If you’re in the market for a new air conditioner, you have probably encountered the terms “single-stage”, “two-stage” and “variable speed”. Unless you’re in the HVAC business like we are, you probably aren’t sure what exactly these phrases mean and how they should affect your decision – or why you should even care to know the difference. Well, we’re here to shed some light on these terms and their significance to you. In fact, the type of motor with which your new AC is equipped will have an impact on both your electric bill and your comfort.
One Trick Pony – Single-Stage Motor
Every air conditioner has a blower (a.k.a. fan) motor, located inside the air handler. The main function of the motor is to circulate conditioned (heated or cooled) air through the ductwork throughout your home. Now, a traditional, single-stage motor has essentially two “modes” – either it is moving air through the ducts at full blast, or it is completely off. Once the temperature reaches the thermostat’s set point and cycles off, the temperature may raise up to a few degrees before the air conditioner’s cooling stage kicks on again. And the process repeats. Not only does this create hot and cold spots in your home and tempt you to keep changing your thermostat settings, but also the constant cycling off and on consumes quite a bit of energy.
Teamwork – Two-Stage Motor
Another type of motor, the two-stage motor, differs from its single-stage cousin in one aspect – it has both a high speed and low speed setting. This means that the fan will only circulate the air at high speed when it is completely necessary (like when you have several guests in the house on a hot day), and will mostly use the low speed setting to maintain a more consistently cool environment. This eliminates some of the temperature swings that occur with a single-stage system, and also uses less electricity because it does not need to run at full speed as often.
Efficiency with Style – Variable Speed Motor
Introduced into the HVAC industry in recent years, variable speed motors have the ability to precisely control the airflow throughout your home in order to maintain your ideal indoor temperature. Some air conditioners, like the Lennox® XC25, can sense and adjust to temperature fluctuations down to ½ degree increments. Instead of only one or two stages, variable speed motors run at numerous stages, using only the exact fan speed and amount of electricity necessary to maintain the level of coolness you dialed into your thermostat.
This means that the motor is able to run continuously – never cycling on and off – all while consuming about 1/5 the electricity of a traditional single-stage air conditioner.*
Other Benefits of Variable Speed
Besides helping you save money on electricity, variable speed motors come with several other benefits. The first benefit is for allergy sufferers. The constant air circulation causes more air to move through your AC filter, allowing it to capture more airborne allergens like dander, dust, and so forth. (This benefit can be mimicked by single-stage air conditioners, albeit with higher electricity usage, by setting the fan to “ON” rather than “AUTO”, as discussed in this article.) Not to mention that the continual air circulation will have a positive impact on humidity control, as well. Also, the precise temperature control virtually eliminates hot and cold spots throughout your home, and the lack of temperature swings means that you won’t have to keep adjusting your thermostat. Finally, your air conditioner will be much quieter since the motor will very seldom need to operate at full blast.
Of course, it must be stated that variable speed air conditioners come with a higher initial price tag than single-stage or even two-stage systems. However, the long-term energy savings combined with the comfort benefits are, in many cases, more than enough to outweigh the initial investment. Plus, there are often rebates and convenient financing options available to you.
So, before you decide on your new air conditioner, be sure to find out what type of motor the unit has. Knowing the difference between single-stage, two-stage and variable speed motors will help you make an informed decision impacting the future of your home comfort.
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We’re here to help you decide on the best option for your home. Kobie Complete’s service area expands from Sarasota to Punta Gorda. Living in Sarasota and Charlotte County? Fill out the form below or call us at (941) 474-3691 to get a free, no-obligation quote on a new air conditioner installation.