Medium
F.13 on Glow-worm Ultracom hxi

Your boiler has detected an electrical fault with the sensor that monitors the temperature of your hot water cylinder, meaning it cannot heat your water correctly.

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

Domestic hot water cylinder temperature sensor short circuit

From this model's manual
Verified against the Glow Worm Hxi System installation & service manual, page 34.
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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