Evaporator is the machine inside the air conditioner. Heat exchanger is the machine outside the air conditioner. If heating, exchange the internal and external machines.
Difference of evaporator and heat exchanger:
1. In principle, there is no difference between the them. They all aim to achieve heat exchange between hot and cold fluids.
2. But neither should be confused.
(1) The concept of "heat exchanger" is more extensive and includes all "heat equipments". For example, radiation heat exchanger, convection heat exchanger, plate heat exchanger, needle heat exchanger, heat pipe heat exchanger, spoiler heat exchanger, regenerative heat exchanger, gas heat exchanger, gas and liquid Heat exchanger, etc. These are all called "heat exchanger".
(2) Of course, the evaporator, condenser also belong to heat exchanger. But this type of "heat exchanger" has a phase change, so they're a little special. Therefore, its name is usually in accordance with the working fluid phase , in order to show the difference with the ordinary heat exchanger. For example, the condensation of gas, called "condenser". Of course, the liquid evaporates, called the evaporator. However, they still belong to the category of heat exchangers.
(3) Other areas of special application include convection (shielding, high temperature, low temperature) superheaters for boilers, high temperature (low temperature) reheaters, economizers, etc. This type of "heat exchanger" is named for its purpose of use. In fact, these are also a class of heat exchangers for special or special applications.
Finally, the different methods or different types of heat exchangers will lead to different design and different different of the heat exchanger.