Aerco BENCHMARK 2500DF User Manual page 105

Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
FAULT INDICATION
Blower stopped running due to thermal
1.
AIRFLOW FAULT
or current overload.
DURING IGNITION
Blocked Blower inlet or inlet air filter.
2.
Blockage in Blower Proof switch.
3.
Blockage in Blocked Inlet switch.
4.
Defective Blower Proof switch.
5.
Defective Blocked Inlet switch.
6.
Loose temperature to AUX connection in
7.
I/O Box.
8.
9.
10.
11.
12.
13.
OMM-0099_0A
GF-145
CHAPTER 8 – TROUBLESHOOTING GUIDE
TABLE 8-1: BOILER TROUBLESHOOTING
PROBABLE CAUSES
Defective temperature sensor.
Loose wire connection between the 0-
10V signal from I/O box to the Blower
input.
Defective I/O Box.
Wrong 0-10V output selection on the
control box.
Defective Air-Fuel Valve potentiometer.
Hard light.
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Check combustion blower for signs of excessive heat or high
1.
current drain that may trip thermal or current overload devices.
Inspect the inlet to the combustion blower including the air filter at
2.
the air/fuel valve for signs of blockage.
Remove the Blower Proof switch and inspect for signs of
3.
blockage, clean or replace as necessary.
Remove the Blocked Inlet switch and inspect for signs of
4.
blockage, clean or replace as necessary.
Check the continuity of the Blower Proof switch with the
5.
combustion blower running. If there is an erratic resistance
reading or the resistance reading is greater than zero ohms,
replace the switch.
Turn off unit and check the continuity of the Blocked Inlet switch.
6.
If there is an erratic resistance reading or the resistance reading
is greater than zero ohms, replace the switch.
Check the actual inlet air temperature and measure voltage at
7.
AUX input in the I/O Box. Verify that the voltage conforms to the
values shown in the tabular listing provided in Appendix C.
Refer to CORRECTIVE ACTION 7 and verify that the voltage
8.
conforms to the values shown in Appendix C.
Check wire connection from I/O Box 0-10V signal to the Blower
9.
Motor.
Measure voltage at the I/O box 0-10V output. A voltage of 8.2V
10.
equates to a 100% open valve position.
Check the Analog Out option on the C-More Configuration
11.
Menu. Valve Position 0-10V should be selected.
Check Air/Fuel Valve position at 0%, 50% and 100% open
12.
positions. The positions on the VALVE POSITION bargraph
should match the readings on the Air/Fuel Valve dial.
Check igniter-injector for soot or erosion of electrode. Check
13.
injector solenoid valve to insure proper open/close operation.
Ph.: 800-526-0288
CORRECTIVE ACTION
Page 105 of 234
PR1: 05/21/2014