Medium
S.39 on Glow-worm Flexicom 24c / 28c

Your boiler has temporarily stopped firing because an external safety device, such as a condensate pump or a room thermostat, has signaled it to shut down.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

Burner off contact has triggered (e.g. surface-mounted thermostat or condensate pump)

From this model's manual
Verified against the Glow Worm Flexicom 24c 28c installation & service manual, page 46.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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