Medium
F12 on Ferroli Bluehelix Tech RRT 24C

Your boiler is struggling to detect the temperature of the water used for your taps and shower, so it has stopped heating your hot water to prevent it from getting too hot.

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

DHW sensor fault

From this model's manual
Verified against the Ferroli Bluehelix Tech Rrt 24c installation & service manual, page 43.
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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