Low
222-F on Viessmann Vitopend 100

Your boiler has detected trapped air inside the system and is currently trying to clear it out to prevent the burner from overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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

Burner blocked. The venting program automatically starting

DIY fix possible

Wait for the boiler to complete its automatic 20-minute venting cycleCheck that your radiator valves are openCheck the boiler pressure gauge and top it up to 1.5 bar if it is too low

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