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Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 9
– TROUBLESHOOTING
OMM-0145_A99
• GF-218 • 9/18/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
152
of
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TABLE 9-1: Boiler Troubleshooting Procedures
Fault
Probable Causes
Corrective Action
OUT OF
PHASE
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 the value in Table 4-2 (Natural Gas) or
Table 4-5 (Propane).
2.
Defective Low Gas Pressure
switch.
2.
Measure gas pressure at the Low Gas
Pressure switch. If it is
greater than
1 inch
above
the Low Gas Pressure switch setting
in Table 4-2 (Natural Gas) or Table 4-5
(Propane), 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
COMMFAU
LT
Unit not seeing information from
Modbus network.
Check network connections. If fault persists,
contact qualified Service Personnel.
PRG
SWTCH
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 [i] 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.