Emergency
F.26 on Glow-worm Energy 35 Store

Your boiler has detected an issue with the internal gas valve, meaning it cannot safely control the supply of gas required to heat your home and water.

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 without function

From this model's manual
Verified against the Glow Worm/Glow Worm Energy 35 Store Installation And Maintenance Instruc 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 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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Related fault codes

F.27View →F.28View →F.29View →

All 72 fault codes on the Energy 35 Store

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

F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.27F.28F.29F.32F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.77F.79F.81F.83F.84F.85F.86F22S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.53S.54S.96S.98S.99

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