B

▶ Check the gas supply to the property and the inlet on the gas valve (check drop on inlet) and replace if required.
▶ Check the flame sense probe and the earth to the heat exchanger.
▶ Check the voltage to the gas valve and the continuity of harness and replace if required.
▶ Check the condition of the bearing plate.
▶ Check the flame sense plug is connected and the continuity of harness and replace if required.
▶ Check the condensate trap and the discharge route.
▶ Check the flue integrity test.