Record Details
An analysis of the control and economics of a three-pipe heat pump system
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | An analysis of the control and economics of a three-pipe heat pump system |
| Names |
Waymire, James Lee
(creator) Thornburgh, George E. (advisor) |
| Date Issued | 1967-05-12 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | The use of a three-pipe distribution system is known to impair the operating costs of an air conditioning system. Additional costs are encountered because heating water and cooling water are mixed in a common return pipe after use by the various air conditioning units. This investigation covers the design and installation of an automatic temperature control system to operate a heat pump air conditioning system utilizing a three-pipe distribution system. The investigation also was directed toward the study of the economics of the three-pipe system while in use providing heating and cooling to an industrial plant. The experiment was performed with a centrifugal refrigeration compressor heat pump of 497 tons of refrigeration capacity. Tests were conducted at outside air temperatures of 42, 51.5, and 53°F. During each test, heating water flow, cooling water flow, heating supply water temperature, cooling supply water temperature, common return water temperature, and cooling return water temperature were measured. Sufficient data were recorded, during each test, to determine the heating load, cooling load, and operating penalty due to the mixed flow condition in the common return. These results were correlated with outside temperature occurrence data to determine the additional annual operating cost encountered because of the use of a three-pipe system. The additional annual owning cost of a conventional four-pipe system above that of the three-pipe system was determined. This cost included items for depreciation, interest, and taxes. A comparison between the annual owning and operating costs of the three-pipe system and the four-pipe system was made. It was determined that the three-pipe system installed in the particular industrial plant investigated exhibits a cost approximately one-third of that of the conventional system used for comparison. It was determined that the three-pipe system would become relatively less costly to own and operate if applied to a system with similar loads in all areas, if used with a heat pump system, and if used with a system employing final heat transfer elements selected for as high a water temperature drop or rise as possible. The three-pipe system would become relatively more costly to own and operate if the system piping runs were short, if the individual air conditioning units were larger, and if a system employing separate heating and cooling sources was used. |
| Genre | Thesis/Dissertation |
| Topic | Air conditioning |
| Identifier | http://hdl.handle.net/1957/47044 |
