Title: HOW TO MAKE AND USE A HOMEMADE, LARGE-VOLUME, EFFICIENT SHELTER-VENTILATING PUMP: THE KEARNY AIR PUMP.
Abstract: after system start-up, decreased with time because of frost accumulation on the outdoor heat exchanger but increased with increasing ambient relative humidity. At ambient temperatures less than 4.4/sup 0/C (40/sup 0/F), the COP and capacity degradations caused by frost formation increased with increasing relative humidity because of greater frost accumulation of the outdoor heat exchanger. Experimental results revealed that both unnecessary and late defrosting operations occur when a time-and-temperature defrosting control is used. Concepts of advanced defrosting controls that could feasibly reduce both frosting and defrosting losses were developed from experimental data. Frosting caused greater degradation of heating capacity than defrosting did. Cumulative frosting loss coefficients were calculated as a function of time, temperature, and relative humidity and are applicable to modeling of frosting losses calculated in a seasonal performance program.