BoilerFaultCodesWhat the manual says
Manufacturer manualPower supply has been interrupted. This fault code may appear on first commissioning the boiler, or if the power is interrupted while the boiler is in operation.
What causes this fault?
This fault occurs when the boiler’s electronic brain suddenly loses its electrical connection, causing the unit to shut down instantly for safety. It is usually triggered by a blown internal fuse or a failure within the main circuit board that prevents power from flowing through the system. In some cases, an external issue like a tripped circuit breaker or a loose wire in the wall switch can also be the root cause.
This fault is slightly more common during stormy weather or winter months when power surges and local grid instability are more frequent.
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.
Avoid the next call-out bill
A cover plan would handle faults like 04: no call-out fees, no surprise bills.
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