Medium
S.39 on Glow-worm Easicom3 System

Your boiler has detected that the safety circuit for your underfloor heating system is open, meaning it has paused operation to prevent any potential damage.

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

Underfloorheatingcontactopen

From this model's manual
Verified against the Glow Worm Easicom3 System installation & service manual, page 42.
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

S.37View →F.39View →

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