High
E05 on Warmflow Agentis External

Your boiler has lost connection with a internal temperature sensor, meaning it cannot safely tell how hot the water is and has shut down as a precaution.

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

Boiler NTC Error — flow NTC temperature sensor short circuit or disconnected; consult Service Engineer

From this model's manual
Verified against the Warmflow Agentis Internal installation & service manual, page 136.
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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