A plate heat exchanger is a type of heat exchanger, also known as a heat transfer medium. During the process, heat is transferred from one medium to another, without mixing the two media.

The plate heat exchanger consists of corrugated plates that are assembled in a unique way, and there are gaps between the plates. In these intermediate spaces, two media circulate alternately: the heat absorption medium and the heat dissipation medium.

The device is sealed both outside and beneath the media in various ways. There are heat exchangers with bolted plates, which are expandable and transfer the flow differently.

Various types of plate heat exchangers are available, with a preference for plate heat exchangers where the plates are welded together.