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Glow-worm F28 Error / Fault Code Explained

Glow-worm Error Codes

A Glow-worm boiler displaying the F28 error code has failed to ignite and there are many potential causes.

F28 is a fault code that could appear on any Glow-worm boiler, including the Energy range, and always means the same thing.

Glow-worm boiler error code Meaning
F28 Ignition unsuccessful when starting up.

Glow-worm F28 error code causes

As we mentioned earlier in the article, there could be any number of reasons why the F28 error code has appeared on a Glow-worm boiler, which means that you'll need a Gas Safe engineer to find and resolve the fault.

Some of the potential issues that can lead to ignition failure include:

  • Not enough gas being supplied to the boiler
  • Frozen condensate pipe
  • Debris in the burner
  • Broken spark generator.

There are many other faults that could lead to ignition failure, all of which would need a Gas Safe engineer to diagnose and repair, but these are some of the most common.

Fixing the Glow-worm F28 error code

Out of the potential issues we've listed, a frozen condensate pipe is the only one you could attempt to resolve yourself. The condensate pipe is a plastic pipe that you'll find outside (close to where the boiler is installed) that sits above a drain. The purpose of this pipe is to expel potentially harmful gases out of the home.

Being outside means that the condensate pipe is susceptible to freezing during the winter months and need defrosting as a result. To do this, you should pour warm (not boiling) water from the kettle over the blocked part of the condensate pipe. For a full walkthrough, follow our step-by-step guide to thawing a condensate pipe.

If you don't feel confident defrosting the condensate pipe yourself or are in the slightest bit unsure what's causing the F28 fault, you need to contact a Gas Safe engineer.

Finding a Gas Safe engineer

Gas Safe engineers are the only people who can work on gas boilers by law which means that you need to hire one to resolve the F28 error code on your Glow-worm boiler.

If you're not sure where to start when it comes to finding a Gas Safe engineer, complete one of our simple online forms and up to 3 Gas Safe engineers will get in touch with you to provide free boiler repair quotes.
Once you've received all of the quotes, you're free to compare and choose the one that's best for you.

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Boiler Guide Team

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Boiler Guide Team

Boiler Guide has been home to a host of heating experts who have helped millions of UK homeowners searching for advice and guidance. If you’ve got heating questions, we’ll have the answers.

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