Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
CH Demand
Access the X20 connector on the right hand side of the PCB
Disconnect the connector to the fan and make safe
Disconnect the connector to the fan and make safe
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance as necessary.
Measure the voltage between the wire 4th down from the top
on the RHS of the connector (may be grey or yellow
depending on age of harness) to a suitable earth point.
Approximately 20 seconds after the appliance is switched on the voltage should change from 0V DC to approx. 22V DC.
Measure the voltage between the wire 4th down from the top
on the RHS of the connector (may be grey or yellow
depending on age of harness) to a suitable earth point.
Approximately 20 seconds after the appliance is switched on the voltage should change from 0V DC to approx. 22V DC.

Isolate as per TOPs P4
and refit as necessary