High
E57-049 on Ideal Mini C28

Your boiler is having difficulty transferring heat to your hot water supply, likely due to a blockage or a leak within the internal heat exchanger component.

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 heat exchanger+’O’rings (mod. miniHEC28)

From this model's manual
Verified against the Ideal Mini He installation & service manual.
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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