Performance investigation on a precision air conditioning system with a condensation heat recovery unit under varying operating conditions

•The performance of a constant temperature industrial air conditioner was experimented.•Cooling capacity rises by 33 % when compressor frequency double increases to 240 Hz.•COP is enlarged 2.2 times as the compressor frequency decreases from 240 to 120 Hz.•Cooling capacity and COP both show fluctuation with the increase in air volume.•Cooling capacity first rises to 1510 W and then falls to 1397 W with cooling water heated. The precision air conditioner is usually used in many occasions where the temperature and humidity are required to be constant. To guide the performance optimization of the precision air conditioners, the experimental investigation on the performance of a precision air conditioning system with condensation heat recovery was carried out. The influences of four vital parameters which are the compressor frequency, air volume and cooling water flow on the system performance were tested and analyzed respectively. It results that the cooling capacity is increased (approximately 33 %↑) while the coefficient of performance (COP) gradually decreases from 4.98 to 2.26, when the compressor frequency ranges from 120 Hz to 240 Hz. With the circulating air volume increases from 490 m3/s to 1141 m3/s, the cooling capacity and COP are both elevated, by 35.6 % and 42.6 %, respectively. Moreover, with the increase of cooling water temperature (Tw), the cooling capacity is increased at Tw ∈ [289 K, 295 K] but decreased at Tw ∈ [295 K, 301 K], gradually. It can be concluded that the phenomenon of performance variation in the precision air conditioner is relatively complex for the influence of the condensation heat recovery.