Bosch Greenstar FS Series Installation And Maintenance Instructions For Contractors page 76

Faults
Display Description
EA No flame detected.
GFA: Safety time expired.
F0 Internal fault
F1 Internal data error.
F7 Flame detected even when burner is
off.
FA After switching gas off: Flame is
detected.
Fd Reset button pressed by mistake.
Temperature gradient limiter:
Temperature rise too fast
Table 40 Faults shown on the display
76
Elimination
▶ Check that ground lead is properly connected, replace if defective.
▶ Check that gas cock is open.
▶ Check inlet gas pressure; correct if needed.
▶ Check power supply.
▶ Check electrodes for visual damage; replace if defective.
▶ Check flue gas system; clean or repair if defective.
▶ Check gas/air ratio; correct if out of range.
▶ Check gas valve; replace if defective.
▶ In room air operation, check air supply or ventilation apertures.
▶ Clean the condensate trap.
▶ Remove diaphragm at fan inlet connection and check for contamination or cracks.
▶ Check heat exchanger for soiling ( Section 15.1.615.1.6, page 65).
▶ Check gas cock; replace if defective.
▶ Insert code plug correctly; replace if defective.
▶ Press reset for 3 seconds and release. When the button is released, the appliance will restart.
▶ Check electrical plug-in contacts and ignition leads; replace PCB if defective.
▶ Check gas/air ratio; correct if out of specification.
▶ Reset boiler to the factory default setting ( service function 8.E).
▶ Check electrodes; replace if defective.
▶ Check flue gas system; clean or repair if defective.
▶ Check PCB for moisture; dry if needed.
▶ Check gas cock; replace if defective.
▶ Clean condensate trap.
▶ Check electrodes and leads; replace if defective.
▶ Check flue gas system; clean or repair if needed.
▶ Press reset button again.
▶ Check cable harness to safety high limit and gas cock for ground connection.
▶ Fully open service shut-off valves.
▶ Check electrical connection between heating zone pump and Heatronic.
▶ Check pump plug connection per installation instructions.
▶ Manually test operation of heating zone pump and replace if defective.
▶ Set pump speed correctly to match maximum output.
Greenstar FS/Combi FS – 6 720 810 590 (2020/04)