Can air conditioners provide cooling in winter?

In winter, the air conditioner can still operate for cooling under certain circumstances.

Generally, air conditioners can still perform cooling operation when the outdoor temperature is about 10 degrees Celsius and the indoor temperature is about 20 degrees Celsius.

In some special places such as computer exchange centers, libraries, etc., refrigeration is also required in extremely low-temperature environments in winter, so it is necessary to specially develop refrigeration air conditioners for subzero temperatures.

Extended information

Principles of air conditioning and refrigeration

Liquid vaporization refrigeration uses the heat absorption when the liquid vaporizes and the heat release effect when it condenses to achieve refrigeration. The liquid vaporizes to form steam. When the liquid (refrigerant) is in a closed container, there is no other gas in the container except the liquid and the steam generated by the liquid itself. The liquid and steam will reach equilibrium under a certain pressure. At this time, The gas is called saturated steam, the pressure is called saturation pressure, and the temperature is called saturation temperature.

At equilibrium, the liquid no longer vaporizes. At this time, if part of the vapor is removed from the container, the liquid must continue to vaporize and generate part of the vapor to maintain this balance. When a liquid vaporizes, it absorbs heat, which is called latent heat of vaporization.

The latent heat of vaporization comes from the object being cooled, causing the object to be cooled to become colder. In order for this process to continue, the steam must be continuously removed from the container and condensed into a liquid before returning to the container.

If the steam extracted from the container is directly condensed into a liquid, the temperature of the cooling medium required is lower than the evaporation temperature of the liquid. We hope that the condensation of the steam is carried out at normal temperature, so the steam needs to be The pressure is increased to the saturation pressure at room temperature.

The refrigerant will evaporate at low temperature and low pressure, producing a cold effect; and condense at normal temperature and high pressure, releasing heat to the surrounding environment or cooling medium. Steam condenses at normal temperature and high pressure and becomes a high-pressure liquid. Its pressure also needs to be reduced to the evaporation pressure before it can enter the container.

The liquid vaporization refrigeration cycle is composed of four processes: vaporization of the working medium, steam pressure increase, high-pressure steam condensation, and high-pressure liquid depressurization.

Reference: Baidu Encyclopedia: Air Conditioning