High
133 on Baxi 636 COMBI

Your boiler has failed to light because it cannot detect a steady gas flame to keep it running.

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

indicates that the gas supply has been interrupted, ignition has failed or the flame has not been detected.

From this model's manual
Verified against the Baxi/Baxi 636 Combi Lpg 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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Related fault codes

E133View →119View →110View →

All 17 fault codes on the 636 COMBI

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

0915202840109110118125128130134135160321384

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