228
Flame signal without flame present
Worcester Bosch Greenstar 4000 (from May 2021)
Remedy
Tip: Check the ceramic insulator is not damaged, this can cause the spark to earth, twist and pull the ceramic insulator to ensure it is not broken.
▶ Check the flame sense and the lead and replace if required.
▶ Check the earth tags on the boiler and on the electrodes.
▶ Check the operation of the siphon and that no water is collecting in the sump.
▶ Replace the gas valve.
▶ Replace the control unit and/or burner control unit.
This code also applies to: