Medium
S.53 on Vaillant ecoTEC Pro 30

Your boiler is temporarily pausing its operation to protect itself because the water is not moving through the system quickly enough.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

Product is within the waiting period of the modulation block/operation block function as a result of low water pressure (flow/return spread too large)

DIY fix possible

Check all your radiator valves are fully openEnsure your system pressure is at the correct level (usually between 1 and 1.5 bar on the gauge)Bleed all radiators to release any trapped air and then top up the pressure again

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F.22View →S.54View →

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