As Congress continues to stay indoors trying to work out the country’s debt limit, trying to stay cool while tempers heat up, it’s time to look at how they’ve managed to keep the temperature in the Capitol at a reasonable level over the last 80 years.
Until Willis Carrier invented the first viable air-conditioning machine in 1902, the only way to keep cool was to either flee DC for the season, or to live in a building that was built to take advantage of any change in temperature or breeze that did happen. In this way, the Capitol was built to allow for air to flow beneath the House and Senate chambers, in order to keep the Congresspeople from boiling.
In 1928, the architect of the Capitol finally decided that this would no longer do, and he posted a request for proposals to air condition the House chambers. The proposal submitted by Carrier was accepted, and five years later, Willis Carrier himself was in DC, describing to the Washington Society of Engineers how they had done so.
It had not been an easy task. Where most places that had AC installed until then were either factories or theaters, the Capitol had many windows that had to be dealt with — and particularly, skylights, which made it much more complicated. Furthermore, the installers could not simply add ducts willy-nilly, but instead had to be installed without changing the fabric of the Capitol building.
Fortunately, the walls of the Capitol were so thick that it was possible to route the air ducts through them.
A 1935 article explains how the system works: Air is pulled in from outside and brought into a chamber in which cooled air is being continuously sprayed. This cools down the air, as well as removing the humidity. The cooled air is then brought through a filter which removes any dust particles and is then circulated throughout the Capitol.
One thing that the article does not mention at all is how the water is cooled in the first place — the idea of refrigeration was, by then, an old one. In fact, it had been John Gorrie, a Florida physician, who had built the first refrigeration system — in 1842. Unfortunately, although his prototype worked, it was never put into production and Gorrie died a few years later, a pauper.
Over the next 60 years, refrigeration became a fact of life, and home fridges were sold as early as 1911. However, it was not until 1902 that Carrier’s method for cooling large spaces paved the way to making DC an acceptable place to spend the summer.
Gorrie, for his part, remains in the Capitol as well: His statue can be seen in the old House chamber, as part of the National Statuary collection.