Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4

Observation:

Check the DHW control thermostat for correct setting fitting and operation.
i.e.
Temperature is approximately 55°C or as customer requirements.
Thermostat is positioned correctly approximately 1/3 of the way up the HSV (hot storage vessel/cylinder/tank) and thermostat is in contact with the HSV.
Thermostat does actually switch.