Low
E33 on ECA Proteus Premix 24 HCH

Your boiler is having trouble communicating with the sensor that monitors the temperature outside, which may cause your heating to run at the wrong temperature.

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.

What the manual says

Manufacturer manual

Outdoor temperature sensor failure

From this model's manual
Verified against the Eca Proteus Premix 24 Hch installation & service manual, page 38.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the external temperature sensor on your outside wall if you have one.Inspect the sensor and the visible wiring for any obvious signs of damage or loose connections.Press the Reset button on the boiler control panel to see if the fault clears.

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Related fault codes

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