Low
05 on Chaffoteaux Calydra 24 Green

Your boiler has detected that the internal water temperature is very low and has automatically turned on the pump to prevent the 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/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 power supply remains switched onCheck that the gas supply is activeIncrease the room thermostat temperature slightly to encourage the boiler to fire upCheck that any external condensate pipes are not frozen or blocked

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Related fault codes

06View →07View →

All 22 fault codes on the Calydra 24 Green

Seeing a different code? Every code this model can display, in one place.

0101 to 990306070809101112182023242526293132Noises in CH systemRed indicator lit

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