High
E33 on Keston C36p

Your boiler has lost the connection to the sensor that monitors your hot water temperature, meaning it cannot reliably heat your taps.

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

DHW sensor open circuit - check connections to DHW sensor are in place

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

E32View →E34View →

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