Medium
84 on Ideal Evomax 30

Your boiler's hot water cylinder sensor is not working properly, which means it cannot accurately monitor the temperature of your stored hot water.

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

Cylinder Thermistor Fault

From this model's manual
Verified against the Ideal/Ideal Gc No 41 750 38a 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

83View →85View →

All 7 fault codes on the Evomax 30

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

8081828385Error 20

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