High
26 on Ideal Mexico Super 100FF / 125FF

Your boiler has successfully lit its small starter flame, but the main burner is failing to ignite because the gas valve is not opening to supply the necessary fuel.

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

PILOT LIT BUT NO MAINS GAS

From this model's manual
Verified against the Ideal Mexico Super 100ff 125ff System 3 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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