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Benchmark 750-3000 Boiler Operation, Service, Maintenance Guide - KOREA
SECTION 5 – TROUBLESHOOTING GUIDE
OMM-0128_0A
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
67
of
144
GF-206-K
Ph.: 800-526-0288
07/17/2017
TABLE 5-1: Boiler Troubleshooting Procedures
Fault
Indication
Probable Causes
Corrective Action
O2 % OUT OF
RANGE
1.
Combustion Calibration incorrect.
2.
Blocked inlet air duct or louver.
1.
Check Combustion Analyzer and recalibrate the boiler.
2.
Unblock air inlet and measure open area for combustion air to the
room.
RECIRC PUMP
FAILURE
1.
Internal recirculation pump failed.
1. Replace recirculation pump.
REMOTE
SETPT
SIGNAL FAULT
1.
Remote setpoint signal not present:
Not yet installed.
Wrong polarity.
Signal defective at source.
Broken or loose wiring.
2.
Signal is not isolated (floating) if 4 to 20 mA.
3.
C-More Controller 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 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 item 6 of the
Configuration
menu (see Section 2.6:
Configuration Menu
).
RESIDUAL
FLAME
1.
Defective Flame Detector.
2.
SSOV not fully closed.
1.
Replace Flame Detector.
2.
Check open/close indicator window of Safety Shut-Off Valve (SSOV)
and ensure that the SSOV is fully closed. If not fully closed, replace the
valve and or actuator.
Close the Gas Shut-Off Valve downstream of SSOV (see Section 1,
Figure 1-1). Install a manometer or gauge at the leak detection port
between the SSOV and Gas Shut Off Valve. If a gas pressure reading
is observed replace the SSOV Valve and/or Actuator.
SSOV FAULT
DURING
PURGE
See SSOV SWITCH OPEN
SSOV FAULT
DURING RUN
SSOV switch closed for 15 seconds during run.
1.
Replace or adjust micro-switch in SSOV actuator. If fault persists,
replace actuator.