glow worm 18hxi F1 fault help

[roundstone]

Hi
I have a glow worm 18 hxi keep getting F1 fault some times it will run and work fine.
The next time it will go to start up the green light comes on for 3 secs and click click click
light goes out and F1 red light flashes. you can turn it on and off 10 times then it will run fine. until the next time it wants to heat up the water or radiators.


any advice Many thanks

 

[macackau]

Get a gas safe registered engineer to come take a look. Where do you live? Someone on here might be able to help