Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Selector Switch in Hot Water Position
Hot Water Tap OFF
Gain access to PCB (use insulation mat as necessary)
Hot Water Tap OFF
Gain access to PCB (use insulation mat as necessary)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance as necessary.
Test 1: Measure the voltage between the two violet wires
marked 8 and 9 on connector X4 at the PCB.
Voltage should be approximately 28V DC.
Test 2: Turn hot water tap ON.
Continue to measure the voltage between the two violet
wires marked 8 and 9 on connector X4 at the PCB.
Within 4 seconds after the pump begins to run the
voltage should drop to approximately 0V DC.
Test 1: Measure the voltage between the two violet wires
marked 8 and 9 on connector X4 at the PCB.
Voltage should be approximately 28V DC.
Test 2: Turn hot water tap ON.
Continue to measure the voltage between the two violet
wires marked 8 and 9 on connector X4 at the PCB.
Within 4 seconds after the pump begins to run the
voltage should drop to approximately 0V DC.
