Low
05 on Chaffoteaux Calydra 23 Green

Your boiler has detected very cold temperatures and is circulating water to prevent the internal pipes from freezing.

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

Anti freezing system, pump on

From this model's manual
Verified against the Chaffoteaux Calydra 23 Green installation & service manual, page 17.
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

Ensure the boiler remains switched on at the mains powerCheck that your room thermostat is turned upEnsure any exposed pipes in unheated areas like garages are adequately insulated

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