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Development and Verification of a Linear-Fit Mixed System Rating Method for Unitary Two-Speed and Variable-Speed Air Conditioners

Published

Author(s)

William V. Payne

Abstract

A linear-fit method of rating residential-type air conditioning systems was evaluated based on performance predictions and laboratory testing of one two-speed matched system and two mixed systems (matched two-speed condensing unit, matched indoor coil blower, and two mixed coil blowers). The individual evaporators and the condensing unit were separately tested using water heated/cooled condensing/evaporating units at standard air conditions over a range of evaporator refrigerant saturation temperatures, evaporator superheats, and liquid refrigerant temperatures. Capacity predictions were within ±1.0 % of the tested values for the mixed systems, and the EER predictions were within ±1.5 % of the measured EERs. The methods used for system rating on the two-speed system can also be applied to a variable-speed system.
Citation
Technical Note (NIST TN) - 1667
Report Number
1667

Keywords

air conditioner, cooling capacity, mixed system, rating procedure, SEER, two-speed system, variable-speed system

Citation

Payne, W. (2010), Development and Verification of a Linear-Fit Mixed System Rating Method for Unitary Two-Speed and Variable-Speed Air Conditioners, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.TN.1667 (Accessed March 19, 2024)
Created June 7, 2010, Updated November 10, 2018