One of the longest running “reality” shows is “This Old House” on public television. Truth be told, many viewers tune in to see a wall come (intentionally) crashing down as part of the renovation or an especially tricky installation successfully completed. But it is also a show to take note of some interesting and unique technologies.

Consider, for example, a program a while ago that showed a residential chiller. And not just a basic chiller, but one that is a reverse-cycle liquid chiller.

That technology shown came from Unico Systems, whose officials called it “the latest innovation in home comfort - an outdoor unit for residential and light commercial applications which provides both hot and cold water for central heating and/or cooling.”

According to Shawn Intagliata, director of business development, the unit “can provide zoned cooling or heating with just a single unit, so you can use multiple air handlers to provide cooling or heating only to those areas in need of it at any given time.”

Refrigerant in the unit chills water that goes through insulated piping into the house and is pumped into a number of air handlers. The liquid then comes back to the outside unit to be rechilled.

Intagliata noted the product, called the Unichiller, could be undersized up to 20 percent if there is more than one zone and if not all the zones are operating at the same time. An ASHRAE Manual N load diversification calculation can also be done to see if the chillers can be undersized further.

The chillers are designed for partial load allowing for the zoning. They come pre-charged and self-contained. A contractor connects the water piping and electrical power. Remote locations can be up to 300 feet away as long as the water lines are sized according to Manual N. There are two fans on each unit.

The chiller operates based on the water temperature sensed by the temperature controller inside the unit. Proponents of the technology said the chiller is quieter than a typical outdoor condensing unit. It is possible to bank multiple units for larger loads, according to Intagliata.

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Publication date:05/07/2007