Hoffman Main Steam Vents

Information:

• Hoffman Specialty General Catalog
• Hoffman Specialty Service Parts Catalog

Model 4A Part No.401413 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)*
• Maximum pressure 10 psig (0.7 bar)

Model 75 Part No. 401434 75H Part No. 401437 Air Valve (non-vacuum)

• Float-type thermostatic vent
• For medium and large systems
• Single non-adjustable port
• 1/2 NPT female and 3/4 NPT male straight shank
• Maximum operating pressure*
  • Model 75 3 psig (0.2 bar)
  • Model 75H 10 psig (0.7 bar)
• Maximum pressure 15 psig (1.0 bar)

Model 76 Part No. 401432 Vacuum Valve

• Float-type themostatic vent
• For medium and large one-pipe vacuum 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 8″ (450mm) above the boiler water line
• Maximum operating pressure 3 psig (0.2 bar)
• Maximum pressure 15 psig (1.0 bar)

Special Steam Vents

Model 3 Part No. 401419 Steam Air Line Valve

• Thermostatic vent (no float)
• For Air Line or Paul Systems
• Inlet 1/8 NPT, outlet 1/4 NPT
• Maximum operating pressure 25 psig (1.7 bar)* to vacuum
• Maximum pressure 25 psig (1.7 bar)

Model 4 Part No. 401416 Quick Valve

• Thermostatic air vent
• For steam systems and process equipment
• Operates on temperature change only; does not close against water
• Must be installed 6-10″ (150-250mm) above horizontal return and 18″ (450mm) above the boiler water line
• 1/2 NPT female and 3/4 NPT male straight shank
• Maximum operating pressure 25 psig (1.7 bar)*
• Maximum pressure 25 psig (1.7 bar)

Model 74 Part No. 401429 Steam Unit Heater Air Valve 

• Float-type thermostatic vent • 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 35 psig (2.4 bar)*
• Maximum pressure 35 psig (2.4 bar)