Set Appliance State:

Selector switch to DHW & CH with NO preheat
Ensure NO demands and that the boiler is cool
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Allow the boiler to complete its start-up sequence as illustrated.
Once completed the current system temperature should be displayed and neither of the LED's should be lit, the appliance should remain in standby with the pump and fan NOT running.
If the appliance enters an air purge cycle (as illustrated) click here.
Flashing numbers in the display indicate a fault code.
Notes:
1. If the red light is illuminated the appliance must be reset, faults where the red LED is not lit will auto reset once the fault is rectified.
2.To reset the boiler turn the selector switch to the OFF position and then back to the DHW & CH with NO preheat position.