High
1025 on Worcester Bosch 1000

Your boiler is struggling to accurately monitor the temperature of the water returning to it, so it has stopped working to prevent potential overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Return temp. sensor is faulty

What causes this fault?

Temperature sensor failure

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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