What does the Glow-worm S.53 fault code mean?

Your boiler has temporarily stopped itself because it is struggling to move water around the system efficiently, likely due to low pressure.

How much does it cost to fix Glow-worm error code S.53?

Typical repair cost for the Glow-worm S.53 fault is £80-150 including labour.

Glow-worm S.53 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

The product is within the waiting period of the modulation block/operating block function as a result of low water pressure/water deficiency (flow/return spread too large).

Shared across the MicraCom range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

DIY fix possible

Check your boiler pressure gauge; if it is below 1.0 bar, you need to repressurise the systemLocate the filling loop (usually a silver braided hose under the boiler) and open the valves to let water inBring the pressure up to 1.5 bar, close the valves tightly, and restart the boiler

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Boiler cover options

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A cover plan would handle faults like S.53: no call-out fees, no surprise bills.

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Related fault codes

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All 138 fault codes on the MicraCom

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

Your boiler has temporarily stopped itself because it is struggling to move water around the system efficiently, likely due to low pressure.

What the manual says

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 138 fault codes on the MicraCom

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