How Does a Forced-Air Air Conditioner Work?
Your air conditioner is one of your most important resources during the summer, with your family depending upon it for comfort and safety once the temperatures start to rise. There are several different types of air conditioners, but most larger buildings, including houses and commercial ones, utilize the forced-air method.
In this article, we’ll discuss how a forced-air air conditioner works, including its basic components and a bit of the science behind it. We’ll also discuss some simple troubleshooting, as well as how to identify problems so that you know when to call a professional HVAC technician.
Air Conditioning: The Basics
The primary job of an air conditioner is to bring the temperature in a building down to a comfortable level, which it does by circulating cooled air. How does it cool the air down in the first place, though?
The technology behind air conditioners is actually very similar to another device you likely have in your home: your refrigerator. Both devices depend on a chemical refrigerant to do what they do. Refrigerant is a fluid with a low boiling point. Boiling point refers to the temperature at which the fluid will begin to boil—that is, transform into a vapor—and most refrigerants have a boiling point of around fifty degrees Fahrenheit.
The reason that fluid with a low boiling point is needed is that it will absorb heat energy. This means that as warm air passes over a coil containing the refrigerant, the fluid will begin to boil, absorbing the heat from the air. The heat energy can only be in one place at a time, so the air itself will begin to cool down dramatically. The now-cooled air can then be circulated throughout a building, bringing it to a comfortable temperature.
Choosing the Right Refrigerant Chemical
In the early days of air conditioning, any chemical with a low boiling point was used as a refrigerant. The problem with this is that many of these chemicals, such as ammonia, were highly toxic. Over the years, non-toxic alternatives were developed. However, it was discovered that many of these had a deleterious impact on the environment. Famously, refrigerant chemicals containing CFCs were found to be degrading the Earth’s ozone layer, so many of them had to be regulated.
Today, refrigerants with minimal climate impact are preferred and even required by law in most areas. The most popular choice today is a chemical in the propane family called R-290. Before installing an air conditioner in your home, you should ensure it utilizes R-290 and not a toxic or environmentally unsound refrigerant.
What Is Forced Air?
We’ve covered the science behind air conditioning itself, but how is the cooled air circulated throughout a building? Well, most structures utilize a forced-air air conditioner, which is a simple and relatively inexpensive way for air to be circulated after being cooled.
Hidden inside the structure of most buildings is a system of ductwork. These ducts are made from an inexpensive metal, such as aluminum, and insulated in order to prevent heat energy from leaking in or out. Each duct terminates at a vent, with usually one vent being in each room. On the other end of the ducts is a large, powerful fan that blows the cooled air through the ducts, ultimately venting the air into each room of the building.
How Does Your Air Conditioner Maintain the Right Temperature?
Another crucial component of a forced-air air conditioner is the thermostat: this is the mechanism that ensures your air conditioner can maintain the temperature that you desire. You simply set the thermostat to the temperature you desire, and the system then automatically turns the fan on and begins circulating cooled air when the room becomes too warm. Once the room reaches the correct temperature, the thermostat then alerts the system to shut off.
Modern air conditioners make use of smart thermostats, allowing you to have an even greater degree of control over the temperature control in your home. These thermostats can automatically adjust the temperature in a building based on a schedule; meaning that they can ensure the home remains at an optimal temperature even if you are asleep or not home.
Forced-air air conditioners are prone to a few problems that you should learn to watch out for. For example, constantly circulating air throughout a complex system of ducts will eventually cause dirt and grime to accumulate in them, ultimately reducing their effectiveness. If you notice that your air conditioner seems to be operating less efficiently—leading to a higher energy bill—you should first ensure that your ducts are thoroughly cleaned, as this is one of the main causes of sluggish HVAC systems.
A malfunctioning thermostat is also a common problem in a forced-air cooling system. If your AC unit cannot effectively tell what temperature it is supposed to be operating at, it will either run for too long or not long enough. Either case is bad since it will either drive your energy bill up or leave your building hot and uncomfortable.
When to Call a Professional
If there are problems with the mechanical or electrical parts in your air conditioner, you should contact an HVAC professional. In many cases, professional maintenance can solve the problem fairly quickly. You should also have regular check-ups performed on your HVAC system, even if nothing seems wrong. These systems can gradually lose efficiency over time if they’re not maintained, driving your energy bill up slowly but steadily. By having your air conditioner maintained regularly, you’ll save a great deal of money and potentially avoid costly repairs.
If you live in the Pacific Northwest, the best HVAC service you can get is from Entek. Specializing not only in forced-air air conditioners but in other cooling methods as well as heating and insulation, we can give your HVAC system the maintenance and repairs it needs to ensure a comfortable home for many summers to come.