Medium
S.53 on Glow-worm Easicom3 System

Your boiler has temporarily stopped working because it has detected an issue with the water flow or pressure within your heating system.

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

Productinwaitingperiod/operationblockfunctionduetolowwaterpressure(flow/returnspreadtoolarge)

From this model's manual
Verified against the Glow Worm Easicom3 System installation & service manual, page 42.
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's pressure gauge on the front display; if it is below 1.0 bar, you likely need to top up the pressure.Locate the external filling loop (a silver flexi-hose under the boiler) and slowly open the valves to let water in until the needle reaches 1.2 to 1.5 bar.Close the valves tightly and restart the boiler.

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