1 Welcome to HVAC Fundamentals of HVAC PPT

1 Welcome to HVAC Fundamentals of HVAC PPT a 7 m 01 Final Copyright 2002 General Motors Corporation

2 The material contained in this course component was accurate and current at the time of course development.

3 Objective Describe theory and operation of: t HVAC Systems t Cooling Systems t Air Distribution Systems t Principles of Refrigeration t Air Conditioning and Comfort t Properties of Heat and Temperature

4 Objectives Describe theory and operation of: t Vaporization and Condensation t Basic Refrigeration cycle t Factor Affecting Heat Transfer

HVAC Heating Ventilation Air Conditioning 5

6 HVAC Sub Systems • Cooling • Refrigeration • Air Distribution

7 Refrigeration System t CCOT t VDOT t CCTXV t VDTXV t Types of Refrigerant l l R-12 R-134 A

8 CCOT t Condenser t Accumulator-Dryer t Evaporator t Muffler t Pressure Cycling Switch t Thermostatic Switch t Pressure Cut-off Switch t Pressure Sensor

9 VDOT t Condenser t Accumulator-Dryer t Evaporator t Muffler t Pressure Cut-Off Switch t Pressure Sensor

10 CCTXV t Condenser t Receiver-Dryer t Evaporator t Muffler t Thermostatic Switch t Pressure Cut. Off Switch t Pressure Sensor

11 VDTXV • Condenser • Receiver-Dryer • Evaporator • Muffler • Pressure Cut-Off Switch • Pressure Sensor

12 Rear Units t Thermostatic Expansion Valve t Evaporator t Refrigerant Lines

13 Cooling Systems Air Intake Condenser Radiator Fans Seals and Shroud

14 Air Distribution System t Blower t Evaporator t Heater t Air Doors t Air Ducts t Control System

15 Principles of Refrigeration t Behaviors of Heat t Properties of Heat t Behavior of Refrigerants t Effects of heat and pressure on liquids and gases

Air Conditioning and Comfort t Moisture t Heat t Pollen t Dust 16

17 Heat versus Temperature t Heat is measured in BTUs t Heat is the energy in a substance t Temperature is measured in degrees t Temperature is the intensity level

18 Heat Transfer

19 Changes in state of matter

20 Heat of Vaporization t A specific amount of heat is needed to change a liquid to a vapor t Known as latent heat t Latent heat of water 970 BTU/lb t Latent of 134 A 93 BTU/lb

Vaporization and Condensation t Vaporization is is the addition of latent heat to a liquid t Condensation is the removal of latent heat from a liquid. 21

22 Pressure Temperature t The pressure acting on a liquid is increased, the boiling point of the liquid increases t Lowering the pressure acting on a liquid lowers its boiling point

Effects of pressure on gases and vapors Low pressure low temperature High pressure high temperature 23

24 Basic Refrigeration cycle

25 Controlling refrigerant flow

Factor Affecting Heat Transfer t Coolant Fan t Condenser t Blower Motor t Humidity t Sun Load 26

27 Summary

28 Thank you for attending Fundamentals of HVAC Copyright 2002 General Motors Corporation