High
260 on Worcester Bosch Junior 24i

Your boiler has started up but is not detecting the expected heat increase, which often means the water isn't moving correctly or a sensor is failing.

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

The flow temperature sensor is not detecting a rise in temperature following a burner start

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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Related fault codes

A7View →E9View →

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