High
Neon 2 on Glow-worm Space Saver Compleheat 30 40 50

Your boiler has automatically shut down because it has detected that it is getting too hot inside, likely because the water is not circulating as it should.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Control thermostat overheat or pump failure cut-off devices operated. Faulty pump.

From this model's manual
Verified against the Glow Worm Space Saver Compleheat 30 40 50 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.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Neon 1View →Neon 3View →

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