Glow-worm Betacom C Fault codes & diagnostics

2 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 24-30 kW 2010-2015 Discontinued

Replaced by: Betacom 4

This boiler uses indicator light combinations

Note which lights are on, off, or flashing and at what speed. Match the combination to the cards below. Do not reset until you have noted the pattern. How to read fault codes →

Fault codes

All 2 documented codes

Tap any card for details

Boiler lockout indicator ON

Your boiler has shut itself down for safety reasons and needs to be manually restarted to resume heating and hot water.

High DIY-safe £0-180

What to check first

  1. Turn the left-hand control knob to the 'Reset' position
  2. Wait for approximately one minute to allow the system to cool down
  3. Turn the knob back to your desired temperature setting

Parts commonly replaced

  • Overheat thermostat
  • Ignition electrode
  • PCB
Full explanation for Boiler lockout indicator ON
Burner indicator Flashing

Your boiler has detected a simple operating error that usually means a control knob is in the wrong position or the system needs a basic restart.

Medium DIY-safe £0-80

What to check first

  1. Check that the Hot Water control knob is set to a normal temperature position
  2. Turn the left-hand control knob to the 'Reset' position
  3. Hold it for a few seconds, then turn it back to your desired setting

Parts commonly replaced

  • None (usually a settings issue)
  • Control Knob
Full explanation for Burner indicator Flashing