BoilerFaultCodesYour boiler is switching itself off because it is struggling to reach the correct temperature while trying to heat your hot water tank.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: OFF during DHW loading to set value 1
What causes this fault?
This fault occurs when the boiler is unable to transfer heat to your hot water tank quickly enough, causing the internal water temperature to climb too high and trigger a safety shutdown. The most common reasons are a faulty sensor giving the boiler incorrect readings or a mechanical failure in the valve that directs hot water to your cylinder.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 71:1 — no call-out fees, no surprises.
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