For modulating liquid level control in refrigeration, freezing and air conditioning plant, a system comprising a modulating servo-controlled main expansion valve type PMFL or PMFH, controlled by a pilot float valve type SV, is used.

PMFL and SV systems are used on the evaporator side. PMFH and SV systems are used on the condenser side. The system is suitable for use with ammonia or fluorinated refrigerants. The PMFL and PMFH can be used in liquid lines to or from:

  • evaporators
  • separators
  • intermediate coolers
  • condensers
  • receivers

Modulating liquid level regulation provides liquid injection that is proportional to the actual capacity. This gives a constant amount of flash gas, thus ensuring stable control and economical operation because variations in pressure and temperature are held to a minimum.


  • Pressure gauge connection to monitor inlet pressure
  • Simple installation
  • Main valve top cover can be located in any position without affecting the function
  • Applicable to HCFC, HFC, and R717 (Ammonia).
  • PMFL/PMFH are based on PM valve family housings
  • Same flange program as for PM valve series
  • Valve housing in low temperature cast iron (spherical) - EN GJS 400-18-LT
  • Manual operation possible Position indicator available

Customer Service

Edward van Doorn