2. Working principle: Based on the principle of reverse Carnot cycle, using a small amount of electric energy, the compressor is used to evaporate ordinary substances into a gaseous state in the evaporator after passing through the expansion valve.
3. Heat transfer: Absorb a large amount of heat energy in the air, the gaseous working medium is compressed by the compressor into a high-temperature, high-pressure gas, and then enters the condenser to release heat to heat the drying medium.