High
E133 on Main Eco Elite

Your boiler has tried to ignite but cannot get a steady gas supply or sense a flame, which means it has locked itself out for safety.

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

Gas supply error or flame failure

From this model's manual
Verified against the Main Eco Elite 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 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

E128View →E133View →E168View →

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