My mothers Glowworn 30ci Boiler stopped working the other day. There was a red light flashing and the fault code F4 on the display. I advised her to switch it off at the main power socket and switch it on again. This resulted in the boiler working again. I will be calling at my mothers home at the weekend and wish to know what caused the problem and can I do anything to stop that fault again. Is there something I can do to blead the system. There is a blus tap at the bottom of the boiler but I do not have the instruction book for the boiler. I would be very grateful for any advice.

Thanks John

John P, February 2008

my glow worm boiler has f4 flashing on it but it cant be the cold weather as its 28 degrees!

help, no hot water

td, May 2012

I had an F1 fault on my boiler. I pressed the reset button but it then showed F4. I rang British Gas and the customer service advisor told me to pour warm water over the small plastic outlet pipe which runs in to my drain. It was about -4 outside and the guy told me it was a common problem with condenser boilers in winter. The pipe freezes and so the boiler shuts down. I did it and then reset again and it worked fine.

Chanski, December 2010

If you go to the glow-worm website you can download the manual with all the codes etc.

Alastair, November 2008

hi,f4 fault code is a failure to ignite code.the boiler tries to ignite,(sequance of operation)and failes, the pcb then shuts the boiler down untill the user resets it,it can happen sometimes.with regard to the blue tap,there is a lcd disply on the boiler wich acts as a temprature and ch pressure gauge this should be set at1.1bar.to top the pressure up just turn the tap slowly anti clockwise then close when correct pressure reached.hope this helps

grant, February 2008