High Lockout
E133 on Baxi Platinum Heat

Your boiler is not receiving enough gas or is struggling to light the flame needed to heat your water and radiators.

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.

Technical description

Gas supply error or flame failure

What causes this fault?

This fault occurs when the boiler tries to ignite three times but fails to establish or maintain a steady flame. The most common reasons are an interruption in the gas supply, a blocked pipe, or a component inside the boiler being unable to create the spark needed to light the gas.

This fault is frequently seen during extreme cold snaps, as the external condensate pipe can freeze and back up, preventing the boiler from lighting safely.

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

E110View →

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