AN EXPERIMENTAL ANALYSIS OF THE EFFECT OF REFRIGERANT CHARGE LEVEL AND OUTDOOR CONDITION ON A WINDOW AIR CONDITIONER

Abstract

R22 is an hydrochlorofluorocarbon widely used in refrigerant and air conditioning plants and although it has a low ozone depletion potential (0.05), it is necessary to consider the large amount that commonly escapes from commercial units to the atmosphere. This paper presents experimental investigation on the performance of a window air conditioner operated with R22 and the M20 (80% R407C and 20% HC blend by wt.) refrigerant mixture tested under different refrigerant charge levels and outdoor conditions. Experiments were conducted in accordance with the Bureau of Indian standards procedure in a psychrometric test facility. Capillary and charge optimization tests were conducted for the both R22 and the M20 refrigerant mixture based on maximum coefficient of performance. Refrigerant charge in the air conditioner was systematically varied and the influences of refrigerant charge quantities and outdoor conditions on system performance are studied for both R22 and the M20 refrigerant mixture. At each charge levels, the outdoor room conditions were changed in accordance with Bureau of Indian standards. It is observed that R22 is more sensitive to deviations in charge levels as compared to the M20 refrigerant mixture. A decrease in charge level of about 7% reduced the system refrigerating capacity by 11.3% with R22 while with the M20 refrigerant mixture it reduces by 6.9% only. Similarly an over charge by 7% reduces the refrigerating capacity of the system by 13.8% with R22 while with M20 it reduces by 6.5% only.

Keywords

Dates

  • Submission Date2009-08-01
  • Revision Date2009-12-06
  • Acceptance Date2009-12-22

DOI Reference

10.2298/TSCI10041121R

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