BoilerBuddy · Glow-worm guide
Glow-worm boiler fault codes and symptoms
BoilerBuddy helps you diagnose boiler problems, work through minor checks, and escalate major problems to a Gas Safe engineer. Start with the exact code and range shown on your appliance; meanings can differ between models.
From the fault-code directory
Common Glow-worm codes and symptoms
These examples link to existing records for their specific boiler ranges. Open the matching record for its full context and guidance.
Energy
Code F.22: F.22
Safety switch-off: low water pressure in the boiler.
Energy
Code F.28: F.28
The boiler was unable to ignite successfully when starting.
Energy
Code F.29: F.29
The flame has been lost.
Energy
Code F.20: F.20
Safety switch-off: the overheating temperature has been reached.