You hear a lot these days about variable-speed heating and air conditioning and how that technology has improved HVAC systems in recent years. But what is all the excitement about? Here’s your crash course in variable-speed HVAC systems and what they can mean for your home heating and cooling needs.
What is a Variable-Speed System?
Traditional HVAC systems—heating and cooling—operate as single speed: on or off. You’ll also hear about two-stage systems, which operate in two speeds: high and low. By contrast, a variable-speed system operates at multiple different speeds, depending on the heating or cooling needs of your home. A variable-speed furnace and air conditioner will be equipped with a variable-speed fan motor, which regulates the airflow in conjunction with the heating or cooling output.
You’ll also hear the term modulating heating or air conditioning. Essentially, this means that the heating or cooling effect automatically raises or lowers, depending on fluctuations in outside temperatures.
For example, if the outside temperature is 80° F and your thermostat is set at 74°, your AC would only need to compensate for the 6° difference. So it doesn’t need to operate at full capacity, which is what a traditional system would call for. It can handle that 6° difference at, say, 30% capacity. Because of their greater range of output options, variable-speed systems provide the most effective modulating ability.
What are the Advantages of a Variable-Speed System?
Variable-speed systems have a number of advantages over single- or two-speed systems including:
- Increased Comfort. Because of the range of heating and cooling output and airflow, variable-speed systems provide the ultimate in home comfort. You will always have precise temperature control that adjusts automatically to changing weather conditions. In winter that means a steady, cozy temperature. In summer, it not only means a steady cooling temperature, but precise humidity control, as well. Not only does lowered humidity increase your home’s comfort, it also protects it from mold. And for those who live in areas with extreme temperature fluctuations—like the upper Midwest—these systems typically provide extra capacity to handle those extremes.
- Energy Efficiency. A variable-speed system isn’t always at capacity when in operation and it also has shorter operating cycles. Because of those two features, it provides the best in overall energy efficiency, which translates to lowered utility bills for you.
- Improved Reliability. Many of the newest systems have improved electronic controls that allow the system to protect itself from operational failures in ways that traditional systems can’t.
What Does a Variable-Speed System Cost?
The cost of a variable-speed furnace compared to a standard unit will depend on other features and which specific units you’re comparing but in general, you can expect between $600 and $1,200. The air conditioning unit would add in approximately $1,500 to $2,000, again depending on other features you may be comparing.
At Stay Comfy, we recommend the Carrier line of furnaces and air conditioners for their excellence in quality, reliability, and service.