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Benchmark 750-3000 Boiler Operation, Service, Maintenance Guide - KOREA
SECTION 5 – TROUBLESHOOTING GUIDE
Page
64
of
144
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
OMM-0128_0B
07/17/2017
Ph.: 800-526-0288
TABLE 5-1: Boiler Troubleshooting Procedures
Fault
Indication
Probable Causes
Corrective Action
IGN SWTCH
CLOSED
DURING
PURGE
1.
Air/Fuel Valve not rotating.
2.
Defective or shorted switch.
3.
Switch wired incorrectly.
4.
Defective Power Supply Board or fuse.
5.
Defective IGST Board.
1.
Start the unit. The Air/Fuel Valve should rotate to the purge (open)
position. If the valve does not rotate at all or does not rotate fully
open, check the Air/Fuel Valve calibration. If calibration is okay, the
problem may be in the Air-Fuel Valve or the C-More Controller.
Refer to qualified service personnel.
2.
If the Air/Fuel Valve does rotate to purge, check the ignition switch
for continuity between the N.O. and COM terminals. If the switch
shows continuity when not in contact with the cam replace the
switch.
3.
Check to ensure that the switch is wired correctly (correct wire
numbers on the normally open terminals). If the switch is wired
correctly, replace the switch.
4.
Check DS1 & DS2 LEDs on Power Supply Board. If they are not
steady ON, replace Power Supply Board.
5.
Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF
every second. If not, replace IGST Board.
IGN SWTCH
OPEN
DURING
IGNITION
1.
Air/Fuel Valve not rotating to ignition position.
2.
Defective Ignition switch.
3.
Defective Power Supply Board or fuse.
4.
Defective IGST Board.
1.
Start the unit. The Air/Fuel Valve should rotate to the purge (open)
position, then back to ignition position (towards closed) during the
ignition cycle. If the valve does not rotate back to the ignition
position, check the Air/Fuel Valve calibration. If calibration is okay,
the problem may be in the Air/Fuel Valve or the C-More Controller.
Refer fault to qualified service personnel.
2.
If the Air/Fuel Valve does rotate to the ignition position, check the
ignition position switch for continuity between the N.O. and COM
terminals when in contact with the cam.
3.
Check DS1 & DS2 LEDs on Power Supply Board. If they are not
steady ON, replace Power Supply Board.
4.
Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF
every second. If not, replace IGST Board.