The "new" comfort industry shifted course dramatically with the advent of the 1973 oil crisis. Suddenly, efficiency became the driving force behind both marketing and engineering efforts. DOE standards would indicate the HVACR industry's course for the next 20 years. Computer simulation techniques were a critical design tool for the 1970s and beyond.

The '70s began with an emphasis on comfort -- total comfort in fact. Electronic air cleaner ads promised to make people breathe easier, humidifier ads promised not only better health, but furniture wouldn't fall apart.

ASHRAE committees were busily analyzing the technical details of human comfort, and commercial HVAC systems were designed to offer pinpoint control of both temperature and humidity for busy, happy occupants. Energy was cheap and reheat systems seemed eminently practical.

The 1973 energy crisis ended the industry's primary goal of making people comfortable -- for nearly 20 years.

Long lines at gasoline stations, building energy wardens, the dictate to turn down, turn off, save energy, launched an industry-wide effort to re-design and invent, a mad scramble in search of energy-saving products.

The Federal Government got into the act, creating first an Energy Office, then a full fledged Department of Energy. Early officials threw money at every seemingly logical project to save energy -- they even tried to reinvent heat pumps (already viable and available). Meeting new energy standards sucked up years of manufacturers' engineering time, postponing indefinitely introduction of new products that provided comfort.

Building owners began to discover very often their buildings had 100% redundant heating/cooling capacity-victims of multiplying fudge factors and the old adage, "you're only in trouble when there's not enough cooling." This disillusionment laid the groundwork for the rise of Design/Build contractors and the end of a love affair with the plan and spec process and consulting engineers.

Slowly people discovered their hastily erected school buildings thrown up to house a booming school population were energy hogs. Life cycle costing studies and methods grew in popularity and energy opportunists and charlatans with mysterious fuel-efficient burning pyramids, cars that ran on water alone, and black boxes with strange powers were everywhere.

By 1974, programmable calculators were used for building simulations, and value engineering was the buzzword in the design community.

Building and industrial owners hired energy managers to analyze payback and feasibility of energy saving equip¬ment investments.

Forecasters said heat pumps would outsell air conditioners in less than five years, and one million heat pumps would be sold annually by 1980.

By the mid '70s, rooftop replacements really took off, accounting for 25 to 30% of rooftop equipment sold. There were even some fears that shortages might occur if the replacement market were to collide with an expected surge in new construction.

Fiberglass duct systems were developed and heavily promoted for their ability to save both energy and fabrication time, with little investment for a contractor to get into the business. Sheet metal contractors resisted, “too itchy,” they said. “Sheet metal is better,” they exclaimed. Fiberglass duct board captured 25% of the market by the end of the decade.

In the late '70s, two obscure scientists, Rowland and Molina, reported that the HVAC industry might have a problem with their "wonder" refrigerant.

The chlorofluorocarbon family of near-perfect, ultra-stable refrigerants appeared to be dangerous to the world's ozone layer precisely because of their stability -- one of the key properties that made CFCs such a desirable refrigerant. In 1978, Robinaire introduced their first prototype refrigerant recovery system.

During this intense period of experimentation with technology, ultrasonic combustion oil burners, promising efficiency increases of 20 to 30%, glass tube solar concentrators, and self powered natural gas furnaces boasting efficiencies of 85% plus, were just some of the products that never got off the ground.

The '70s ended on a note of uncertainty: another energy crunch ensued, the CFC problem, not yet a major force for change, hung ominously on the horizon and government seemed intent on dictating which HVAC equipment and products could be used to heat and cool U.S. commercial buildings.