Medium
E 27 on Chaffoteaux Minima HE System 30

Your boiler has detected an issue with the sensor responsible for monitoring your hot water cylinder, which means it cannot accurately determine if your water is at the correct temperature.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Tank fault warning

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E 28View →E 29View →

All 34 fault codes on the Minima HE System 30

Seeing a different code? Every code this model can display, in one place.

A 01A 03A 36A 37A 39A 40A 41E 02E 04E 05E 06E 07E 08E 11E 12E 13E 14E 15E 16E 18E 20E 22E 23E 25E 26E 29E 30E 33E 34E 35E 36E 37E 38

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