High
E163 on Baxi Suprima 115

Your boiler has lost its connection to the hot water temperature sensor, meaning it cannot monitor how hot the water is and will likely stop producing hot water for safety.

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

Domestic hot water (DHW) negative temperature coefficient (NTC) thermostat sensor fault (s.c.) or DHW NTC sensor fault (o.c.).

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

E131View →

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