During the mid-1930s, I began a job with a small company to learn about a new forced-warm-air heating business. Shortly thereafter, the company built a new office building designed by its chief engineer. Although this was long before energy conservation became a popular topic, the costs of installation and operation were important because the Great Depression was in full swing.
As office buildings go, the new building was not very large. It was two stories and had a flat roof that sloped from the front to the rear of the building. It was heated with a gas-fired, forced-warm-air furnace located at the rear of the showroom floor. The ducts were exposed so potential customers could see how the new square ducts could be located at a basement's ceiling and, therefore, not take up usable room space.
All of the city water came from deep wells, so it was cool enough to be used to provide air conditioning in the building. The water first was circulated through eight-row coils located in the furnace casing. After leaving the coils, water was piped to the high part of the building, where it was sprayed onto the roof. After flowing over the roof and, therefore, cooling it, water collected in the eaves trough and flowed through the downspout. The discharge end of the downspout was altered to allow sprinkler hoses to be attached, which provided water for the lawn surrounding the building.
This method allowed the same water to be used to cool and dehumidify the air within the building, remove solar heat load from the roof, and irrigate the lawn. It shows what can be done if one has an active imagination.
Kenneth E. Robinson, CIH