Is Upgrading Your AC to a Variable-Speed Air Conditioner Worth It?

Published by Parisa Ostovari

“What is a variable-speed air conditioner?” That’s a common question we hear from homeowners who are looking to either replace or upgrade their air conditioner or entire HVAC system. A variable-speed compressor is an advanced technology that allows HVAC systems to provide optimal efficiency and comfort indoors.

In order to know whether a variable-speed AC is a good fit for you home, it’s helpful to have a basic understanding of the three types of air compressors: single-stage, two-stage and variable-speed.

What Is a Single-Stage AC?

Most homes with central air conditioning use a single-stage compressor. This type of compressor runs at maximum capacity no matter how much or little cooling you need and turns on and off continuously throughout the day.

For example, if your thermostat is set to 75 degrees, the AC will turn on anytime the indoor temperature reaches 76 degrees or higher. Once the AC has cooled the indoor temperature back down to 75 degrees it will turn off. Because maintaining a stable indoor temperature rarely requires the air conditioner to work at full blast, a lot of energy goes to waste.

What Is a Two-Stage AC?

A two-stage compressor can run on a high- or a low-speed setting. Because the low setting is usually enough to keep your temperature stable, this compressor can save you energy by running at a slower speed more often. It kicks into the high setting only when your cooling demand is great enough to require a large amount of cool air quickly.

What Is a Variable-Speed AC?

A variable-speed air conditioner isn’t restricted to specific settings; it blows a smooth, steady stream of cold air through your home to maintain the desired indoor temperature. This method allows the compressor to choose the precise speed that’s most efficient for the given cooling demand. You’ll enjoy optimal energy efficiency along with a more stable and even temperature.

Benefits of a Variable-Speed Air Conditioner

Improved comfort and efficiency are the two biggest benefits of a variable-speed air conditioner. Indoor comfort is improved because the compressor’s continuous run time helps dehumidify your home more effectively. Relative humidity inside your home increases when the AC isn’t on. Since a single-stage AC doesn’t run continuously, it can be harder for some homeowners to achieve a comfortable indoor temperature when it’s 95 degrees outside.

The other big benefit is efficiency. Because variable-speed air conditioners don’t turn on as frequently, they have lower utility costs. Most of your AC’s electricity draw happens when it turns on – not while it’s running. The constant turning on and off (otherwise known as short cycling) of your air conditioner uses more electricity and is less energy-efficient.

Since variable-speed units run more frequently, they are also quieter and filter the indoor air more effectively.

Is a Variable Speed AC Worth It?

Two-stage and variable-speed air conditioners are more expensive than single-stage systems. With that in mind, it’s important to make sure you weigh all of your options and determine what type of system not only fits your budget, but also fits your home comfort needs.

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