A wide variety of factors go into determining how well an HVAC system works and how energy efficient it is. This includes things like the size and type of the HVAC equipment as well as the age of the system and if it’s kept properly maintained. Another essential factor is whether the system is properly air balanced so that the air it puts out gets distributed evenly across the building. This article will explain all you should know about air balancing and how to determine if your HVAC system is balanced properly.
Why Air Balancing Matters
The purpose of air balancing is to ensure that the HVAC system heats and cools every floor and every room in the building evenly. That way the temperature mostly stays the same across the entire building. If your HVAC system isn’t properly balanced, some parts of the building may often receive more hot or cool air than necessary while other rooms may have insufficient airflow.
Air balancing is also essential for ensuring the HVAC system works as efficiently as possible to keep your heating and cooling bills at a minimum. Without proper balancing, the central area of the building where the thermostat is located could often be warmer than the rest of it in the summer or cooler in the winter. As a result, the HVAC system will cycle on more than it really needs to. Each heating or cooling cycle may also last longer than necessary as a result of the thermostat sensing that the building is warmer or cooler than it actually is. This means your energy bills will be higher than they would be if the system had proper air balancing.
Air balancing can also make a fairly significant difference in how long an HVAC system lasts and how likely it is to break down and require various repairs. That’s again because the system will have to work harder to heat or cool the house, resulting in more yearly wear and tear on its components.
Critical Factors in Proper Air Balancing
Air balancing is something that should always be done when installing a new HVAC system or replacing existing cooling or heating units. Part of the process involves adjusting the blower as needed to make sure it runs at the right speed and circulates the correct volume of air. If the blower runs at too high a speed, the system won’t heat or cool as effectively as it should. That’s because the incoming air will move through the furnace or AC air handler too quickly, resulting it in not getting fully heated or cooled before it flows out into the supply ductwork. The system also won’t heat or cool as well if the blower runs too slowly. Nonetheless, the bigger issue in this case is that it can lead to frequent issues like the furnace overheating or the AC evaporator coil freezing up.
The most important part of air balancing involves the design and layout of the ductwork system and all of the supply and return air vents. Two of the most crucial factors for ensuring proper air balancing are the location of the return air vents and the size of the return air ductwork. The return air vents and ductwork are where the incoming air gets drawn into the HVAC system.
If the return ductwork is too small, there won’t be enough air coming in to supply the entire house with heating or cooling. That means the airflow coming out of the supply vents in the rooms furthest away from the furnace and air handler will be fairly weak, resulting in those rooms usually staying warmer or cooler than you want.
The location of the return air vents matters for ensuring the system can effectively circulate air throughout the entire house. Ideally, these vents will be centrally located in an area like a hallway and not too close to any supply vents. They’re usually also fairly close to the thermostat. Homes with only a basement and ground floor often just have one or two return air vents on the ground floor. Homes with three or more stories will typically have return air vents on at least two of the floors, as this helps to ensure that each floor gets evenly heated and cooled.
The size and layout of the supply ducts are also key for ensuring the conditioned air flows smoothly and encounters as little resistance as possible. If the supply ductwork is too large, it makes it much more difficult for the blower to move air into each room. If the ductwork is too small, it creates an issue with the static pressure being too high. That means there is more airflow resistance within the duct system and the blower has to work much harder to move air through the ducts.
How Professionals Test Air Balancing
In addition to inspecting the ductwork system and checking the speed of the blower, professional AC and heating maintenance technicians also use various methods to test things like the static pressure and the volume of airflow. This often involves just measuring the airflow coming out of each supply vent to make sure that the air is being evenly distributed throughout the house. They may also measure the temperature of the air coming out of vents in different parts of the house. This also alerts them to check for issues like ductwork leaks that can contribute to poor performance and decreased energy efficiency.
Many HVAC systems have balancing dampers where some or all of the branch ducts connect to the main supply duct, also known as the trunk. These dampers can be adjusted by partially opening or closing them to control the volume of air flowing into any of the branch ducts. After measuring the airflow coming out of each vent, the technician can then adjust certain dampers until there is an even volume of air coming out of all the vents.
How to Know When Air Balancing Is Necessary
An experienced HVAC company will always make sure to perform all of the necessary air balancing steps and checks when installing a new system. Nonetheless, it’s somewhat common for an older system to develop issues that lead to the airflow no longer being properly balanced. Renovating parts of a house or putting an addition on will also almost always throw the balance off.
The good news is that there are usually some fairly obvious signs that you need to have the air balancing in your HVAC system checked and readjusted. One is if the airflow in certain rooms is much weaker than in the others. This issue is especially common in the rooms at the end of a branch duct or the rooms that are farthest from the furnace and air handler. Hot and cold spots in parts of a house also often indicate the HVAC system isn’t properly balanced and that it’s not cooling or heating evenly. If this is the case, call for AC maintenance or a heating tune-up so a professional can make adjustments.
If you don’t think your HVAC system is performing as well as it should, one thing you can do is use a thermometer to measure the temperature on different floors and in different parts of the house. It’s common for there to be slight differences in temperature in different areas. However, a temperature difference of more than two or three degrees between one floor and another or on opposite sides of the house is a fairly certain sign your HVAC system isn’t properly balanced.
As one of the leading HVAC companies in Las Vegas, Polar Air & Heating, Inc. can expertly manage all of your home comfort needs. Whether it’s air balancing, repairs, maintenance, or installation, our team of certified technicians can handle it all. Contact us today to schedule an inspection or service call.
