Set Appliance State:

WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Press the power key, it may take 2 presses as the first key press
may illuminate the display only.
Does the display revert back to show the flow temperature (boiler turned On) ?
Note:
If a FAULT CODE appears during or after this test, then CLICK HERE