BoilerFaultCodesYour boiler is still working but cannot reach its full power, meaning your radiators might not get as hot as they should.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Reduced burner output
What causes this fault?
This fault occurs when the boiler's control system detects that the burner cannot maintain its regular intensity, forcing it to operate at a lower power level. The most common reason is that the boiler is struggling to accurately monitor or control the gas flow and flame strength required for full heat. While the boiler stays on, it cannot generate enough energy to satisfy high demands for heating or hot water.
This issue is often more noticeable during winter when the boiler is expected to work at maximum capacity to heat a cold home.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 47 — no call-out fees, no surprises.
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