What is the purpose of HVAC compressor?

compressor is one of the essential component of an Air-Conditioning Loop, its basic functioning is to increase the pressure and temperature of the refrigerant which is then passed through the condenser where heat exchange takes place thus reducing the temperature, keeping the pressure intact.

then comes the expansion valve which reduces both the temperature and pressure, thus we achieve a refrigerant at lower temperature and pressure, which is used to cool down the room, the exit from the evaporator is then connected back to compressor inlet via accumulator