Centurion Water Heater- Edge [ii]: Install-Operation-Service
SECTION 10: TROUBLESHOOTING
OMM-0153_A
• 8/25/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 108 of 131
Centurion Troubleshooting Procedures
Fault
Probable Causes
Corrective Action
2.
Energy Management System
does not have unit enabled.
2.
If there are two external wires on these terminals
check any Energy Management system to see if they
have the units disabled (a jumper may be
temporarily installed to see if the interlock circuit is
functioning).
3.
Device proving switch
hooked to interlocks is not
closed.
3.
Check that proving switch for any device hooked to
the interlock circuit is closing and that the device is
operational.
LINE
VOLTAGE
OUT OF
PHASE
1.
Line and Neutral switched in
AC Power Box.
1.
Check hot and neutral in AC Power Box to ensure
they are not reversed.
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
COMMFAUL
T
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).
