True Advanced Purge (TAP)


The UNITED Fire Systems True Advanced Purge System Model TAP-G3 is designed to automatically purge air from within a dry-pipe or preaction sprinkler system and replace the air with 98% nitrogen from a NITROGEN-PAC™ sprinkler corrosion inhibiting system. The system also automatically samples, analyzes, and displays the percentage of nitrogen within the pipe.


  • Automatic initial purge sequence for removal of air from sprinkler system piping and replacement with 98% nitrogen.
  • Automatic sampling of gas from inside the pipe and permanent display of nitrogen concentration.
  • Easy to read front panel display of nitrogen concentration, purge status, time, and date.
  • Mounts separately from associated purge vent assembly and connects with plenum-rated tubing.
  • Advanced, self-calibrating gas sensing technology with long sensor life.
  • Relay output for system fault remote notification including low nitrogen concentration after automatic initial purge sequence.


  • Eliminates manual operation of ball valves to regulate purging.
  • Eliminates manual use of hand-held nitrogen analyzer to measure nitrogen concentration in the pipe.
  • Read nitrogen value at eye level – no need to climb up to purge vent locations.
  • Unit requires no periodic calibration.
  • Local and remote signaling of fault conditions.
  • Automatic purge sequencing minimizes compressor run time, lengthening compressor life and reducing energy consumption cost.

Data Sheets


Commissioning & Maintenance Checklists

Warranty Information

Contact Our Team

You're looking for expertise and quality. That's where we come in.

Did You Know?
  • Your wet-pipe sprinkler system may not be as filled with water as you expect it to be. A bubble of air may migrate to the highest point in the system, creating a very vulnerable location for internal pipe corrosion. That’s why NFPA 13 now requires that all new wet sprinkler systems be fitted with an air vent at the system’s highest point. This is a good investment for both new and existing systems. The UNITED Fire Systems Model AR-1 automatic air release device is Factory Mutual (FM) Approved for just this function. See here for more information, and take action to prevent damaging corrosion.