Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
CH Demand
CH temperature control to maximum
DHW temperature control to minimum
CH temperature control to maximum
DHW temperature control to minimum
Remove control box cover
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Test 1:
With external controls turned OFF measure the voltage across the terminals of M5 marked 'Timer' on the PCB.
Expect 16 Vdc.
Test 2:
With external controls turned ON measure the voltage across the terminals of M5 marked 'Timer' on the PCB.
Expect 0 Vdc.
With external controls turned OFF measure the voltage across the terminals of M5 marked 'Timer' on the PCB.
Expect 16 Vdc.
Test 2:
With external controls turned ON measure the voltage across the terminals of M5 marked 'Timer' on the PCB.
Expect 0 Vdc.
