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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
146
of
157
TABLE 9-1: Boiler Troubleshooting Procedures
Fault
Probable Causes
Corrective Action
AIRFLOW
FAULT
DURING
IGNITION
1.
Blower stopped running due to
thermal or current overload.
1.
Check combustion blower for signs of
excessive heat or high current drain that may
trip thermal or current overload devices.
2.
Blocked Blower inlet or inlet
air filter.
2.
Inspect the inlet to the combustion blower
including the air filter at the air/fuel valve for
signs of blockage.
3.
Blockage in Blower Proof
switch.
3.
Remove the Blower Proof switch and inspect
for signs of blockage, clean or replace as
necessary.
4.
Blockage in Blocked Inlet
switch.
4.
Remove the Blocked Inlet switch and inspect
for signs of blockage, clean or replace as
necessary.
5.
Defective Blower Proof switch.
5.
Check the continuity of the Blower Proof
switch with the combustion blower running. If
there is an erratic resistance reading or the
resistance reading is greater than zero ohms,
replace the switch.
6.
Defective Blocked Inlet switch.
6.
Turn off unit and check the continuity of the
Blocked Inlet switch. If there is an erratic
resistance reading or the resistance reading is
greater than zero ohms, replace the switch.
7.
Bad inlet air temperature
sensor.
7.
Check the actual inlet air temperature reading
and measure resistance at the Sensor
Harness connection P1. Verify that the
reading conforms to the values shown in
Section 2 of the
Benchmark 750-6000 with
Edge [i]: Reference Manual (OMM-0146, GF-
219).
8.
Defective temperature
sensor.
8.
Refer to CORRECTIVE ACTION 7 and verify
that the voltage conforms to the values shown
in Section 2 of the
Benchmark 750-6000 with
Edge [i]: Reference Manual (OMM-0146, GF-
219).
9.
Loose wire connection
between the Blower and the
Controller.
9.
Check wire connection from the Blower motor
to the Secondary Power Panel.
10.
Defective Air-Fuel Valve
potentiometer.
10.
Check Air/Fuel Valve position at 0%, 50%
and 100% open positions. The positions on
the
Valve Position
bargraph should match
the readings on the Air/Fuel Valve dial.
11.
Hard light.
11.
Check igniter-injector for soot or erosion of
electrode. Check injector solenoid valve to
insure proper open/close operation.