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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Keston C36p installation & service manual, page 32.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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