本研究目的是採用家用除濕機為試驗樣機,研究以R-600a / R-290混合比例各為50 %之碳氫冷媒(HR-12)置換取代原試驗樣機所使用之R-134a冷媒,藉以瞭解並分析換裝碳氫冷媒後的家用除濕機實際運轉情形與系統性能各方面之表現,並從所得之相關數據來探討冷媒置換之可行性。 實驗結果顯示:對於原設計即有之家用除濕機系統而言,不變更其原有的設計而只將其所使用之R-134a環保冷媒置換成為HR-12碳氫冷媒時,冷媒之充填量約在45 %(60.8g)∼47 %(63.5g)時,其整體系統相關性能參數之表現為最佳情況。其中冷媒充填量減少了約55 %左右,除濕能力增加約8%∼14%,平均消耗電功率亦降低了約3 %,整體除濕效率比提升約12 %左右。若進ㄧ步將毛細管長度作適當縮短,其碳氫冷媒HR-12之充填量會更少而且充填量之有效範圍更廣,在除濕能力表現上亦有大幅度的增加,整體平均消耗電功率亦有相當可觀的節能呈現。此外,壓縮機的高壓排氣出口、低壓吸氣口以及壓縮機外殼的溫度均有下降的趨勢,此優異的表現可提高壓縮機之運轉壽命及其效率。 整體而言,不論是目前即有之家用除濕機或者各元件經過變更設計後之除濕機,在安全規範使用的範圍內(冷媒充填量小於150g),碳氫冷媒HR-12的確有足夠的能力來取代目前家用除濕機所使用的R-134a冷媒。
The objective of this study is to evaluate the feasibility and operation performance characteristics of a residential dehumidifier when it is converted into HR-12 from R-134a refrigerant. HR-12 is a mixture of R-600a and R-290 refrigerants blended in a 50-50 ratio (measured by mass). Without change of any components of the dehumidifier, experimental results show that better performance characteristics could be achieved if 60.8 g to 63.5 g of HR-12 refrigerant, which is only 45% to 47% amount of original R-134a refrigerant, is charged in the system. In other words, 55% reduction in refrigerant charge but water removal capacity of the humidifier is improved 8%∼14%, average power consumption saving is 3% and overall dehumidification efficiency improves by around 12%. It is found that the performance characteristics of water removal capacity and power consumption saving could be improved further if the original capillary tube is cut to an appropriate shorter length plus less HR-12 refrigerant charged. Amount of HR-12 refrigerant charge is insensitive in a wider range to performance characteristics of the dehumidifier. Compressor discharge temperature, suction temperature and compressor casing temperatures are all found lower than original design. It is expected that longer life cycle and higher efficiency of compressor will be resulted. Generally speaking, conversion of residential dehumidifier from R-134a into HR-12 refrigerant (charged amount less than 150 g) is feasible either with or without change of components of the original unit design.