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The Barnes & Jones “Big Mouth” vent is a thermostatic main vent designed for maximum evacuation of air and non-condensable gases from low- pressure steam systems. Available in 3/4" NPT (standard) and 1/2" NPT (special order). Recommended install at 8"-10" above the steam piping and 12" from the end of the steam main. Cross-over traps installed in the horizontal position

  • Large Air Venting Capability
  • Factory Calibrated & Tested
  • Bronze Body, Forged Brass Cover, Union Nut & Tailpiece
  • Piping Pattern: Vertical (Air Vent) or Horizontal for (Crossover Trap) application

  • 3/4" NPT Threads
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Thread Size:
3/4" NPT
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