BoilerFaultCodes.com
5 green flashes Low Warning

Your boiler has experienced a brief digital hiccup or settings error and is attempting to fix itself automatically.

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.

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

What causes this fault?

This fault occurs when the boiler's internal computer experiences a brief communication error or a temporary glitch in its stored settings. It is often caused by a minor power fluctuation or a digital 'hiccup' where the board fails to read its own configuration data for a split second. The boiler usually detects this inconsistency and performs an automatic reboot to clear the error.

Typical repair cost £0-350 (including labour)

DIY fix possible

Wait for the boiler to complete its automatic self-reset processMonitor the display to see if the flashing stops naturallyIf the flashing continues for more than 10 minutes, try turning the boiler off and back on at the fused spur switch

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A boiler cover plan would cover faults like 5 green flashes — no call-out fees, no surprises.

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