Medium
08 on Saunier Duval Isomax F30E

Your boiler's hot water storage tank sensor is failing to report the correct temperature, which might lead to inconsistent or no 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

Storage vessel thermistor/wiring fault

From this model's manual
Verified against the Saunier Duval Isomax F30e installation & service manual, page 31.
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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