Set Appliance State:

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

Observation:

The fan should run at ignition speed about
20sec after the pump starts.
Check the fan speed by:
Entering the On Board Diagnostics and scroll to d34 using the +/- buttons.
The actual fan speed will be displayed at the top of the screen.
Expect approx. values of 340 LOW rising to 500 HIGH as the fan speed reaches a maximum.