Glow-Worm Boiler Fault Code F28


Guscott Heating Services

glow worm boiler fault code f.28

What Does Does Boiler Fault Code F.28 Mean On A Glow Worm Boiler?

When this fault occurs, the F.28 error code displays on the control panel. With the cause actually being linked to a multitude of technical issues, it gives Gas Safe Registered Engineers direction of how to resolve the problem.

The F.28 could be a result of the following issues:

  • The Gas Meter running out of credit / no supply
  • Blocked Flue Airway
  • A Faulty Gas Valve
  • Faulty PCB Board
  • Low / No Gas Pressure
  • Faulty Spark Generator
  • Debris build up in the Burner
  • Faulty Electrode / Ignition Leads

Resetting the boiler may resolve the issue, however should it be one of the more technical issues listed above, called a Gas Safe Registered Engineer is essential.

With the first potential cause of running out of credit or having no supply of gas speak for itself, let’s explore the other potential causes in more depth.

What Can Affect The Gas Pressure On A Glow-Worm Boiler?

Interestingly, the age of your boiler can have an affect.

If it hasn’t been newly installed, the chances are there may be a ‘blockage’ in the form of an air pocket in the gas main.

If your boiler has been newly installed however and you are still experiencing the F.28 Boiler Fault Code, it might be that the gas mains can’t keep up with the new demand from the new boiler. Should this be the case, your Gas Safe Registered Boiler Installer will have to upgrade your gas main.

Other causes? Cold weather conditions may cause the gas meter’s regulator to freeze. A smart solution to prevent this from happening would be to box in your gas meter away from extreme weather conditions.

How Does The Flue Affect Gas Pressure?

Other than the condensate pipe, the other airway to consider would be the flue. 

A common mistake amongst less experienced Gas Engineers is fitting a flue without a flue guard. This often causes debris to create a blockage and can result in none / low gas pressure.

Debris can even find it’s way inside the flue which is something a registered gas engineer can strip down and clean. On the other hand, if the flue is breaking apart, it’s time for it to be replaced. 

Faulty Gas Valves

A healthy gas flow is key to a healthy ignition. Should it need adjusting, your Gas Engineer will first have to test the gas valve for any faults. Should there be any problems that need resolving, the boiler will need resetting once dealt with.

Faulty Ignition Leads / Electrodes

Boiler vibrations, moisture or old age can most definitely cause electrical faults within a boiler.

Experiencing boiler vibrations? It’s time to check the pump or fan if you’ve experienced a noisy boiler giving off vibrations, before ultimately stopping. The chances are that the vibrations have affected the smaller but equally important components that make up the boiler.

What about moisture?… Before changing the ignition leads or electrodes, checks for any moisture with the boiler must be carried out. There may be an internal leak which needs to be identified and dealt with before replacing any ignition leads or electrodes as these would be exposed to moisture again should the leak not be fixed. 

Last but not least, should the ignition leads or electrodes be old, the only solution is to have them replaced.

Debris Build Up In The Burner

Earlier we mentioned it could be the gas valve, but what if this is working fine – why am I still seeing the boiler error code F.28? It may be that the burner has become blocked with debris.

How does this happen? Chances are the fault came about via the jet of the burner being so small that even the smallest debris can find it’s way in and cause a blockage.

The solution? Clean the burner and the jet, before resetting the boiler.

Broken PCB

Being the most important part of the boiler, along with it comes a big cost to fix. PCB’s cost around £4-500 to replace before checking over all other components.

Spark Generator

With the F.28 fault code being related to ignition problems a good part to check would naturally be the spark generator. If this isn’t working properly, logically a flame won’t be produced.

When this happens, the boiler’s survival instincts so to speak kick in and that’s when the boiler begins to lock out after several attempts to ignite.

How Do You Stop This From Happening In The First Place?

An annual boiler service stops these issues from occurring in the first place with each service delivering a guarantee for the next 12 months. Being carried out by a Gas Safe Registered Engineer, the quality stamp will become increasingly evident as time goes on.

Head Over to our Boiler Service page to out more give us a call today.

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