Last updated on October 6th, 2024
The Glow-worm F29 fault code will show on the boiler’s screen when there is a problem and it locks out. Glow-worm uses them to show you what might be wrong with the boiler not firing up.
I have been carrying out boiler repairs full-time for over a decade and having fault codes on the screen when I arrive is very welcome.
What Does F29 Mean?
Here is what the Glow-worm manual says about the F.29 fault code:
The most likely cause of an F29 fault is the boiler has been locked out due to a gas supply fault or a blocked condensate pipe. It could also mean that a part on the boiler is broken and needs to be replaced, but most of the time it is a gas supply issue.
How to Fix an F29 Fault
To fix this fault the first thing I would do is check:
- The gas is turned on at the gas meter
- If you have a prepayment gas meter, then make sure you are in credit, as this is quite a common situation I come across
- If you have other gas appliances, like a gas hob or gas fire, check to see if these are working to find out if you have a gas problem. If they don’t work, then you have a gas supply problem
- Check for a blocked or frozen condensate pipe
Other Causes of an F29 Fault
A gas supply problem is the most common cause , but here are some other potential causes:
- Faulty gas valve: Might need a new one
- Worn-out spark electrodes: Might need to be cleaned or replaced
- Faulty PCB (printed circuit board): The PCB is the brain of the boiler and might need to be replaced
- Frozen condensate pipe: If it’s freezing outside, having a frozen condensate pipe is possible. You can pour hot water on it to melt the frozen condensate and reset the boiler.
Gas Pressure
Low gas pressure (or no gas) is a common cause of an F29 fault. You need to make sure you’re getting enough gas but low gas pressure can also be caused by a faulty gas valve.
You can do all the checks needed to find out if you’re getting enough gas but you might need to get a Gas Safe engineer in to replace a faulty gas valve. You also might need to call your gas supplier if your other gas appliances aren’t working as there might be a problem with your gas meter or a gas pipe problem in the street.
Glow-worm Fault Reset
The first thing I would do on a Glow-worm boiler that is not working, no matter what fault code is showing, is to check the pressure and reset the boiler.
Knowing how to reset a boiler is the simplest way to get your boiler working again, as it might have just locked out. To reset a Glow-worm boiler, you must find the reset button. This is usually a flame with a line through it. You have to press the button to reset the boiler. Sometimes you have to hold it down for 3 seconds, but on some, it just needs to be pressed.
Glow-worm Boiler Guides
Summary
A Glow-worm F29 error on your boiler can be easily fixed without opening the boiler. Make sure to verify you are getting gas by checking the gas meter ECV and that you have credit if you use a pre-payment gas meter. If it’s freezing outside then you probably have a frozen condensate pipe.
If it’s not any of these problems then it’s probably a gas valve or PCB problem which you’ll need to call a Gas Safe engineer to fix.
Feel free to ask any questions in the comments below, and I’ll do my best to help. If you found this post helpful, please consider sharing it.
