Compression of the gas (increase in pressure) generates heat and the temperature increases; the expansion of the gas (reducing pressure) absorbs heat and the temperature decreases. The inlet tube of the vacuum pump collects water droplets and the outlet tube generates heat. This should be a physical phenomenon.
If the degree of water droplets and heat generation is abnormal compared to the past, please check whether the inlet and outlet pipes are too long and thin, whether they are smooth and unlocked, and if they have caused the input and output to malfunction. Is the pressure too low or too high?
If there are other unexplained phenomena, you can contact online at 1532 or 6166