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Physical Principles

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The four known states of water also apply to air conditioning system refrigerants.

GWWN87-0531Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.
  1. Gaseous (invisible)
  2. Vapor
  3. Fluid
  4. Solid

When water is heated in a vessel (heat absorption), water vapor can be seen to rise. If the vapor is further heated through heat absorption, the visible vapor turns into invisible gas. The process is reversible. The warmth is extracted from gaseous water, vapor forms first, then water and then ice.

GWWN87-0529Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

A - Heat absorption

B - Heat emission