2. Objectives When you have completed this session, you should be able to: 1.Explain the basic principles of heating, ventilation, air conditioning and refrigeration. a.Explain the principles of heating. b.Explain the principles of ventilation. c.Explain the principles of air conditioning. d.Explain the principles of refrigeration. 2.Describe the principles that guide HVAC/R installation and service techniques. a.Identify common safety principles and organizations. b.Describe the importance of LEED construction and energy management.

3. 1.1.0 Forced-Air Heating Examples of forced-air heating, using the basement or attic to house the installation.

4. 1.1.0 Hydronic Heating Examples of hydronic heating, with the installation in a basement or on the 1 st floor of the living area

5. 1.2.0 Improved Air Quality

6. 1.3.0 Basic Refrigeration Cycle

7. 1.3.0 Heat Pumps

8. 1.4.0 Temperature Ranges 60°F is generally considered to be the dividing line between air conditioning and refrigeration.

9. 2.0.0 The successful technician… always follows good safety practices is conscious of the need to conserve energy and protect the environment follows applicable codes and standards

10. 2.1.0 Safety Tips: working at heights working with refrigerants and oils working around gas furnaces working around oil furnaces

11. 2.2.0 Energy Conservation Energy recovery ventilators provide fresh air, while also exchanging energy between the indoor and outdoor air. This reduces the heating or cooling load of the fresh air.

12. 2.2.1 LEED Rating System: Sustainable sites Water efficiency Energy and atmosphere Material and resources Indoor environmental quality Innovation and design

13. Wrap Up – Trade Terms: Compressor: Converts low-pressure, low-temperature refrigerant gas into high- temperature, high-pressure refrigerant gas. Condenser: A heat exchanger that transfers heat from the refrigerant flowing inside it to the air or water flowing over it. Evaporator: A heat exchanger that transfers heat from the air flowing over it to the cooler refrigerant flowing through it.

14. Wrap Up – Trade Terms (continued): Expansion device: Also known as the metering device. Provides a pressure drop that converts the high-temperature, high-pressure liquid refrigerant from the condenser into the low-temperature, low-pressure liquid refrigerant entering the evaporator. Heat pump: An air conditioner that produces heat by reversing the refrigeration cycle.

15. Wrap Up – Trade Terms (continued): Heat transfer: The transfer of heat from a warmer substance to a cooler substance. Hydronic: A heating or air conditioning system that uses water as a heat transfer medium. International Building Code: A series of model construction codes. These codes set standards that apply across the country.

16. Wrap Up – Trade Terms (continued): Mechanical refrigeration: The use of machinery to provide cooling. Mechanical refrigeration cycle: The process by which a circulating refrigerant absorbs heat from one location and transfers it to another location. Noxious: Harmful to health. Toxic: Poisonous.

17. Wrap Up NEXT SESSION… TECHNICIAN LICENSING AND CERTIFICATION; CAREERS IN THE HVAC TRADE Read Sections 2.3.0 through 3.3.0; complete the 1.0.0 and 2.0.0 Section Review