When Air Conditioners first came out, they were a commercial-only piece of equipment. They were almost always custom designed and installed equipment. The first major system was built by Willis Carrier to regulate humidity for a printing company. There was no going out to the store or your contractor to buy this technology. It was made from scratch.
The first air conditioners were installed in factories. These started out with textile mills and pharmaceutical companies in the 1910s. In the 1920s, department stores and movie theaters would start investing in air conditioners. In these days, a large department store could get hot enough for customers and workers alike to faint. Cool stores attracted customers looking to escape the heat.
The Milam Building, in San Antonio, Texas would later be built specifically to be air conditioned from top to bottom. The entire building had special accommodations built-in to ensure consistent airflow to every floor, room, and store. This custom system was first put to use in 1928 and would not be retired until 1989 after a full 60 years of service.
These innovations all lead to better technology, but it still was not accessible. These 1920s systems were hand-designed, in many cases by Willis Carrier himself. His sales team could pitch an air conditioner to any client for any purpose and he would design whatever it took to make it work. This isn’t entirely unique today, but at the time, few people had the knowledge and skill to design such systems and even fewer stock parts existed to build from.
The first viable means of air conditioning a home came about in the 1930s. HH Schultz and JQ Sherman patented the first window air conditioner. It was a viable, mass produceable way to cool a room. The problem of cost however, still remained. The US was just beginning to crawl through the great depression. Few people could afford the luxury of an air conditioner, but at least it was possible to install one without an entire construction crew.
Issues with cost would be resolved by a roaring post-war economy. Unemployment was near non-existent in the US. Between decades of improved design and plentiful cash, sales were booming. In 1947, the window air conditioner would be made more compact and see 43,000 sales. For a country with 144 million people, this is nothing to sneeze at. It’s the beginning of a cooling revolution. By the 1950s, the post-war economy would push sales past 1 million units in 1953 alone. Air conditioning was becoming common in the states.
By the 1960s, 80% of US homes would have some form of air conditioning. Window units were cheaper than ever. New homes were built with central air conditioning as the technology boomed. Unbearably hot places like Arizona and Florida saw their populations explode as it become possible to live in comfort year-round.
Revolutionary New Approaches
The 1970s saw some of the biggest innovations in air conditioning history: the split system and efficiency standards. Central air systems up to this point were essentially packaged systems. Cool air was forced through ducts from the air conditioner into the home or office. It was horribly inefficient.
New, split-systems separated the condenser and evaporator into two separate modules. The very first mini-split systems began to hit the market. Air conditioners began to crawl towards improved comfort and cutting back on waste. These new systems could eventually be configured into multi-zone systems. With looming requirements on improved efficiency, it became essential to save energy everywhere.
The ripples of the energy crisis and our push for low-power AC can still be felt today. Air Conditioners now use about half the power they did in the 1990s. The figure is even greater compared to those old systems of the 70s.
Multiple Threads Coming Together
The basics of refrigeration were experimented on in the 1700s. Products were devised and marketed in the 1800s. Electricity and engineering would create the first large scale air conditioners in the opening years of the 1900s. Sales of refrigerators and accidental deaths from them would fuel refrigerant research. A massive demand for comfort and a booming economy aligned just-right to make our modern, air conditioned world feasible.