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Home Owners Section

Does your Dx system short-cycle due to the over-sizing, which may have been necessary for peak capacity (or future use) requirements? Do you want to provide dehumidification (moisture removal) without the high cost of re-heating?

The Rawal Unloader is a unique (and Patented) refrigeration component that provides modulating unloading capability to non-unloading Dx (direct refrigeration) systems. The Rawal device is used to allow Dx systems to unload to as much as 50% of the systemís capacity. This reduction is done with a response that mimics a modulating chilled water valve (smooth operation from full capacity to minimum capacity).

Unloading below 50% is not recommended to ensure proper oil circulation around the refrigeration system.

APR Control - Sample Spec - 050923
Basics of the Rawal APR Refrigeration Device
R-22 - Fast Selection Table up to 20 tons - 50404
R-410A - Fast Selection Table up to 20 tons
Rawal Devices Service Manager Application Note - 050908