AERCO BMK 1.5 LN October 2012 - Manual (Page 94)

Page 94 of 166 PR1:10/18/12 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
CHAPTER 8
TROUBLESHOOTING
GF-120
OMM-0041 0E
Benchmark 1.5LN Low NOx Boiler
Installation, Operation and Maintenance Manual
TABLE 8-1. BOILER TROUBLESHOOTING (Continued)
FAULT
INDICATION
PROBABLE CAUSES CORRECTIVE ACTION
DELAYED
INTERLOCK OPEN
1. Delayed Interlock Jumper not installed or
removed.
2. Device proving switch hooked to
interlocks is not closed
1. Check for a jumper 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 device such as a pump, louver, etc. is tied these
interlocks. Ensure that the device and or its end switch are
functional. (jumper may be temporarily installed to test 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 continuity of wiring between source and boiler.
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. Burner Ground Screw not installed or
loose.
2. Worn flame detector
3. No spark from Spark Plug
4. Defective Ignition Transformer
5. Defective Ignition/Stepper (IGST) Board
6. Defective SSOV
7. RSI Regulator not properly adjusted.
8. Closed RSI Gas Valve in RSI line.
1. Inspect and install/retighten Burner Ground Screw.
2. Remove and inspect the flame detector for signs of wear. Replace
if necessary.
3. Close the internal gas valve in the boiler. Install and arc a spark
ignitor outside the unit.
4. If there is no spark, check for 120VAC at the primary side to the
ignition transformer during the ignition cycle.
5. If 120VAC is not present, the IGST Board in the Control Box may
be defective. Refer fault to qualified service personnel.
6. While externally arcing the spark ignitor, 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 valves input
terminals. If 120VAC is not present, the IGST board in the Control
Box may be defective. Refer fault to qualified service personnel.
7. Refer to Chapter 7, paragraph 7.4 and check the RSI Regulator
calibration. The RSI regulator output should be between 3.0” W.C.
and 5.0” W.C.
8. Check position of RSI Gas Valve (Figure 8-1).