If you’re shopping for a new air conditioner this year… and you’ve been fortunate enough to find a good salesperson, who is passionate about their products, you will inevitably be asking “What is a 2 stage air conditioner?”
2 stage air conditioner
First of all, 2 stage air conditioners are not exactly new technology. The reality is that they’ve been around for years, though many people simply did not know they existed… or that they’ve been missing out all these years.
You see… a 2 stage air conditioner is in fact the “middle of the road” system these days. When people tell me they don’t want the lowest end, nor are they interested in the premium air conditioners… then I point them to the 2 stage air conditioner.
There are 3 types of air conditioners available (this goes for furnaces too but that’s another topic altogether): The single stage air conditioner, the 2 stage air conditioner, and the modulating (or multi-stage) air conditioner.
As you may have guessed, the single stage is the most basic of the three types. It is the type of air conditioner that most of us have had in our homes, if we’ve gad an air conditioner. I don’t want to take anything away from a single stage air conditioner, because they are very good in their own right… it’s just that they are limited in their ability to provide chilled, dehumidified air for all the days in our hot and sticky summer. The reason for this is that a single stage air conditioner only has one stage of operation… in other words, it can only run at one speed – Full Speed. So when it turns on, it runs at full speed, pulling heat out of the air at the fastest rate it can. this is great on +33C days with 95% humidity…. not so great on days when it’s +27C… not overly hot, but usually very humid, sticky, and darn right uncomfortable.
Dehumidifying happens as a byproduct of cooling. Warmer air can hold more vapor than colder air. So as the air cools, the vapor falls out of the air and the air is more dry.
On those +27C days, that single stage air conditioner is working at full speed when it only needs to work at 50% speed… What it does then, is that it removes heat at such a fast rate that… well here’s what happens: It’s hot and sticky in the house, so you decide to turn on the air conditioner. After about an hour the air conditioner turns off. It has cooled the house to the +23C on the thermostat. But it doesn’t feel like it’s +23C. It feels sticky and humid still… so you turn on the AC again by setting the inside temperature down to +21C. The air conditioner cycles on for another 45 minutes or so and then turns off. It has reached the +21C in the house. The issue is that +21C in the summer is god awful cold! Miserable!
So how do you fix that? With a 2 stage air conditioner of course.
A 2 stage air conditioner has a half speed that it can run… surprise, surprise! When the inside temperature is +27C, the air conditioner will run at half speed. It will cycle a lot of warm humid air through the system. It will remove the humidity from the air, but will not remove the heat at a fast rate. The end result is that you have cooled the air, dehumidified the air, but not made the inside of the house like the inside of a deep freezer! That 2 stage air conditioner still has full speed for the hot +33C days and can handle everything you throw at it (when sized correctly).
I hope you have learned a little about 2 stage air conditioners and that the next time you are shopping for a new system, you’ll consider the benefits of a 2 stage air conditioner.
By the way… Ever wondered why the top floor of your house is warm and uncomfortable while your air conditioner is running? And why you simply can’t keep the basement from freezing?
I have the answer. Click Here and Listen to my Radio Interview where I explain.