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Theory of Heat And Refrigeration
When the nice days of Spring time comes, ones thoughts turns to love. But when the hot days of Summer comes, ones thoughts turn to the Air Conditioner.
 More of this Feature
Part 1: Basic Principle Of Air Conditioning
Part 2: Temperature
Part 3: BTU's and Calories
Part 4: Heat Transfer
Part 5: Temperature and State Changes
Part 6: The Effects of Pressure on Boiling Points
• Part 7: Pressure/Temperature Relationship
Part 8: The "Comfort Zone"
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Pressure/Temperature Relationship

Raising the pressure of a vapor raises its temperature; lowering the pressure decreases its temperature.


In an air conditioning system, a compressor is used to increase the pressure of the refrigerant; this raises its temperature. The refrigerant vapor entering the condenser is hot.


In all air conditioning systems, an expansion valve is used to lower the pressure of the refrigerant; the refrigerant in the evaporator is cold.

Automotive A/C Systems are designed to operate at pressures that keep the refrigerant at the optimum temperature for taking heat out of the passenger compartment.

Next page> The "Comfort Zone" > Page 1, 2, 3, 4, 5, 6, 7, 8

Additional information provided courtesy of ALLDATA

© 2003 - 2004 Vincent T. Ciulla

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