Low
ERR>CM on Alpha E-Tec R

Your boiler's wireless controller has momentarily lost contact with the unit, usually because the boiler was switched off at the mains.

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.

Technical description

Connection error symbol displayed on Climatic control if the boiler is switched 'off'

DIY fix possible

Ensure the main power supply to the boiler is switched back on.Wait a few minutes for the wireless connection to re-establish automatically.If the message persists, restart your control unit or check its battery levels.

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