Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Gain access to PCB (use Insulation Mat as required)
Remove connector CN10 from the PCB and make safe
Ensure no demands
Remove connector CN10 from the PCB and make safe
Ensure no demands
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Cancel purge cycle & If required, reset boiler. (see note 1.)
Test 1.
Measure for DC voltage across pin 4 CN10 on PCB & a suitable earth connection.
Expected voltage approximately 28 Vdc, if voltage is not as expected choose that option from below.
Test 2.
Turn hot water tap On, measure for DC voltage across pin 3 CN10 PCB and
a suitable earth connection. (see note 2.)
Expected voltage approximately 15 - 19 Vdc, if voltage is not as expected choose that option from below
Note.
1. Fan will be running during test due to signal control connector being disconnected.
2. Boiler may enter lockout during test, reset boiler as required until test complete
Test 1.
Measure for DC voltage across pin 4 CN10 on PCB & a suitable earth connection.
Expected voltage approximately 28 Vdc, if voltage is not as expected choose that option from below.
Test 2.
Turn hot water tap On, measure for DC voltage across pin 3 CN10 PCB and
a suitable earth connection. (see note 2.)
Expected voltage approximately 15 - 19 Vdc, if voltage is not as expected choose that option from below
Note.
1. Fan will be running during test due to signal control connector being disconnected.
2. Boiler may enter lockout during test, reset boiler as required until test complete
