BoilerFaultCodes.com

Glow-worm 23C Fault Codes

Combi Natural Gas 23 kW 1994-1997 Discontinued
GC Number: 47-313-11

Replaced by: Compact 24

This boiler uses LED flash patterns

Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →

Most common fault codes

A flashing warning light on control panel
Your boiler has shut down and stopped providing heating and hot water because it has detected a safety issue, likely involving gas supply, air flow, or overheating.
May be DIY safe · £120-280
No flashing warning light on control panel
Your boiler has no power and is completely unresponsive, meaning it cannot provide any heating or hot water.
May be DIY safe · £100-350
Red flashing light
Your boiler has stopped working to protect itself and simply needs to be restarted to clear a temporary error.
May be DIY safe · £0-120

All 6 fault codes

Code Severity Plain English
A flashing warning light on control panel High Your boiler has shut down and stopped providing heating and hot water because it has detected a safety issue, likely involving gas supply, air flow, or overheating.
No flashing warning light on control panel High Your boiler has no power and is completely unresponsive, meaning it cannot provide any heating or hot water.
Red flashing light High Your boiler has stopped working to protect itself and simply needs to be restarted to clear a temporary error.
Red flashing light (Flue) High Your boiler has detected a blockage in the exhaust pipe or a problem with the fan, causing the system to shut down for safety.
Red flashing light (Gas) High Your boiler has stopped working because it cannot get a steady supply of gas to stay lit.
Warning light flash (after 45 seconds) High Your boiler is failing to start up because the internal fan, which clears waste gases, is not spinning.

Glow-worm 23C is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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