Glow-Worm Boiler F2 Fault Code
The Glow-Worm fault code F2 relates to PCB and here we have Q & A or require an engineer for an emergency boiler repair.
The Glow-Worm Boiler Fault Code F2 Error Common Q & A
Just below, we have a list of common questions relating to the F2 fault code on the Glow-Worm Boiler.
- What does the F2 fault code mean on my Glow-Worm boiler?
- Is my boiler dangerous if it has a fan fault?
- Why does my boiler fail to ignite when there’s a fan fault?
- What could be the cause of the F2 fan fault on my Glow-Worm boiler?
- How are excessive vibrations caused, and how can that affect the fan on my Glow-Worm boiler?
- How do leaks occur, and what problems could they cause with my fan?
- How does the wrong fan speed lead to the F2 fault code being displayed?
- How will my boiler engineer know if the fan on my Glow-Worm boiler is faulty?
- Is there anything else that could be causing the F2 fault to be displayed on my Glow-Worm boiler?
What does the F2 fault code mean on my Glow-Worm boiler
When your Glow-Worm boiler develops a problem, it will show a fault code on the display panel. It’s the printed circuit board (PCB) that decides on the most relevant fault code to be shown.
It’s these fault codes that help Gas Safe engineers to determine what the problem is. Without these fault codes, they’d have to spend hours testing every single part on your boiler.
The F2 fault code on Glow-Worm boilers relates to a fan fault. And, although there are various things that can affect the operation of the fan, this is the component your boiler repair company is going to start with.
Is my boiler dangerous if it has a fan fault
The fan in your Glow-Worm boiler is incredibly important. When the burner kicks into life, harmful gases are created. Some are condensed and taken out of your boiler via the condensate pipe. The others are vented via the flue. It’s the fan that creates a draught, helping these gases to quickly escape via the flue.
If the fan isn’t working at the correct speed, or isn’t working at all, gases aren’t able to escape from the boiler. If it continued to operate, the boiler would be dangerous. However, it’s likely that your boiler has locked out. In it’s locked out state, it’s unlikely to be dangerous.
And, that’s why your boiler engineer will tell you not to reset your boiler. On some occasions, a reset might trick your boiler’s PCB into thinking the problem has been fixed. Although it should quickly recognise that isn’t the case and lock out again, for the few minutes it’s operational, it could be dangerous.
Why does my boiler fail to ignite when there’s a fan fault
As we’ve already mentioned, a boiler without an operational fan can be dangerous. So much so, that a boiler won’t ignite without the fan kicking into life first. When you call for heating or hot water, your boiler’s PCB asks the fan to start up.
The air pressure switch is looking for a change in air pressure, to determine that the fan is working. If it doesn’t see this air pressure change, it feeds back this information to the PCB, to tell it that the fan isn’t working. The PCB deems this as being unsafe and will fail to provide gas to the burner.
What could be the cause of the F2 fan fault on my Glow-Worm boiler
It goes without saying, that a lot of faults on boilers simply develop due to old age. But, that’s not always the case. The cause of the fan fault on your Glow-Worm boiler could be:
- Excessive vibrations, causing loose or damaged connections
- Leaking boiler components, ruining electronics
- Incorrect fan speed
- Faulty fan unit
How are excessive vibrations caused, and how can that affect the fan on my Glow-Worm boiler
It’s natural for a boiler to vibrate a little. After all, there are lots of moving components. However, if you’ve noticed that your boiler has been noisier than usual lately, there’s a good chance that there’s a problem.
What your Gas Safe boiler repair company will be looking out for, is components that use bearings. That means they’ll be looking at the fan, but the pump as well. These both spin on a shaft and bearings. As both the parts wear, they don’t run as smoothly, and this can cause them to vibrate, creating much more noise than usual.
Once bearings start to deteriorate, they do so quickly. The bearings themselves, are relatively easy to replace. However, the sooner they’re replaced the better, as the excess vibrations being caused, can lead to damaged connections, and sometimes that that ends up in a boiler component that’s completely ruined.
Your boiler engineer will need to check both the fan and pump. If bearings need to be replaced, that’s their first job. However, they also need to check the state of wiring and connections. If either are damaged or not secure, it’s likely the signal between the fan or pump to the PCB is intermittent, and that’s going to mean more boiler problems.
How do leaks occur, and what problems could they cause with my fan
The next thing for your boiler engineer to check if you have a fan fault, is for boiler leaks. When there are any problems with electronic components, there’s a good chance that water damage is to blame. This moisture leaks onto electrical components, wiring and connections and causes them to work intermittently, or fail completely.
Components your boiler engineer is most likely to focus on, is the pump and the heat exchanger.
The pump will leak if the seals burst. And, if it’s been set on too high a speed setting, or has been blocked due to heating sludge, this is a huge possibility.
The seals on the pump can be replaced to fix the leak. But, your boiler engineer will want to check that the leak isn’t going to occur again. That means setting the pump to the right speed, and removing all signs of central heating sludge, which is the main culprit for blockages.
Another component they’ll focus on, is the heat exchanger. If there’s sludge in the heating pump, there’s a good chance that there’s limescale build-up on the heat exchanger. When limescale builds up on the heat exchanger, it can lead to cracks, and that’s going to spring a leak.
It’s unlikely a heat exchanger can be repaired, and a replacement can be more than £450.
Regardless of the repair, your boiler engineer will want to protect your boiler, so this doesn’t happen again. To protect from heating sludge, they’ll want to run a hot flush, dose the system with inhibitor and fit a magnetic boiler filter.
And, for limescale, they can fit a scale reducer, which catches limescale before it makes its way to the heat exchanger.
How does the wrong fan speed lead to the F2 fault code being displayed
Your fan needs to be powerful enough to push gases out of the flue. We’ve been asked lots of times before whether strong winds can blow out the pilot light on the boiler. Unless the flue is in the direct path of that wind (unlikely), the answer is no.
But, what can happen, is a small backdraught in the flue. If your fan speed is too slow, a small backdraught from wind is going to counter the draught pushing gases out of the flue. To the air pressure switch, this effectively looks like the fan isn’t operational.
So, the pilot light doesn’t get blown out. Instead, the air pressure switch tells the PCB that the fan isn’t working, even when it is. The boiler locks out, and cuts supply of gas to the pilot jet in the process, making it look like the wind has blown out the pilot light.
Your boiler engineer will be able to check your fan speed, the position of your flue, and adjust the fan speed to ensure this doesn’t happen again. Once they’re happy, they’ll be able to reset your boiler, which will clear the F2 fault code from the display panel.
How will my boiler engineer know if the fan on my Glow-Worm boiler is faulty
Not all F2 fan faults can be fixed. On some occasions, the internals of the fan are just too worn, and it makes no sense to spend money repairing a tired fan, when replacements are available.
But, a fan isn’t a cheap component to replace. So, your boiler engineer will need to check over the component thoroughly. That means running tests for power using a multi-meter and checking all wiring and connections.
And, they’ll want to ensure that the PCB isn’t to blame. Any electrical fault could be PCB related. The PCB controls all electronic components in your Glow-Worm boiler. So, if the PCB isn’t working correctly, the fault code being displayed might not be the most relevant, and the PCB might be the component that needs replacing, not the fan.
After all checks, if your boiler engineer decides it is the fan that needs replacing, you should expect to pay around £250.
Is there anything else that could be causing the F2 fault to be displayed on my Glow-Worm boiler
Anything that is connected to the fan’s operation, could be a culprit. So, you’ll want to get your boiler engineer to check components like the air pressure switch.
The air pressure switch determines whether the fan is working. If that’s not working correctly, there’s a chance it’s signalling to the PCB that the fan isn’t working, even if it is.
And, as a last-ditch resort, they’ll also want to check for blockages in both the flue, and the condensate pipe. If there is any blockage, the boiler won’t ignite, so the fan doesn’t need to be operational.
Other Glow Worm boiler issues
For more boiler issues regarding the Glow Worm then please visit the Glow Worm Boiler Problems And Cures page.
We have more on printed circuit boards problems.