Benchmark 2500 - 3000 Boilers
CHAPTER 8 – TROUBLESHOOTING GUIDE
OMM-0094_0F
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
109
of
207
GF-137
Ph.: 800-526-0288
09/30/2015
TABLE 8-1: BOILER TROUBLESHOOTING – Continued
FAULT INDICATION
PROBABLE CAUSES
CORRECTIVE ACTION
DELAYED
INTERLOCK OPEN
1.
Delayed Interlock Jumper not
properly installed or missing.
2.
Device proving switch hooked to
interlocks is not closed.
1.
Check to insure jumper is properly installed across the delayed
interlock terminals in the I/O Box.
2.
If there are 2 external wires on these terminals, check to see if
an end switch for a proving device (such as a pump, louver,
etc.) is tied these interlocks. Ensure that the device and/or its
end switch is functional. A jumper may be temporarily installed
to test the interlock.
DIRECT DRIVE
SIGNAL FAULT
1.
Direct drive signal is not present:
--Not yet installed.
--Wrong polarity.
--Signal defective at source.
--Broken or loose wiring.
2.
Signal is not isolated (floating).
3.
Control Box signal type selection
switches not set for correct signal
type (voltage or current).
1.
Check I/O Box to ensure signal is hooked up.
--Hook up if not installed.
--If installed, check polarity.
--Measure signal level.
--Check wiring continuity between source and unit.
2.
Check signal at source to ensure it is isolated.
3.
Check DIP switch on PMC board to ensure it is set correctly for
the type of signal being sent. Check control signal type set in
Configuration
menu.
FLAME LOSS
DURING IGN
1.
Worn Flame Detector.
2.
No spark from Spark Igniter.
3.
Defective Ignition Transformer.
4.
Defective Ignition/Stepper (IGST)
Board.
5.
Defective SSOV.
1.
Remove and inspect the Flame Detector for signs of wear.
Replace if necessary.
2.
Close the internal gas valve in the unit. Install and arc a spark
igniter outside the unit.
3.
If there is no spark, check for 120VAC at the primary side to the
ignition transformer during the ignition cycle.
4.
If 120VAC is not present, the IGST Board in the Control Box
may be defective. Refer fault to qualified service personnel.
5.
While externally arcing the spark igniter, observe the open/close
indicator in the Safety Shut-Off Valve to ensure it is opening. If
the valve does not open, check for 120VAC at the valve input
terminals. If 120VAC is not present, the IGST board in the
Control Box may be defective. Refer fault to qualified service
personnel.