High
Central Heating LED flashing on Heatline Capriz 25 System

Your boiler has lost the ability to accurately measure the temperature of the water being sent to your radiators, so it has shut down to prevent the system from getting too hot.

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

Fault on Central Heating NTC (10-12 kohms @ 20 ºC)

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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