Low Warning
51133 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a fault with the solar collector temperature sensor, meaning it cannot correctly monitor heat coming from your solar panels.

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

Temperature sensor type PTC 1000 used as collector temperature sensor (T1).

What causes this fault?

This fault occurs when the boiler loses communication with the sensor that monitors the heat of your solar panels. It is usually caused by the sensor itself failing due to long-term exposure to extreme temperatures or a break in the wiring connecting the panels to the boiler. As a result, the system cannot safely determine if there is enough solar energy available to heat your water.

This fault is more common during the summer months when solar collectors reach their highest temperatures, which can stress or perish aging sensors.

Engineer required

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

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