Technical description
Normal operation (mains supply tracking/standby)
What causes this fault?
This is not actually a fault, but the boiler's way of telling you it has a healthy power supply. The blinking green light indicates that the system is in stand-by mode and is ready to provide heat or hot water as soon as you turn a tap on or the thermostat calls for it.
DIY fix possible
No action requiredEnsure your thermostat is calling for heat if you want the boiler to fire up
Find a Gas Safe engineer
Search the official register →