Medium
F.023 on Vaillant ecoTEC Plus 832

Your boiler is struggling because there is air trapped inside the system, which is preventing hot water from circulating 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

Air in the product. The temperature spread between the flow/return is too great.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 81.
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's pressure gauge and ensure it is between 1 and 1.5 barBleed all the radiators in your home starting from the lowest floor and working upwardsTop up the system pressure again if it drops after bleeding the radiatorsRestart the boiler using the reset button or power switch

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