Set Appliance State:

Mains Power Off
Ensure NO demands
Boiler DHW thermostat set to MAX
Boiler CH thermostat set to MAX
Selector switch to Winter mode
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

With no demand the boiler should enter standby, this is indicated by the pump and fan not running.
Does the boiler enter standby correctly?