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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
155
of
157
TABLE 9-1: Boiler Troubleshooting Procedures
Fault
Probable Causes
Corrective Action
4.
Incorrectly wired switch.
4.
Ensure that the SSOV Proof of Closure switch
is correctly wired.
STEPPER
MOTOR
FAILURE
1.
Air/Fuel Valve unplugged.
1.
Check that the Air/Fuel Valve is connected to
the Edge [i] Controller.
2.
Loose wiring connection to the
stepper motor.
2.
Inspect for loose connections between the
Air/Fuel Valve motor and the wiring harness.
3.
Defective Air/Fuel Valve
stepper motor.
3.
Replace stepper motor.
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.
6.
Air/Fuel Valve out of
calibration
6.
Perform the stepper motor calibration
procedure (
Main Menu
→
Diagnostics
→
Subsystems
→
Air Fuel Valve Stepper Motor
)
.
9.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES
Refer to Table 9-2 to troubleshoot faults which may occur without a specific fault message being
displayed.
TABLE 9-2: Boiler Troubleshooting with No Fault Message Displayed
Observed
Incident
Probable Causes
Corrective Action
Hard Light-
Off
1.
Clogged/damaged Gas
Injector on Igniter-Injector
(Figure 8-1a through Figure 8-
1c).
1.
Disconnect the Staged Ignition Assembly
solenoid from the Gas injector Tube of the
Igniter-Injector (Figure 8-1a through Figure 8-
1c) and inspect Gas Injector to ensure it is not
clogged or damaged.
2.
Defective Staged Ignition
Solenoid (Figure 8-1a through
Figure 8-1c).
2.
Close the Manual Shutoff Valve. Attempt to
start the unit and listen for a “clicking” sound
that the Staged Ignition Solenoid makes
during Ignition Trial. If “clicking” sound is not
heard after 2 or 3 attempts, replace the
Staged Ignition Solenoid.
Fluctuating
Gas
Pressure
1.
Gas pressure going into unit is
fluctuating.
1.
Stabilize gas pressure going into unit. If
necessary, troubleshoot Building Supply
Regulator.
2.
Damping Orifice not installed.
2.
Check if the gas train is supposed to have a
Damping Orifice, and if so, ensure that it is
installed in the SSOV Actuator, as shown in
Figure 10-1, below. For DBB Gas Trains, the
Damping Orifice is installed in the