Table of Contents
Advertisement
Benchmark 2.0LN Dual-Fuel Low NOx Boiler
GF-127
OMM-0052_0E
FAULT INDICATION
STEPPER MOTOR
FAILURE
(continued)
8.2
ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES
Refer to Table 8-2 to troubleshoot faults which may occur without a specific fault message being displayed.
TABLE 8-2. BOILER TROUBLESHOOTING WITH NO FAULT MESSAGE DISPLAYED
OBSERVED INCIDENT
1. Staged Ignition Ball Valve closed.
2. Clogged/damaged Gas Injector
3. Defective Staged Ignition Solenoid
Hard Light-Off
1. Gas pressure going into unit is
2. Damping Orifice not installed.
Fluctuating Gas Pressure
1. IGST and Power Supply Boards in
Air/Fuel Valve "hunting" at
the 80% Valve Position
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
PR2: 04/22/13
Operation and Maintenance Manual
TABLE 8-1. BOILER TROUBLESHOOTING (Continued)
PROBABLE CAUSES
2. Air/Fuel Valve unplugged.
3. Loose
wiring connection
stepper motor.
4. Defective
Air/Fuel
Valve
motor.
5. Defective Power Supply Board or
fuse
6. Defective IGST Board
PROBABLE CAUSES
(Figure 8-2).
(Figure 8-2).
fluctuating.
Control Box are outdated.
CORRECTIVE ACTION
2. Check that the Air/Fuel Valve is connected to the Control Box.
to the
3. .Inspect for loose connections between the Air/Fuel Valve motor
and the wiring harness.
stepper
4. Replace stepper motor.
5. Check DS1 & DS2 LEDs on Power Supply Board. If they are not
steady ON, replace Power Supply Board.
6. Check "Heartbeat" LED DS1 and verify it is blinking ON & OFF
every second. If not, replace IGST Board.
CORRECTIVE ACTION
1. Open the 1/4" Ball Valve downstream of the SSOV (Fig. 8-1).
2. Remove and inspect Gas Injector to ensure it is not clogged or
damaged.
3. Close the 2" and the 1/4" Ball Valve downstream of the SSOV (Fig. 8-
1). 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.
1. Stabilize gas pressure going into unit. If necessary, troubleshoot
Building Supply Regulator.
2. Check to ensure that the Damping Orifice is installed in the SSOV
Actuator shown in Figure 8-3. (For IRI Gas Trains, the Damping Orifice
is installed in the downstream SSOV Actuator).
1. Check to ensure that the IGST and Power Supply Boards are Rev. E
or higher.
Page 93 of 158
CHAPTER 8: TROUBLESHOOTING GUIDE
Advertisement
Table of Contents
