How to Use a P-T Chart

Manufacturers of refrigerants, controls, and other suppliers distribute hundreds of thousands of pressure-temperature charts to the trade every year. It would be rare indeed to find a service technician who could not put their hands on a pressure-temperature card at a minute's notice.

In spite of the widespread availability and apparent reference to the pressure-temperature relationship, very few service technicians use the P-T chart properly in diagnosing service problems.

The purpose of this video is to not only demonstrate the proper use of the pressure-temperature relationship, but to also illustrate how it can be used to thoroughly analyze a refrigeration or air conditioning system.