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

Your boiler is temporarily pausing its heating cycle because it has detected that the water flow through your radiators is not moving as it should.

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

Typical repair cost for the Glow-worm S.53 fault is £90-180 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).

From this model's manual

Verified against the Glow Worm/Glow Worm Flexicom 24c 28c installation & service manual, page 46.

DIY fix possible

Check that all radiator valves throughout your home are fully openEnsure your system pressure gauge is reading between 1 and 1.5 barWait 15 minutes for the boiler to automatically reset itself once the flow improves

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Related fault codes

F.22View →F.23View →F.24View →

All 141 fault codes on the Flexicom 24c / 28c

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

d.00 d.01 d.02 d.05 d.06 d.08 d.09 d.10 d.11 d.13 d.14 d.15 d.16 d.17 d.18 d.20 d.21 d.22 d.23 d.27 d.28 d.33 d.34 d.35 d.36 d.39 d.40 d.41 d.43 d.45 d.47 d.50 d.51 d.58 d.60 d.61 d.62 d.64 d.65 d.67 d.68 d.69 d.71 d.80 d.81 d.82 d.83 d.85 d.88 d.90 d.93 d.94 d.96 F.00 F.01 F.10 F.11 F.13 F.20 F.22 F.23 F.24 F.25 F.27 F.28 F.29 F.32 F.33 F.46 F.49 F.61 F.62 F.63 F.64 F.65 F.67 F.68 F.70 F.71 F.72 F.73 F.74 F.76 F.77 F.78 F.83 F.84 F.85 F.86 F.87 F.88 F.89 F.97 F01 F10 F11 F13 F17 F20 F22 F25 S.00 S.01 S.02 S.03 S.04 S.05 S.06 S.07 S.08 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.39 S.41 S.42 S.46 S.54 S.58 S.76 S.88 S.91 S.96 S.98

Your boiler is temporarily pausing its heating cycle because it has detected that the water flow through your radiators is not moving as it should.

What the manual says

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 141 fault codes on the Flexicom 24c / 28c

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