4A, 1/2" x 3/4" Straight Steam Main Air Valve
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Air Valve (non-vacuum)
- Float-type thermostatic vent
- For residential or small one-pipe or two-pipe systems
- Single non-adjustable port
- 1⁄2" NPT female and 3⁄4" NPT male straight shank
- Install 6-10" (150-250mm) above horizontal return and 18" (450mm) above the boiler water line
- Maximum operating pressure 2 psig (0.13 bar)(Drop away pressure - maximum pressure against which the vent can open).
- Maximum pressure 10 psig (0.7 bar)
1/2" x 3/4"
Max Operating Pressure:
Temperature Range (F):
Max Temp (F):
Min Temp (F):
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