Glow Worm F28 Fault Code: What it Means and How to Fix It

Just like any other boiler manufacturer, Glow Worm boilers come with a lot of built-in fault codes. The main function of these fault codes is to tell homeowners when there is a specific issue with their Glow Worm Boilers.

Additionally, you can use the Glow Worm boiler manual, which helps you find out more information about a specific glow worm error code that your boiler is currently displaying.

There are several reasons the F28 fault code may appear on your boiler. Let’s get started and understand what causes the F28 fault code on your Glow Worm Boiler.

What does F28 mean on a Glow Worm Boiler

The F28 Glow Worm Fault Code indicates that the ignition of the boiler was unsuccessful. There can be several causes for this. Moreover, the F28 fault code in your boiler doesn’t always tell the exact reason why the F28 persists. Let’s try to understand the causes for this fault code:

Essential Takeaways

• Glow Worm boilers show an F28 upon unsuccessful ignition attempts.
• Common causes include gas valve issues, electrical issues, frozen condensate pipe or burner residue.
• It is not recommended to DIY fix this issue and a Gas Safe Register engineer should be contacted.

Causes of the Glow Worm F28 Error Code

Following are the causes of the Glow Worm F28 error code:

Gas Valve Adjusted Improperly

An incorrect gas valve setting is one of the most common reasons for an F28 fault code. This essentially means that the sufficient amount of gas required to fire up the boiler cannot reach the burner.

Also, a faulty gas valve results in inconsistent gas flow to the burner. Therefore, an incorrect gas valve adjustment or a fault with your gas valve is one of the causes why your boiler shows an F28 error.

Restricted Airway in the Flue

The Glow worm f28 fault can also be caused by a blocked flue airway. Here, the issue can be with the flue or the condensate pipe. The blockage issue with the flue can happen from natural degradation over time.

Gas Pressure Level

For people with a new boiler, inconsistent gas pressure can be one of the reasons for an F28 fault code. This happens when your main gas supply can’t manage the surge in gas demand from your new boiler.

An air pocket can also be a common cause of reduced pressure in your gas supply.

Furthermore, in the winter season, your gas meter regulator can get frozen, which causes an F28 error code.

Electrode fault or Ignition lead Issue

An F28 can also result simply from a boiler wiring fault. These issues are normal and result from moisture buildup and wear and tear. Additionally, boiler vibrations can cause ignition and electrode faults.

Spark Generator Issue

Another electrical issue that causes the F28 fault code. The spark generator has the job to spark the burner, which, when supplied with gas, causes boiler ignition. As this is a vital component in the boiler ignition process, a defective spark generator must be replaced.

PCB Malfunction

A Printed Circuit Board directs and controls various electrical components of your boiler. You can think of it as the electronic control unit of your boiler.

A defective PCB means your boiler is not receiving accurate signals. Here, the boiler can display a variety of fault codes, including an F28.

However, if your PCB is damaged beyond repair, your boiler will stop functioning because it cannot operate without it.

Burner Residue

Residue or debris in your burner can also prevent ignition. Mostly, this means that carbon blockage is hindering boiler ignition. The burner jet is a small component, so only a handful amount of carbon residue can trigger a glow worm f28 error.

Frozen Condensate Pipe

This issue occurs mostly during the winter season. When this happens, the water inside the pipe freezes, completely blocking the pipe. This stops your boiler from functioning properly.

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Is It Safe to Troubleshoot an F28 Fault DIY

It is not recommended to attempt fixing an F28 fault DIY. If a frozen condensate pipe is causing this issue, only then should you attempt to fix it yourself. Even as you resolve this issue, we recommend proceeding with caution. After successfully melting the frozen condensate, reset your glow-worm boiler according to the manufacturer’s instructions.

Now, let’s look at average costs for boiler component repair and replacement.

Average Costs for Boiler Components Repair and Replacement

Note: These figures show an average amount of costs and may vary depending on your region in the UK.

Key Considerations

Labour costs for Gas Safe engineers are normally £50-£80 per hour. However, complex jobs such as PCB fitting and flue replacement may require several hours. Also, note that the London/Southeast area tends to be at the higher end of cost ranges.

If your boiler is under the manufacturer’s warranty, many of these repairs might be covered. More importantly, a boiler cover can save you from any unexpected repair bills.

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Will the Glow Worm Guarantee Cover Repairs and Replacement Work for an F28 Error Code?

It is important to note that Glow Worm only covers the cost of boiler repairs and replacements if there is a problem with the manufactured part itself. In addition, your guarantee should still be valid and not expired.

If you meet Glow Worm’s terms and conditions, then their Service Engineer will perform the repair:

• The boiler should have been installed and commissioned by a Gas Safe Register engineer, and this must have happened within six months of the boiler being delivered.
• A Gas Safe Engineer should annually service your boiler, in accordance with the Glow Worm’s instructions.
• You must register your warranty within 30 days of the installation of your boiler. Failing to meet these criteria will revert your guarantee to a 12-month timeframe from the installation date. This means that if you had a five-year guarantee and you fail to register it, you will be left with a one-year guarantee.

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Conclusion

The Glow Worm f28 fault can be really frustrating in winter, leaving you without hot water and central heating. Whether it’s ignition issues or faulty electrodes, it’s important to decide on repair or replacement at the earliest opportunity. You can, however, fix the frozen condensate pipe yourself or reset the boiler to check if the problem is resolved. In addition, it is recommended that you contact a qualified Gas Safe Register engineer to resolve your Glow Worm F28 error and have your boiler serviced on time as well.