The Variable speed drive (VSD) models of the APS Semi hermetic Acpac range include a fully programmed Vacon VSD to adjust the compressor speed to maintain the desired evaporating pressure.

In extreme ambient temperatures the VSD models will act to ensure the compressor stays inside it’s operating envelope, this is called the High Limit Pressure Safety (HLPS) feature and will allow the compressor to provide the maximum amount of cooling capacity at high ambient conditions. The APS VSD models are quick and easy to install and commission and are suitable for either R134a or R404A refrigerants.

These models are well suited for refrigerated reach-in and walk-in cool rooms and freezers for every product imaginable including butcher shops, fish shops, fruit and vegetable stores, fast food chains, food processors and many more.


  • Vacon VSD adjusts compressor speed to match the refrigeration load required.
  • Comes pre-programmed for trouble free operation and fast commissioning.
  • Ensures the compressor operates below its maximum operating current.
  • Contactor and Overload no longer required as power goes direct to VSD.
  • Electronic Oil Regulator installed to ensure oil return is always maintained.

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