Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Gain access to PCB (use Insulation Mat as required)
Disconnect the plug at the diverter valve
DHW temperature control to MIN
CH temperature control to MIN
On / Off switch set to OFF
Attach black probe to a suitable earth with a crocodile clip
Disconnect the plug at the diverter valve
DHW temperature control to MIN
CH temperature control to MIN
On / Off switch set to OFF
Attach black probe to a suitable earth with a crocodile clip
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
As voltage will only be measured briefly when power is turned on place
the red probe on the test pin for the pink wire on X4 connector at the PCB.
On / Off switch set to ON.
Voltage should fluctuate between 5V and 13V AC for
approximately 3 seconds before settling to 0V.
On / Off switch set to OFF.
Repeat the test for each of the other 3 wires on X4.
The measured voltage should be as above on each test.
the red probe on the test pin for the pink wire on X4 connector at the PCB.
On / Off switch set to ON.
Voltage should fluctuate between 5V and 13V AC for
approximately 3 seconds before settling to 0V.
On / Off switch set to OFF.
Repeat the test for each of the other 3 wires on X4.
The measured voltage should be as above on each test.
Isolate as per TOPs P4
and refit as necessary