Smell gas? Leave the property and call the National Gas Emergency line on 0800 111 999
BoilerCodes
F.28
Glow-worm fault code / F1

Glow-worm F.28: ignition unsuccessful when starting up (F1 on older models)

Check these first, then call an engineer

The boiler tried to light and couldn't. Glow-worm says this usually relates to the gas supply, such as a prepayment meter out of credit, or a frozen or blocked condensate pipe.

What you can safely do

  1. Check your gas supply and, if you have a prepayment meter, top it up.
  2. In freezing weather, check the condensate pipe outside and thaw it with warm (not boiling) water.
  3. Press the reset button for one second. Glow-worm's instructions say to consult a competent person if three resets don't clear it.

Call a Gas Safe engineer if

  • The fault is still there after three resets.
  • You smell gas at any point. Leave the property and call 0800 111 999.
Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to: Energy range, Betacom A range. Codes can differ between models, so check your manual.

What F.28 means on each Glow-worm model

From Glow-worm's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

ModelMeaningCauses listed for engineers
Energy rangeIgnition unsuccessful when starting upGas meter defective, air in gas, low gas pressure, ignition parts defective
Betacom A rangeIgnition faultNot listed

Common questions about Glow-worm F.28

What does F1 mean on an older Glow-worm boiler?

Glow-worm says F1 on older appliances relates to the same problems as F.28 and F.29: usually the gas supply or a frozen or blocked condensate pipe.

How many times can I reset a Glow-worm boiler?

Glow-worm's operating instructions say that if you can't clear an ignition fault after three reset attempts, consult a competent person.

Nearby Glow-worm codes

F.22F.29F.75F.23F.72F.20F.25

See all 41 Glow-worm codes

Sources