High
E80 on ECA Proteus Premix 24 HCH

Your boiler has detected that the water isn't circulating properly between the heating system and the unit, causing a temperature mismatch.

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

Temperature Difference Error between CH Return Water Temperature and CH Supply Water Temperature

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.

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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