Medium
Indicator Neons on Baxi Promax Ultra

Your boiler uses a system of flashing or steady lights to tell you what part of the heating cycle it is in or if it has encountered an error that needs attention.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse 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).

DIY fix possible

Check if the Power on neon is illuminated greenIdentify if any lights are flashing red, indicating a lockoutTurn the selector switch to the 'Reset' position for five seconds and release

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