Determination of coil defrosting loads. Part 3: Testing procedures and data reduction
- Kuwait Univ., Safat (Kuwait). Dept. of Mechanical Engineering
- Univ. of Florida, Gainesville, FL (United States). Dept. of Mechanical Engineering
- ZEXEL USA Corp., Decatur, IL (United States)
This is the third part of a five-part paper reporting on work performed under ASHRAE RP-622, ``A Study to Determine Heat Loads Due to Coil Defrosting.`` The objective of the research program on which this paper partly reports was to obtain quantitative and reliable data on the heat loads associated with defrosting a freezer coil of a frequently used design that employs the hot-gas refrigerant method. It was intended that tests be conducted under conditions that are representative of true-to-life operating conditions of freezers in the field. In this paper of the paper, a detailed description of the testing procedures and the data-reduction methodologies used to determine the heat loads due to coil hot-gas defrosting is provided. The discussion of the testing procedures includes the initial positions of the system valves before starting the system, the start-up operating sequence to set the psychrometric freezer room to the desired testing conditions, the operating procedures of a complete refrigeration/hot-gas defrost cycle, and the shutdown operating sequence. The data-reduction section will explain in detail the methodologies used in calculating the total refrigeration load rate, the average load sensible heat ratio, the defrost heat input, the defrost efficiency, and some other important parameters that lead to the determination of the heat loads due to coil hot-gas defrosting. These calculations are performed for the refrigeration and hot-gas defrosting modes of the test fan-coil unit (FCU-T).
- Sponsoring Organization:
- American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, GA (United States); Florida Univ., Gainesville, FL (United States)
- OSTI ID:
- 653202
- Report Number(s):
- CONF-980123--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Determination of coil defrosting loads. Part 1: Experimental facility description
Determination of coil-defrosting loads. Part 4: Refrigeration/defrost cycle dynamics