High
E10 on Warmhaus Enerwa

Your boiler is struggling to accurately read the temperature of the water returning to it, so it has stopped working to prevent potential damage.

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

Central heating temperature RETURN sensor faulty

From this model's manual
Verified against the Warmhaus Enerwa installation & service manual, page 59.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's control board loses communication with the auxiliary temperature sensor or receives an implausible reading. The most common reason is an electrical failure within the sensor itself, or damaged wiring that prevents the signal from reaching the main computer.

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

E09View →E11View →

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