AERCO BMK 1.5 LN Dual Fuel Feb 2013 - Manual (Page 92)

CHAPTER 8: TROUBLESHOOTING GUIDE
Page 92 of 162 PR2: 05/09/12
Benchmark 1.5LN Dual-Fuel Low NOx Boiler
Operation and Maintenance Manual
OMM-0041_0C
GF-121
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
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).
TABLE 8-1. BOILER TROUBLESHOOTING (Continued)