voltage will be approximately 10vdc or less
Note:
The system MUST be in a cold state for this to happen.
Isolate as per TOPs P4
and refit as necessary