Heating and Air Conditioning

Residential heating and Air

DEVELOPMENT OF REFRIGERATION SYSTEMS

• Since the first vapor-compression refrigeration system was invented by Jacob Perkins in 1834, more than 50 chemical substances have been used as refrigerants in refrigeration and air-conditioning systems. The development of refrigeration systems using CO2 as the refrigerant started in 1866, when an ice production machine that used CO2 was invented by Thaddeus S.C. Lowe.

REFRIGERANTS AND THE ENVIRONMENT

• Along with the worldwide effort to protect the ozone layer, global warming--the second environmental effect of refrigerants--has garnered a great deal of public attention, as it threatens to become the dominant environmental issue for decades to come. In 1985, the World Meteorological Organization's international conference concluded that in the first half of the next century a rise of global mean temperature could occur that would be greater than any in human history, caused by increasing concentrations of greenhouse gases. As shown in the table on this page, greenhouse warming occurs when carbon dioxide (CO2), released mostly from the burning of fossil fuels (oil, natural gas, and coal), and gases such as methane (CH4), nitrous oxide (N2O), ozone (O3), CFCs, HCFCs, and water vapor build up in the atmosphere.

Career directions

• In the winter, we depend on heaters to keep our homes, schools and offices warm. In the dog days of summer, we depend on air-conditioners to keep homes and workplaces cool and comfortable. And year round, we depend on refrigeration systems to store and transport food, medicine and other perishable items. Our daily comfort and the economic health of many of our businesses depend on heating and air-conditioning systems.

Job Opportunities

• Jobs in the industry are predicted to increase by 24 percent through 2010. Prospects are expected to be very good for skilled technicians, particularly for those with technical school or formal apprenticeship training to install, remodel and service new and existing systems. In addition to job openings created by employment growth, thousands of openings will result from the need to replace workers leaving the field.

Certification

• Similar to ASE certification practice in the automotive industry, the heating and cooling industry recently adopted a standard certification program for experienced technicians. The Air Conditioning Excellence program is available to both installation and service technicians through an association called North American Technician Excellence, Inc. Technicians must pass a core exam that covers safety, tools, soft skills, principles of heat transfer and electrical questions. They must also pass one of five specialty exams. Specialties include air conditioning, air distribution, gas heating, heat pumps and oil heating.

Job Opportunities

• Most HVACR and plumbing contractors report that their number-one business problem is finding a sufficient number of competent trained employees. So get some formal training and you will have no problem finding employment almost anywhere in the U.S.