In 1981 William Shurcliff published Air-to-Air Heat Exchangers for Houses. He was an extraordinary scientist. He received his BA, PhD in physics, and a degree in business administration all from Harvard. In May of 1942 he started working on the Manhattan Project developing the atom bomb. In the late 1940s he worked for Polaroid Corporation where he attained more than twenty patents. In 1962 he published a book on Polarized Light, and he went on to play an outspoken role in defeating plans for supersonic passenger planes in order to restrict the flight of supersonic transports over populated area where breaking the sounding barrier would have caused extraordinary damage.
Then in the 1970s and 1980s he became an ardent advocate for passive solar building design and super-insulation. It is extraordinary to think of what he would be working on now.
At the beginning of his book on air-to-air heat exchangers – written 40 years ago – he says, “Interest in air-to-air heat exchangers is increasing by leaps and bounds. As recently as 1979 many architects and builders had never heard of them. Yet today practically all architects and builders (and many home-owners also recognize the need for them in tightly built houses.”
He goes on to point out that the surge of interest may be explained by the fact that “our understanding of indoor pollutants and the health threats they pose has increased.” New kinds of pollutants have appeared on the scene like the formaldehyde compounds in particleboard. “Today’s new house are much tighter than house built decades ago. The threat of indoor pollution is being publicized in the popular press.”
The book includes details on the fundamentals of air, pollutants, radon, natural infiltration, water vapor, humidity condensation and water transfer, and describes different types of exchanger design.
The chapter on sensors, controls and fail-safe devices includes manual control, control by timer, control by temperature, control by humidity, control by concentration of pollutant, control by utility activation, and inverse-of-windspeed control which could solve one of the major problems with whole building ventilation: more ventilation is required in the shoulder seasons when the HVAC system isn’t running and the windows aren’t open. He suggests that “it would not be difficult to employ an above roof mounted hot-wire anemometer” to control the speed of the ventilation in harmony with the wind loads. More wind means more infiltration and a lower need for ventilation.
He includes the plans for the construction of a DIY HRV along with description of products that were commercially available in 1981.
There is a huge amount of worthwhile information embodied in books such as this, much of which has been lost, much forgotten, and much continuously being reinvented. We need to bring information like this back, to save time, and not repeat mistakes. With all of our technology, we should be able to at least accomplish that. It’s like resurrecting an old house. It sometimes seems quicker to just tear it down and start over, but a great deal can be lost in the process.