Medium
S.96 on Glow-worm Compact

Your boiler is currently running a background safety check on its internal sensors and has temporarily prevented the heating and hot water from turning on while it completes this process.

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

The self-test for the return temperature sensor is activated. Heat demands are blocked.

From this model's manual
Verified against the Glow Worm Compact 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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