Page 77 - NG-1 1150, NG-1 1500, NG-1 2000, NG-1 3000 - Stand-Alone Nitrogen Generator System Installation Manual
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Safety Warning
All troubleshooting is to be performed by qualified personnel. Prior to any system troubleshooting on the nitrogen generation system, ensure that the nitrogen generator is isolated from the compressed air supply and all system risers. Be aware of pressurized system components as some of the troubleshooting procedures require system components to be pressurized. Failure to do so can result in system damage and/or personal injury.
   Nitrogen generator not running
Nitrogen generator not running
Nitrogen not flowing in sprinkler system
Nitrogen generator is short cycling
Air compressor is short cycling
Nitrogen generator running continuously or running more than 4 hours
No lights or indicators on generator
Generator lights and indicators on
Verify nitrogen generator is not in by-pass mode
While the nitrogen generator running, use a gas analyzer to measure the nitrogen output quality. (See Commissioning / Maintenance Section)
While the nitrogen generator running, measure generator production flow rate through flow meter. (See Commissioning / Maintenance Section)
Pressure on generator digital display decreases after generator shuts off with sprinkler system AMD open.
Air compressor short cycles with the nitrogen generator in the standby mode
Generator in nitrogen generation mode with AMD open and unable to pressurize sprinkler system.
Check incoming power and fuses in nitrogen generator
The nitrogen generator may be in the depressurizing phase of the breathing cycle. When sprinkler system reaches the generator cut-in pressure, the nitrogen generator will automatically turn on. (normal operation)
Place nitrogen generator in nitrogen generation mode.
If the nitrogen reading is below 97%, contact Johnson Controls.
Compare generator production rate to system commissioning documentation and/or factory test report. If significantly lower, contact Johnson Controls.
Close inlet to sprinkler system AMD, if pressure continues to decrease, check for leaks in generator cabinet and supply line.
Check supply line from air compressor to nitrogen generator for leaks.
Close AMD. If system supply line pressurizes, check sprinkler system for leaks or inoperable AMD (AMD not automatically closing).
   Check status of solenoids/angle seat valves in generator.
o Solenoids should be energized (LED on) when running
o Angle Seat Valve should be energized (center pin out) when
Check system pressure:
o If system pressure above cut-in pressure of generator, reduce
system pressure below cut-in pressure and check generator
o If system pressure below cut-in pressure of generator, check
power to air compressor.
                  With AMD closed, the pressure on generator digital display remains constant after generator shuts off.
  • AMD partially opening allowing minimal nitrogen flow to sprinkler system results in generator short cycling. Adjust, repair or replace AMD as necessary.
• Verify the AMD pressure is 3-5 psig (.2-.3 bar) above nitrogen generator cut-in pressure. Adjust as necessary
• Adjust the Short Cycling Prevention Regulator
       Nitrogen generator remains on while air compressor short cycles
  • Verifytheexcessairregulatorpressureisset5-10psig(.3-.7)below air compressor cutout pressure. Adjust as necessary. Air compressor should continue to operate until nitrogen generator shuts off. (See Commissioning / Maintenance Section)
• Verify production flow rate and nitrogen purity levels
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