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2912

No flame signal during calibration

Worcester Bosch Greenstar 2000 Combi

Category
V
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 no water collecting in the sump.
▶ Replace the air and/or gas ratio control valve.
▶ Replace the control unit and/or burner control unit.
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