Low
522 on Worcester Bosch 1000

Your boiler is currently performing a routine self-check of its temperature sensors to ensure it is operating safely and accurately.

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

NTC Drift Test is running

What causes this fault?

Sensor calibration test

Engineer required

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

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