Medium
4 07 on Ariston Clas HE 35

Your boiler is struggling to read the temperature because the connection to your thermostat or the internal room sensor is faulty or disconnected.

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

Room sensor circuit open/short circuit

From this model's manual
Verified against the Ariston Clas He 24 installation & service manual, page 37.
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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