My 38cxi is approx 3 years old and I have had the normal problems with the boiler. F14 which is an over temperature error, which generally means removing the heat exchanger and washing out the old lime scale and debris that has been in the system over the last 15 years. Which I cured by fitting a hydro flow coil near the boiler on the CH return, which I must say really works and worth the money I paid for it!
I was always stripping the boiler down practically every 8 weeks, now its only 1 once a year.

I now have a fault code of F13, which in the paper work that comes with the boiler. Indicates that it's a connection problem on the main PCB. I have reseated the all of the connections on the board several times and checked all the leads which all seem ok.
I have isolated the fault to the DH circuit, as if I turn off the hot water dial to zero and wait a few seconds the error is reset and if I return the dial to the required hot water setting I will get hot water again.
The error is intermittent and starting to get to me,
I suspect the main PCB, but over £125 I am reluctant to go and buy it, if it is not going to fix the problem.
Any Ideas or advice?

Andrew, March 2009

I have a glow worm boiler and it's also flashing f13. And the cylinder won't ignite. Does anyone have any ideas?

michael, September 2015

be a wise man with this code,first chek condensing drain,then chek mian heat exchanger on hot water is clean,then check mian boiler heat exchanger is clean as well,i found the boiler i fixed was full of iron fragmeants it took 4 or 5 strip downs and cleans shut the flow and return down on heating,then u will now when the boiler is clear,.the heat sensors will give u f13 when boiler is choked up with sluge and fragements if when u run hot water the flame goes up and down with water temperture stays at a constant rate u have a clean boiler if u get cold spells of water f13

roy the cowboy, September 2010

I now have the same symptoms. Did you find a solution Andrew?

Peter, September 2010

hi, i have the same problem with my 38cxi, i have taken the board off and checked it and it has scorch marks on the back so i suspect the pcb is, u/s. I have had no problems apart from this.

Dave, L., June 2010

Had the same fault on mine, had to replace board

steve carroll, May 2009

Thanks!

I will have a look, the fault always seems to appear when the CH is not on, even at night when it is just idling.

Andrew, March 2009

Similair fault with 24 cxi, fault that appeared was also intermitant and pointed towards wiring fault / pcb.When visually examined boiler (removing front casing and front panel to visually check fan/gas valve manifold and heat x),found HT lead and earth at ignition electrode to be heat damaged, this was caused by a poor seal/gasket around circular burner, so heated gases were escaping out of the heat x...check it out,if so its 'immediately dangerous' and should be isolated. glowworm replaced fault to seals and apparently sent out letters

papmcg, March 2009