Rated in accordance with the latest issue of ARI Standard 550/590.
ARI CERTIFICATION PROGRAM
The performance of YORK MAXE chillers is certified to the Air Conditioning and Refrigeration Institute (ARI) complying with the certification sections of the latest issue of ARI Standard 550/590. Under this Certification Program, chillers are regularly tested in strict compli- ance with this Standard. This provides an independent, third-party verification of chiller performance.
YORK YR screw chillers are designed to comply with ASHRAE Standard 90.1-1999 and 90.1-2001. The su- perior part-load performance of the YORK YR chillers far exceeds the IPLV/NPLV requirements of ASHRAE 90.1, providing superior Real World Energy savings for efficiency conscious owners.
COMPUTERIZED PERFORMANCE RATINGS
Each chiller is custom-matched to meet the individual building load and energy requirements. A large num- ber of standard heat exchangers and pass arrange- ments are available to provide the best possible match.
It is not practical to provide tabulated performance for each combination, as the energy requirements at both
full- and part-load vary significantly with each heat ex- changer and pass arrangement. Computerized ratings are available through each YORK sales office. These ratings can be tailored to specific job requirements, and are part of the ARI Certification Program.
OFF-DESIGN PERFORMANCE
Since the vast majority of its operating hours are spent at off-design conditions, a chiller should be chosen not only to meet the full-load design, but also for its ability to perform efficiently at lower loads and lower tower water temperatures. It is not uncommon for chillers with the same full-load kW/TON to have an operating cost difference of over 10% due to part-load operation.
Part-load information can be easily and accurately gen- erated by computer. And because it is so important to an owner’s operating budget, this information is now standard within the ARI Certification Program in the form of an Integrated Part-Load Value (IPLV), and Non- Standard Part-Load Value (NPLV).
The IPLV / NPLV formulas from ARI Standard 550/590 closely track chiller operations, and provide a more ac- curate indication of chiller performance than the previ- ous IPLV / APLV formula. A more detailed analysis must take into account actual building load profiles, and lo- cal weather data. Part-load performance data should be obtained for each job using its own design criteria.
