High
578 on Worcester Bosch 1000

Your boiler has detected a faulty sensor that monitors temperatures, meaning it cannot safely control its heat output and has shut down to protect itself.

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

NTC is damaged

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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