A dedicated fan coil unit designed to condition up to 100 percent outside air is called a unit ventilator. They’re common in classrooms and other heavy-use areas that require a large volume of fresh air, at the rate of 15 to 20 ft3/min per person. Most units can be automated by a factory-installed control system designed to minimize energy use while maintaining a comfortable zone temperature. Some typical features are random start-stop (to minimize demand peaks on startup), relays to integrate all the systems on a central time clock circuit, and a warmup cycle.
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Excerpt from Energy Conservation Projects.