Low
5 green flashes on Baxi Suprima 40

Your boiler is experiencing a temporary computer glitch and is trying to correct itself automatically.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Parameter error on printed circuit board (PCB). Temporary error, will self reset

From this model's manual
This code was read directly from the manufacturer service manual for this model.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for the boiler to complete its self-reset processIf the flashing continues for more than 10 minutes, turn the power off and back on at the fused spur switchMonitor the boiler to see if the fault recurs frequently

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