Set Appliance State:
Set Multimeter to DC Volts 
Turn Hot Water Tap On
Isolate Mains Power to appliance as per TOPs P4
Selector Switch in DHW position
DHW Temperature Control to Maximum
Selector Switch in DHW position
DHW Temperature Control to Maximum
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow fan to run and boiler to commence its ignition sequence.
Test 1: Check voltage across the grey solenoid connections
Test 2: Check voltage across the blue solenoid connections
Approximately 24 volts DC should be present at both tests
Note:
Voltage will only be present for approximately 8 seconds during ignition sequence after which time lockout will occur.
Boiler may have to be reset between tests.
Test 1: Check voltage across the grey solenoid connections
Test 2: Check voltage across the blue solenoid connections
Approximately 24 volts DC should be present at both tests
Note:
Voltage will only be present for approximately 8 seconds during ignition sequence after which time lockout will occur.
Boiler may have to be reset between tests.
Isolate as per TOPs P4
and refit as necessary