BoilerFaultCodesWhat the manual says
Manufacturer manualDHWmode:Fanoverrun
What causes this fault?
This scenario occurs when the boiler's internal computer keeps the fan spinning after the burner has turned off to clear away residual heat and combustion gases. While it is often just a normal part of the cooling process, it can also happen if the system detects that temperatures inside the unit are staying high for longer than they should. In rare cases, it may indicate that the control board is misreading signals from the fan.
This status is more noticeable during summer when the boiler is only used for hot water, as the lack of central heating circulation makes the cooling process more distinct.
DIY fix possible
No action required; this is a status code, not a faultAllow the boiler to complete its cooling cycleMonitor only if the fan runs indefinitely without the boiler firing
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
Affiliate links. We may earn a commission at no extra cost to you.