Medium
S.53 on Vaillant ecoTEC Plus 610

Your boiler has temporarily stopped because it cannot circulate water efficiently, likely due to low pressure or an airlock in your heating system.

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

Productinwaitingperiod/operationblockfunctionduetolowwaterpressure(flow/returnspreadtoolarge)

From this model's manual
Verified against the Vaillant Ecotec Plus 610 installation & service manual, page 32.
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 the pressure gauge on the front of the boiler; if it is below 1.0 bar, use the filling loop to increase it to between 1.0 and 1.5 barBleed all radiators in the house starting from the ground floor and working upwards to remove trapped airCheck that all radiator valves and system isolation valves are fully open

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F.22View →S.51View →S.54View →

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