Low
4 green flashes on Main Eco Elite

Your boiler is having a temporary 'handshake' problem between its internal computers and will usually try to fix 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

Communication error between printed circuit board (PCB) and control. 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 30 minutes to see if the error clears itself as it is a temporary communication faultTurn the selector switch to the reset position for five secondsSwitch the main electrical power to the boiler off and back on again

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