Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
CH Demand
Remove DC electrical connector from fan assembly and make safe
Pull connector X5 back slightly to expose test points
Pull connector X5 back slightly to expose test points
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset boiler if required.
Measure the DC volts at the PCB connector X5
from each wire listed in the table to the
black wire (pin 4) on the PCB X5 connector.
Voltages should be approx. as follows:
Notes:
1. Wires may be multicoloured.
2. Test must be carried out during initial fan purge period
(within 4 minutes of power on) repeat as necessary.
Measure the DC volts at the PCB connector X5
from each wire listed in the table to the
black wire (pin 4) on the PCB X5 connector.
Voltages should be approx. as follows:
Notes:
1. Wires may be multicoloured.
2. Test must be carried out during initial fan purge period
(within 4 minutes of power on) repeat as necessary.
Isolate as per TOPs P4
and refit as necessary