Set Appliance State:

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

Observation:

Set boiler control switch to L position.
Allow the boiler to ignite and reach temperature.
Remove CH demand.
Wait until the boiler returns to standby.
Set boiler control switch to L position.
Does the display should now show 't' and have a re-ignite delay time of approximately 5 minutes?