The 3 Types of Air Conditioning Systems

by Tom Casey, America's Most Awarded Contractor

Like most things in our lives, technology has had dramatic impacts on the way we cool and heat our homes. In fact, with so many choices, it’s often confusing trying to figure out “what’s what” to be able to make an intelligent investment. A personalized approach to your comfort is crucial because it’s just as unique as you are.

The are (3) basic types of A/C systems:
Single-Stage
Two-Stage
Variable-Capacity

Each has its proper place in any neighborhood, based on our individual goals & objectives.

Single-Stage
Just as the name states, this type of system is either 100% “ON” or 100% “OFF”. These systems are more efficient (than existing systems) and contain many modern comfort & safety advances. They are sized for the MAX cooling load, so for a substantial number of hours every season they are actually “over-sized” and tend to short cycle (turn on/off more frequently). Often, indoor humidity is higher with these systems.

Two-Stage
Unlike the single-stage, a two-stage system can operate at “full load” OR “part load”. The LO-stage is normally 70% of the total capacity, while HI-stage is 100%. While two-stagers are also sized for MAX loads, they can automatically reduce capacity under “part-load” conditions, which are the vast majority of hours daily. Longer run times at reduced capacity translate directly into more even temperatures and lower indoor humidity levels. These systems have major technology upgrades, that also make them even more efficient, quieter, and self-diagnosing. 

Variable-Capacity
These are the most efficient systems you can buy for your home. They leverage all the latest & greatest technology, including Inverter Technology, that allows them to modulate from roughly 30% MIN capacity, all the way to 100%, and any place in-between based on ACTUAL indoor temperature and humidity conditions. These systems deliver optimal comfort and efficiency, perfectly matching capacity for virtually all different weather conditions. Variable-Capacity systems are like Cruise-Control for your home comfort. 

What Type of Homeowner Are You?
When you make home improvements to your home, do you usually do the cheapest thing you can, or the very best?
Single-Stage systems offer your lowest first cost, simple, basic “old-fashioned” on/off technology. Think of these as “code-compliant”; aka, the lowest standard allowed by law.
Two-Stage systems offer a middle-of-the-road initial investment, with upgraded technology and improved comfort. These are the modern homeowner’s new “standard”, the real value sweet spot.

Variable-Capacity systems are the top-of-the-line best, and have the highest initial investment, but also the biggest & fastest payback. These are for people who want the very best in terms of technology, efficiency, and comfort.