BoilerFaultCodesTechnical description
Check the mains supply.
What causes this fault?
This fault occurs when the boiler's control system detects a total loss of incoming electrical power. The most common reason is a blown fuse on the circuit board or a tripped switch at the main fuse box, though it can also be caused by a faulty wall switch or a failure in the boiler's internal wiring.
This fault is occasionally more frequent during the winter months when power surges or local grid instability are more likely due to heavy electrical demand and adverse weather.
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.
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