BoilerFaultCodesTechnical description
Check pump for shorts between L/N and L/E. Disconnect pump and lead to PCB 41, renew fuse and reconnect to determine faulty item.
What causes this fault?
This fault occurs when an electrical component within the boiler draws too much current, causing a safety fuse on the control board to blow and cut all power. The most common reason is that the central heating pump has developed an internal short circuit or has seized, often due to a build-up of debris or water leaking into its electrical housing.
This issue is most frequent at the start of autumn when the heating is turned on for the first time after summer, as the pump is prone to seizing after long periods of inactivity.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.