506 CURRENT TOPICS. [J. F. 1.

Heating by Reversed Refrigeration.--A. J. LAWLESS. (Heating, Piping and Air Conditioning, Vol. I2, No. 8.) In order that the all- electric heating and air conditioning installation in the new building of the United Illuminating Co. serving New Haven, Conn., Bridge- port and surrounding communities might be comparable in operating cost with either coal or oil for fuel, the reversed refrigeration cycle for extracting heat from 55 ° F. well water is employed. In the reversed cycle, the cooled medium is discarded from the system and the heat removed from the medium becomes the useful work of the system. In the simple air conditioning refrigeration cycle, for every 2oo B.t.u. removed from the cooled medium, approximately 47 B.t.u. of equivalent electrical energy is consumed; allowing for out- side losses, approximately 24o B.t.u. must be removed from the condensers. This indicated that for every B.t.u. of electrical energy used, 5.I B.t.u. is given up by the condensers. In reversed cycle heating systems this ratio of performance is decreased somewhat because of the increase in compression ratio in order to obtain con- densing temperatures sufficiently high for heating purposes. The overall ratio of the system is also further decreased slightly, depend- ing upon the additional electrical energy for the pumps and other equipment performing at a I to I ratio. Factors influencing the practicality of the reversed refrigeration cycle for building heating include the availability of a source of outside heat, cost of electrical energy, and whether or not summer air conditioning is desired. In some industries where refrigeration is required for processing in winter, it would be possible to use the heat given up by the con- densers for heating purposes. There are two natural sources from which heat may be extracted in winter: outside air and water. In cold climates, water becomes the only practical source and in the case under consideration private wells are used. In the winter the well water is cooled by the refrigeration evaporators and discarded; the heat removed is given up by the condensers to a closed system of hot water heating. In summer the well water is pumped through the evaporators, delivered to the various cooling units in the build- ing, and then returned to the condensers and discarded.

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