Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
DHW Demand
Gain access to PCB (use Insulation Mat as required)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Press reset to cancel purge cycle countdown.
Test 1.
Measure the voltage across connections 2 (red) and 3 (black).
Expected voltage approximately 27 Volts DC.
Test 2.
Measure the voltage across connections 3 (black) and 6 (orange).
Expected voltage 4-13 Volts DC.
Test 1.
Measure the voltage across connections 2 (red) and 3 (black).
Expected voltage approximately 27 Volts DC.
Test 2.
Measure the voltage across connections 3 (black) and 6 (orange).
Expected voltage 4-13 Volts DC.
Isolate as per TOPs P4
and refit as necessary