Medium
S.53 on Glow-worm Energy 35 Store

Your boiler is temporarily slowing down because the water inside is getting too hot too quickly, usually caused by blocked water flow.

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

Wait cycle: Temperature difference between heating flow and return is too high. If Δt > 30, then forced operation with Pmin.

From this model's manual
Verified against the Glow Worm/Glow Worm Energy 35 Store Installation And Maintenance Instruc installation & service manual.
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 your radiators are turned on and the valves are not completely closedEnsure your system pressure is at the correct level (usually around 1 to 1.5 bar)Restart your boiler using the reset button to see if normal operation resumes

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Related fault codes

F.22View →F.75View →S.30View →

All 72 fault codes on the Energy 35 Store

Seeing a different code? Every code this model can display, in one place.

F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.26F.27F.28F.29F.32F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.77F.79F.81F.83F.84F.85F.86F22S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.54S.96S.98S.99

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