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The NK300S is a (re)filling combination valve that contains an integrated pressure reducing valve, strainer, double check backflow preventer with air vent (to protect potable water supply against back flow of heating water into supply pipe), two shut-off ball valves, pressure gauge, and conveniently located test ports for easy inspections and check out. All the needed devices for refilling a heating system are contained.

Product Features
  • Optimal protection of the potable water supply system
  • Pressure reducing valve with inlet pressure balancing - inlet pressure fluctuation does not influence the outlet pressure
  • Outlet pressure adjustable and directly visible on the pressure gauge
  • Low maintenance effort - cartridge insert and valve insert are completely replaceable
Product Specifications
  • Application: Blanking plug with O-ring
  • Includes: O-ring
  • Used With: NK300S-100, NK300S-100UP
  • Comments: 5 piece set
  • Item Type: Replacement Part
  • Connection Type: NPT
  • Pipe Size (inch)1/2 in. to 2 in.
  • Controlled Fluid: Water
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