現今各國環保意識提升，而中央空調使用之冷媒容易跟大氣臭氧結合，使臭氧層漸薄，且利用冷媒吸收水之熱量，形成冰水提供，冷媒吸收之熱量再藉由冷卻水傳至冷卻水塔排放至大氣，加劇全球暖化，且壓縮機之高消耗功率也與現今能源議題相違背。
本研究利用水在負壓下沸點會降低之原理，使水在常溫下進行蒸發吸熱達到致冷之效果，而帶有熱量之蒸發水氣將其用水冷凝，形成熱水使用端。
研究目的為建立一真空致冷系統，利用水當冷媒，包含之閃蒸槽與冷凝槽、油式真空泵及真空助力泵，經過變頻器調整輸出功率，並記錄閃蒸槽及冷凝槽之溫度，計算致冷能力與製熱能力，找到此系統最佳操作點。
此系統經實驗得知，可將水由26℃降至18℃，也可將水由25℃升至35℃，而系統性能係數落在2.0~2.3左右，且此系統也有包含熱損失及其他外在因素計算，使研究成果更完整。
Nowadays, environmental protection awareness of various countries is increasing, and the refrigerant used in the central air conditioner is easy to combine with atmospheric ozone, making the ozone layer thinner, and using the refrigerant to absorb the heat of water to form ice water. The heat absorbed by the refrigerant is then transferred to the cooling tower through the cooling water for discharge to the atmosphere, global warming is exacerbated, and the high power consumption of compressors is also contrary to current energy issues.
This study uses the principle that the boiling point of water will decrease under negative pressure, so that water evaporates and absorbs heat at room temperature to achieve the effect of cooling, and the evaporated water vapor with heat condenses the water to form the hot water use end.
The purpose of the research is to establish a vacuum refrigeration system, using water as the refrigerant, the included flash tank and condensation tank, oil vacuum pump and vacuum booster pump, adjust the output power through the frequency converter, and record the temperature of the flash tank and condensation tank, Calculate the cooling capacity and heating capacity to find the best operating point of this system.
This system has been experimentally known to reduce water from 26°C to 18°C, or to increase water from 25°C to 35°C, and the system performance coefficient falls around 2.0 to 2.3, and this system also includes heat loss and other The calculation of external factors makes the research results more complete.
