Set Appliance State:

Mains Power Off
DHW temperature selector to 0 position
CH temperature selector to 0 position
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Fully depress the reset switch on the appliance and hold for 1 second then release, a click should be heard as the switch is operated.
Does the fan run for approximately 5 seconds and then stop and the appliance stay in standby mode?