Set Appliance State:

NO Demands
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Confirm the boilers maximum heating power is set correctly for the CH system the boiler is attached to by entering the diagnostic codes, and reviewing parameter "d.00", this is the maximum KW output for central heating from the appliance.
If the maximum heating output from the appliance is set too low for the size of the installation this will prevent the boiler and system reaching the set temperature.
Click here for how to enter and adjust diagnostic codes.