BoilerFaultCodesWhat the manual says
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From this model's manual
Verified against the Glow Worm/Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
What causes this fault?
This code appears because your boiler is functioning exactly as it should and the burner is currently firing to provide heat. It is simply a status update letting you know that gas is being burned to heat the water for your taps or radiators. You do not need to take any action, as this is a sign of normal operation.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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Related fault codes
All 51 fault codes on the Ultracom cxi
Seeing a different code? Every code this model can display, in one place.