Fault Detection and Diagnostics for Commercial Coolers and Freezers

Abstract

Most of the previous diagnostics research for vapor-compression equipment has been performed for packaged air conditioners and chillers. This paper describes application of a decoupling-based diagnostic technique that was originally developed for air conditioners to equipment used in walk-in coolers and freezers. Testing was performed on a small, restaurant-style walk-in cooler and a small walk-in freezer for faulted and unfaulted conditions. The data was then used to characterize how the fault features respond to faults and to evaluate the performance of the decoupling-based diagnostic technique.