BoilerFaultCodesYour boiler is simply running an automatic air-removal cycle after being switched off or experiencing a brief power cut.
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: Venting program active when power turned on / interrupted (runs for 7 mins)
What causes this fault?
This occurs when the boiler detects that power has been disconnected and restored, triggering a safety routine to protect the internal components. The system enters this mode to automatically purge any trapped air bubbles from the heat exchanger and pipework that may have shifted while the pump was off. It is a standard startup procedure rather than a mechanical failure.
This can be more frequent during winter months when local power grids are under higher strain or during stormy weather that causes brief electrical flickers.
DIY fix possible
Wait for 7 minutes for the automated cycle to completeEnsure your radiators are turned up high during this periodCheck that your boiler pressure is between 1.0 and 1.5 bar
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A boiler cover plan would cover faults like 105 — no call-out fees, no surprises.
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