Set Appliance State:
Mains Power Off
Set Multimeter to DC Volts 
Turn Hot Water Tap On
CH temperature selector to 0 position
DHW temperature selector to 0 position
DHW temperature selector to 0 position
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Reset lockout as necessary.
Test 1.
DHW temperature selector to maximum position. Allow fan to run.
Measure voltage across the connections on gas valve 1 (grey leads,
solenoid farthest to the right). Expected voltage approximately 26 volts DC.
DHW temperature selector to 0 position.
Test 2.
Reset lockout as necessary.
DHW temperature selector to maximum position.
Allow fan to run.
Measure voltage across the connections on gas valve 2 (grey leads, middle solenoid). Expected voltage approximately 26 volts DC
Note: Voltage will only be present for approximately 5 seconds after the fan has started to run and appliance will go to lockout as burner will not ignite.
Test 1.
DHW temperature selector to maximum position. Allow fan to run.
Measure voltage across the connections on gas valve 1 (grey leads,
solenoid farthest to the right). Expected voltage approximately 26 volts DC.
DHW temperature selector to 0 position.
Test 2.
Reset lockout as necessary.
DHW temperature selector to maximum position.
Allow fan to run.
Measure voltage across the connections on gas valve 2 (grey leads, middle solenoid). Expected voltage approximately 26 volts DC
Note: Voltage will only be present for approximately 5 seconds after the fan has started to run and appliance will go to lockout as burner will not ignite.
Isolate as per TOPs P4
and refit as necessary