Emergency
F.88 on Glow-worm Flexicom 24c / 28c

Your boiler has lost its electrical connection to the part that controls the gas supply, meaning it cannot safely start up to heat your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Fault: Gas valve assembly (Gas valve assembly not connected, connected incorrectly, or short circuit in the cable harness)

From this model's manual
Verified against the Glow Worm Flexicom 24c 28c installation & service manual, page 51.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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