Set Appliance State:
Set Multimeter to Resistance 
Isolate Mains Power to appliance as per TOPs P4
Selector switch to Heating & Water
Room thermostat (if fitted) calling
Gain access to PCB
Selector switch to Heating & Water
Room thermostat (if fitted) calling
Gain access to PCB
Measurement:
Measure resistance between the top two connections, marked 'room stat', on connector X4 on the main driver board.
Note:
If no external controls are fitted a link must be present, with certain room thermostats (i.e. where power is required for switching) a temporary link may need to be fitted to simulate switching of thermostat.
Note:
If no external controls are fitted a link must be present, with certain room thermostats (i.e. where power is required for switching) a temporary link may need to be fitted to simulate switching of thermostat.
