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F.86

Glow-worm fault code

Glow-worm F.86: underfloor heating contact fault

Engineer only

Glow-worm describes F.86 on Betacom A range boilers as: underfloor heating contact fault.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to: Betacom A range. Codes can differ between models, so check your manual.

From Glow-worm's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

Model	Meaning
Betacom A range	Underfloor heating contact fault

Can I fix Glow-worm F.86 myself?

No. It needs a Gas Safe registered engineer to diagnose. Tell them the exact code and your boiler's model name.