Investigation of load variations with seasonal conditions affected to coefficient of performance of air to water heat pump
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Abstract
Following EN255-3 standard, coefficient of performance for tapping process (COPt) was defined. As the variation of temperature among different seasons, the load variations as outlet hot water temperature (Two) and the variation of temperature as ambient temperature (Ta) and air humidity from air to water heat pump (11 kW) were studied to obtain COPt. The results showed increase of ambient temperature enhanced COPt because lower electrical energy input (Wet) was induced by higher ambient temperature. Moreover, higher COPt was affected by higher air humidity. The results were shown that decrease of outlet water temperature affected to higher electrical energy input and enhanced higher COPt. This study could be concluded that ambient temperature was higher with lower outlet water temperature affected to lower electrical energy input for tapping process due to lower load of compressor. The overshot electrical energy input for tapping process was observed at specified ambient temperature for each outlet water temperature and it was resulted to diminish COPt significantly.
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References
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