Low Warning
81-65 on Daikin D2CND

Your boiler is still providing heating and hot water, but it has detected a problem with the temperature sensor for your solar thermal system.

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

Domestic hot water (DHW) temperature sensor error. The boiler will continue in operation but solar sensor has an error

What causes this fault?

This fault occurs when the boiler loses communication with the temperature sensor attached to your solar thermal panels. The most common reason is a physical break in the sensor's wiring or the sensor itself failing due to the extreme temperature fluctuations it experiences on the roof.

This fault is more common during the summer months when solar thermal systems are under peak thermal stress and high operating temperatures.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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