Watts Aerco Benchmark OMM-0117 Operation And Maintenance Manual page 69

Benchmark 5000-6000 Operation & Maintenance Manual
SECTION 5 – TROUBLESHOOTING GUIDE
TABLE 5-1: Boiler Troubleshooting Procedures
FAULT
INDICATION
See HIGH WATER TEMPERATURE SWITCH
1.
HIGH WATER
OPEN.
TEMPERATURE
Temp HI Limit setting is too low.
2.
1. Communication fault has occurred between
IGN BOARD
the PMC board and Ignition/Stepper (IGST)
COMM FAULT
board.
Air/Fuel Valve not rotating.
1.
Defective or shorted switch.
2.
IGN SWTCH
CLOSED
DURING
PURGE 3. Switch wired incorrectly.
4. Defective Power Supply Board or fuse.
Defective IGST Board.
5.
OMM-0118_B • GF-203 • 5/9/2019
PROBABLE CAUSES
Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
CORRECTIVE ACTION
See HIGH WATER TEMPERATURE SWITCH OPEN.
1.
Check Temp HI Limit setting.
2.
1. Press CLEAR button and restart unit. If fault persists, contact
qualified Service Personnel.
Start the unit. The Air/Fuel Valve should rotate to the purge (open)
1.
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.
If the Air/Fuel Valve does rotate to purge, check the ignition switch
2.
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.
Check "Heartbeat" LED DS1 and verify it is blinking ON & OFF
5.
every second. If not, replace IGST Board.
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