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A programmable zone-control thermostat with a large digital readout shows information about the temperature and comfort conditions in the zone.
Photo by Zonex
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This zone-control thermostat is programmable and controls the temperature in one room or in a group of rooms in one zone.
Photo by Durodyne
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The master zoning control receives signals from the zone thermostats and controls each damper, as well as the furnace and the central air conditioner.
Photo by Zonex
Question: Some rooms in our house are too hot or too cold, so someone is always complaining about the temperature. What can we do to even out room temperatures? Will doing this lower our utility bills?
Answer: It’s likely there’s not a single home in the country that has even temperatures throughout all its rooms. Zone-control systems offer an energy-efficient alternative to trying to control individual room temperatures.
Many factors, such as the length of ductwork, duct bends, orientation to the sun, and the number of windows and exterior walls can impact a room’s air temperature. The items in a room—such as a large TV in a small room—can also affect the air temperature.
Usually, it is not desirable to have all the rooms at the same temperature. Depending on the activity level in various rooms, different temperatures may be more comfortable for you and your family. Some people simply prefer a warmer or cooler room.
It’s hard to achieve even room temperatures in homes with a single furnace or heat pump. If you set the thermostat to keep the chilliest room warm, this results in other rooms becoming too warm. According to the Department of Energy, for each degree you can set the thermostat lower for an eight-hour period, heating bills can be reduced by up to 1 percent.
Installing an automatic zone-control system is the best and most energy-efficient method to control individual room temperatures. A zone-control system adjusts special duct dampers, based on the actual and desired room temperatures.
Many homes have access to only main ducts, which later branch out to the individual rooms. In this case, a zone-control system will control the temperatures in each grouping of rooms, such as all the bedrooms in one zone, the kitchen/dining areas in another, and the living room in a third. Although it is optimal to control each room independently, having just three or four zones is adequate for comfort and energy savings.
A programmable thermostat is mounted in each room or zone grouping to control the motorized duct damper leading to it. If the room is too warm during winter, the damper in the duct leading to that room partially closes. For example, a zone thermostat may continuously readjust the damper position throughout the day as the intensity of the sun shining through a window changes.
The majority of the energy savings with an automatic zoning system is realized because each room temperature can be varied throughout the day. There is no need to keep the bedrooms toasty warm during the daytime or the living room warm overnight. The programmable thermostats are designed to bring room temperatures back up without having the backup resistance elements come on.
The various designs of zoning dampers range from just a simple flat damper to bladders, which inflate with air to close off the ducts. They all function equally well.
With the many new thermostats and use-control electronics on the market, adding a zoning system requires professional installation. Talk to a qualified technician to design a system that works best for your home.
The following companies offer zoning systems: Aprilaire, (800) 334-6011; Arzel Zoning Technology, (800) 611-8312; Duro Dyne, (800) 899-3876; EWC Controls, (800) 446-3110; and Zonex Systems, (800) 228-2966.
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