BoilerFaultCodesWhat the manual says
Manufacturer manual‘MAINS’
From this model's manual
Verified against the Glow Worm Swift Flow 100 installation & service manual.
What causes this fault?
The orange light indicates that the boiler is receiving a live electrical supply and the main switch is set to the 'on' position. This is a normal operational status and does not represent a physical failure or a broken part. If your boiler is not providing heating despite this light being on, it usually means the system is simply waiting for a command from your thermostat or timer.
DIY fix possible
Check that the power switch on the wall or fused spur is turned onEnsure your room thermostat is turned up high enough to call for heatCheck if any timers or programmers are set to an 'ON' period
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