High
E57-048 on Ideal Mini C28

Your boiler is struggling to heat your tap water because an internal seal or flow component is faulty, causing the system to stop working properly.

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. miniHEC24)

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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