Low Warning
Fault 53 125 on Worcester Bosch Greenstar CDi Compact

Your boiler's solar heating sensor has detected an issue, likely meaning your solar panels aren't assisting with your hot water production as they should.

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

Collector temperature sensor (T1) fitted on collector array inlet.

What causes this fault?

This fault occurs when the boiler loses communication with the sensor located on your solar thermal panels. The most common reason is that the sensor itself has failed due to extreme outdoor temperatures or the wiring connecting the panels to your boiler has become damaged or loose.

This fault is more frequently detected during peak summer months when high collector temperatures can stress an aging sensor or cause it to fail.

Engineer required

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

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