BoilerFaultCodesYour boiler is briefly cooling itself down after providing hot water and will resume normal operation in a few moments.
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: DHWmode:Pump/fanoverrun
What causes this fault?
This status occurs because your boiler needs to dissipate excess heat after you finish using hot water. The pump and fan continue to run for a short period to move heat away from the internal components and prevent any damage from overheating. Once the internal temperature has dropped to a safe level, the boiler will automatically return to its normal standby mode.
DIY fix possible
Wait 5-10 minutes for the boiler to complete its cooling cycleCheck that your radiator valves are open to allow heat to dissipateEnsure your system pressure is between 1.0 and 1.5 bar
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A boiler cover plan would cover faults like S.25 — no call-out fees, no surprises.
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