OMM-0153_E
• 5/11/2023 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 104 of 124
CENTURION Installation, Operation & Maintenance Manual
SECTION 10: TROUBLESHOOTING
Centurion Troubleshooting Procedures
Fault
Probable Causes
Corrective Action
2.
Incorrect power supply
transformer wiring.
2.
Check transformer wiring, in AC Power Box, against
the power box transformer wiring diagram to
ensure it is wired correctly.
LOW GAS
PRESSURE
1.
Incorrect supply gas
pressure.
1.
Measure gas pressure upstream of the SSOV
Actuator(s) with the unit firing. Ensure it is above
4.0” W.C.
(995 Pa)
for FM gas train and 4.5”
W.C.
(1,112 Pa) for DBB gas train at full fire.
2.
Defective Low Gas Pressure
switch.
2.
Measure pressure at Low Gas Pressure switch. If
greater than 1 inch above Low Gas Pressure switch
setting, measure continuity across the switch and
replace if necessary.
LOW WATER
LEVEL
1.
Insufficient water level in
system.
1.
Check system for sufficient water level.
2.
Defective water level
circuitry.
2.
Test water level circuitry using the Low Water TEST
and RESET buttons on the Controller’s front panel.
Replace water level circuitry if it does not respond.
3.
Defective water level probe.
3.
Check continuity of probe end to the shell, change
probe if there is no continuity.
MODBUS
COMMFAULT
Unit not seeing information
from Modbus network.
Check network connections. If fault persists, contact
qualified Service Personnel.
PRG SWITCH
CLOSED
DURING
IGNITION
1.
A/F Valve rotated open to
purge and did not rotate to
ignition position.
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 Edge Controller. Refer fault to
qualified service personnel.
2.
Defective or shorted switch.
2.
If the Air/Fuel Valve does rotate to the ignition
position, check the purge switch for continuity
between the N.O. and COM terminals. If the switch
shows continuity when not in contact with the cam,
check to ensure that the switch is wired correctly
(correct wire numbers on the normally open
terminals).
3.
Switch wired incorrectly.
3.
If the switch is wired correctly, replace the switch.
4.
Defective Power Supply
Board or fuse.
4.
Check DS1 & DS2 LEDs on Power Supply Board. If
they are not steady ON, replace Power Supply
Board.
5.
Defective IGST Board.
5.
Check “Heartbeat” LED DS1 and verify it is blinking
ON & OFF every second. If not, replace IGST Board.
PRG SWITCH
OPEN DURING
PURGE
1.
Defective Purge switch.
1.
If the air-fuel valve does rotate, check Purge switch
for continuity when closing. Replace switch if
continuity does not exist.
