Tempering Valve Type 21

Hoffman Specialty Tempering Valves are designed to control temperature in water mixing applications such as radiant floor heating and industrial processing. They can also be used to divert flow in cooling systems. Series 21 Valves can be used for residential, industrial, commercial or institutional applications.

Note: This valve should not be used on potable water applications nor should it be used as an anti-scald device.

Features and Benefits

  • Fast acting, corrosion resistant actuator
  • Solid filled thermostatic actuator exerts high operating force and provides reliable service
  • Easy temperature adjustment
  • No special tools required
  • Cast brass body
  • Adjustable temperature ranges
    • Model 21 140–200°F (60–93°C)
    • Model 21H 100–200°F (38–93°C)
    • Model 21LT 100–140°F (38–60°C)
  • Maximum pressure 125 psig (8.6 bar)
  • Maximum hot water supply temperature 235°F (113°C)

Model 21 provides wide temperature adjustment range for hot and cold water mixing in applications other than domestic potable hot water.

Model 21H provides widest temperature adjustment range for radiant heating applications where accurate temperature control is less critical.

Model 21LT provides the greatest accuracy of  temperature control.


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