Medium
61 on Alpha Intec 50CS

Your boiler is struggling because air bubbles are trapped inside the system, preventing the water from circulating properly to heat your home.

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 pump - Restricted CH flow due to air or a circuit restriction

From this model's manual
Verified against the Alpha Intec 50cs installation & service manual, page 48.
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 and ensure it is between 1.0 and 1.5 barBleed all radiators in your home starting from the lowest floor to the highestTop up the system pressure again to 1.5 bar if it dropped while bleedingRestart the boiler to see if the error clears

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