High
ERROR CODE 5 on Ideal Excel HE

Your boiler's temperature sensor is providing incorrect readings, so it has shut down to prevent the water from getting too hot.

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

CH THERMISTOR FAULT

Shared across the Excel HE range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 12 fault codes on the Excel HE

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

Automatic ShutdownERROR CODE 1ERROR CODE 2ERROR CODE 3ERROR CODE 4ERROR CODE 6ERROR CODE 7ERROR CODE 8Ignition LockoutOverheat conditionRed operational light 2 (E)

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