BoilerFaultCodesWhat the manual says
Manufacturer manualFan unit waiting period
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan isn't spinning at the correct speed required to safely clear exhaust gases before ignition. The most common reasons are a buildup of dust or debris within the fan assembly, or a communication error between the fan and the main control board. If the fan cannot reach its target speed, the boiler will temporarily pause as a safety precaution.
This issue can occasionally surface during very windy weather, as extreme gusts can create back-pressure in the flue that interferes with the fan's startup speed.
Engineer required
This fault requires 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 S.37: no call-out fees, no surprise bills.
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