High
Indicator Neons on Baxi Promax Heat

Your boiler is using a combination of flashing or steady lights to signal exactly what is wrong with the system, ranging from simple pressure issues to internal component failure.

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

Used to monitor the boiler operation and identify potential fault conditions as part of the Fault Finding section (detailed in Section 13.0).

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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