BoilerFaultCodesWhat the manual says
Manufacturer manualFlow sensors check signal, pump or system
What causes this fault?
This fault occurs when the electrical circuit feeding the boiler is interrupted, meaning the control system has no power to operate. The most common reasons are a blown fuse in the external wall switch, a tripped circuit breaker in your fuse box, or a failure of the internal components that manage electricity within the boiler itself.
This fault is more common during the winter months when heavy electrical demand or local power surges can cause external fuses or circuit breakers to trip.
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 79: no call-out fees, no surprise bills.
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