Medium
4254 on Vokera Maxin

Your boiler has detected that air is trapped inside the system, which is preventing it from circulating heat effectively.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Auto Air Vent

From this model's manual
Verified against the Vokera Vokera Maxin installation & service manual, page 51.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check your boiler pressure gauge to ensure it is between 1 and 1.5 barBleed all radiators in your home starting from the lowest floor to the highestTop up the system pressure again using the filling loop if it dropped while bleedingRestart the boiler to clear the fault

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