Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to DC Volts Set meter to measure DC Volts
Remove DC electrical connector from fan assembly (5 pin connector) and make safe
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:

Reset boiler if required.
Measure the DC volts at the PCB connector X8 from
each wire listed in the table to the black wire (pin 3)
Voltages should be approx. as follows:
Lead
DC Volts
Yellow (pin 4)
4.9v
Pink (pin 5)
2.8v

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.