Medium
S.53 on Glow-worm Easicom 24

Your boiler has temporarily slowed down because the water returning to the system is much cooler than the water leaving it, indicating a potential restriction in your radiators or pipes.

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.

What the manual says

Manufacturer manual

Waiting cycle: temperature differential between heating flow and return is too high. If ∆T > 30, forcing to Pmin.

From this model's manual
Verified against the Glow Worm Easicom 24 installation & service manual, page 25.
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 that all radiator valves throughout your home are fully openEnsure your heating system has the correct pressure (usually between 1 and 1.5 bar)Bleed any trapped air from your radiators using a radiator key

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