Set Appliance State:

Mains Power Off
Ensure there is no demand for either CH or DHW
Preheat OFF
Selector switch to Hot Water position
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

When power is switched on the boiler should run a self-check as follows:
1. The fan starts to run and the display will illuminate showing 24/30/35kW Combi for 10 seconds.
2. Display shows "Pump Overrun" for 20 seconds (during this period the pump will run).
3. Display Shows "Fan Post-Purge" for 4 minutes (during this time the fan will run).
When self-check has completed the display should show "For central heating turn mode knob clockwise" scrolling with "Summer Mode" on a continuous loop indicating the boiler is in standby and awaiting a request for heat.
If the display does not progress from the "24/30/35kW Combi" CLICK HERE.