Glow Worm 30CXI dirty system


I have a Glow worm 30 CXI boiler, it currently shows F9 error message. I tired re-pressurizing the system, but it did not solve the issue. Any other idea how to solve F9 error?



Hi Ben

Did you try flushing your boiler? Glow worm boilers are very sensitive to the dirt and the sludge. Glow warm recommends particular chemicals to flush the system, and those really should be used if you want to have a smoothly working boiler. Flushing boiler takes a good few hours as you should stop only once the outcome liquid is transparent


Glow warm Ultimate fault code 9

Hi All,

I have a Glow warm UIHmate problem and it shows fault code 9. Any idea how to fix it? Do I really need to call a service guy? I don’t have an extra money now to fix it by someone else than me.


Hi Harry

F9 error codes mean issues with pressure, either circulation, boiler pressure or in worse case diverter valve problems. I am not sure which one is in your case, diverter valve should be changed by an experienced person, but boiler and circulation pressures could be adjusted on your own. Top the pressure yourself, you may also flush the boiler and if that doesn’t help call a specialist


Glow warm Betacom F61 and F64

Hi Guys,

I have a Glow warm boiler, the Betacom model, it is 4 years old, and I service it annually so I didn’t experience any issues with it. Actually a service guy was here 2 weeks ago, and it looks like the begining of my trouble with the boiler, because since then every now and then it is showing errors F61 or F64, but restating helps. I am just worried that one day it won’t… Any thoughts what may cause faulty functionality here?


Hi Tom,

Sometimes during the service work- guys take of the front panel, cleans some parts- maybe simply a PCB connecting cable got trapped when putting back boiler together. Actually it is not so rare as you may thing. I would call this service guy asking him to come, explain what is happening, and ask him to check for the trapped cable. If that won’t be the case then the PCB itself will need to be replaced, but I really vote for the cable. 


Flexicom CX range error code F14

Hi Folks

I have a Flexicom CX range Glow -warm boiler that is showing F14 error code. I tired restarting, no success, I tried switching off and on after an hour- no success. Manual says error F14 means defective gas valve. Is it enough to purchase a spare one, and find a manual and replace it myself?

Best Regards


Hi Luke

How old is your boiler? I would start from checking power supply to the gas valve from a PCB, because if there is no power between those then it is not a gas valve issue, but faulty wiring or/and PCB. It is not an easy thing to check and replace yourself, so I would rather advice you to call a Gas Safe Registered engineer



Glow warm Flexicom CX no hot water


I am an old Glow-warm boiler model Flexicom CX. Boiler was working fine for year, but started to get crazy during last weeks. Every now and then it switches off showing error code: F1, F3 or F4. Each time it picked-up a normal functionality after restarting. Unfortunately- it looks that it won’t be the case today. Any idea how to fix it, preferably permanently?


Hi John

F3 code starts for fan fault, F1 and F4 stand for ignition fault. Having those appearing from time to time my guess would be PCB fault, which is actually common issue with this type of boiler. Fan will need to be replaced to. Personally I wouldn’t replace PCB on my own, as it is complicated to make right all the connections, but you decide. 

Glow-worm Ci F16 fault

Hi All

I have a Glow-worm boiler, model Ci, it is no longer under warranty. Honestly we never had problems with it, till today. We woke up and we realized that there is no hot water. Boiler display F16 error code. I tried resetting, no success. I can’t find user manual to figure out what does it mean and how to fix it? Can someone help?



Hi Rob,

Error F16 means a fault with flame detection. It is pretty serious fault, so I would advice calling a service guy, that will most probably clean or/and replace probe as well as lead and flame detection. Unfortunately this is a pretty common fault on Ci models.