period one
Types of Water Chillers
notes
Equipment Rating Standards
▲Air-Conditioning & Refrigeration Institute (ARI)
◆Standard 550/590–1998: centrifugal and helical-rotary water chillers
◆Standard 560–1992: absorption water chillers
Figure 21
Equipment Rating Standards
The Air-Conditioning & Refrigeration Institute (ARI) establishes rating standards for packaged HVAC equipment. ARI also certifies and labels equipment through programs that involve random testing of a manufacturer’s equipment to verify published performance. These equipment rating standards have been developed to aid engineers in comparing similar equipment from different manufacturers. Chiller full-load efficiency is described in terms of kW/ton and coefficient of performance (COP). Additionally, two efficiency values developed by ARI that are receiving increased attention are the Integrated Part-Load Value (IPLV) and Non-StandardPart-Load Value (NPLV).
ARI’s part-load efficiency rating system establishes a single number to estimate both the full- and part-load performance of a stand-alone chiller. As part of ARI Standard 550/590–1998, Water-Chilling Packages Using the Vapor-Compression Refrigeration Cycle, and ARI Standard 560–1992, Absorption Water Chilling- Heating Packages, chiller manufacturers may now certify their chiller part-load performance using the IPLV and NPLV methods. This gives the engineering community an easy and certified method to evaluate individual chillers. Understanding the scope and application limits of IPLV and NPLV is, however, crucial to their validity as system performance indicators.
