BoilerTool
Home / Greenstar 4000 (before May 2021) / 2948
2948

No flame signal with low output

Worcester Bosch Greenstar 4000 (before May 2021)

Category
B
Remedy
Burner starts automatically after purging. This can be caused by strong winds.
If this fault occurs frequently:
▶ Check CO2 settings.
▶ Check flue outlet position for effects of excessive wind pressure.
▶ Check flue integrity.
This code also applies to:
© 2026 BoilerTool