If the airflow from your HVAC ducts has become weak, you may start to notice cold spots in your home or certain rooms that don’t seem to jive with your heating and cooling system. For example, in one area you may feel like snuggling with a blanket, while in another you may start to sweat.
Sometimes such inconveniences can be easy to ignore, especially if you don’t frequent an affected area. However, it’s important to get to the bottom of the issue to prevent more serious problems in the future. Step one in addressing weak airflow from your HVAC ducts is to determine the cause of the problem.
In this post, cooling and furnace installation expert Bill Reynolds Heating & Air Conditioning lists some of the most common culprits behind low airflow.
Leaks. Leaks are among the first things that HVAC professionals look for when determining the cause of low airflow. In many cases, the problem lies in the small holes and cracks that can be found in the duct system. Because of these openings, air begins to leak, causing a drop in air pressure and making it hard for air to move through the system. You can tape the small openings as a temporary fix, then have a professional patch up the problem areas. If your ducts are already too damaged, it’s possible that you’ll need new ducts.
Dirty or blocked ducts. Although air filters are capable of keeping dust and dirt out of your HVAC system, there’s a limit to their functionality. Some particles will still get through and stick to the ducts due to moisture or static pressure. Over time, these small particles will accumulate and cause airflow and air quality problems. To prevent such issues, make sure to have your ducts cleaned by a professional. Do this on a regular basis so as to avoid dirt and dust buildup in your duct system.
Closed or blocked vents. Air must be able to enter and disperse freely in order to heat or cool your home. It’s pumped through the vents in the room, so if your vents are blocked or closed, there’s no way for air to flow properly into the intended spaces. HVAC professionals, including air conditioner repair experts, usually check for anything that could be obstructing the vents, such as furniture or bedding. Sometimes, though, the dampers on the vents are accidentally closed, so airflow is blocked. Once you’ve identified the cause of the obstruction, make sure to clear the vents and try to feel if the airflow has returned.
Closed damper valve. Dampers are among the primary flow regulators in your heating and cooling system. They can direct airflow or completely put a stop to it, so if an area in your home needs more air, dampers can block off or open paths that will make it easier for the air to reach the space.
The dampers can be automatically controlled by your thermostat. If you do have an automatic damper system, you might want to check to see if the dampers are stuck. However, this might be more of an electrical problem. Since the thermostat will continue to change the position of the dampers automatically, it would be too much of a hassle to manually adjust them.
In the case of manual dampers, the problem could be as simple as being unintentionally left in the wrong position. You can check if they’re in the correct position by locating them in your ductwork.
Damaged or disconnected duct runs. Each duct run in a home is supposed to be designed and installed in such a way that it can effectively deliver a certain amount of air to a particular space in your home. Any changes in the configuration of your ductwork can affect its ability to deliver the correct amount of air.
If your ductwork has been incorrectly installed, airflow can easily be restricted. Furthermore, if the air has to travel further and take more turns and bends, more turbulence is created. This often leads to the failure of the air to reach the room where it’s intended to go. That said, watch out for a crushed run or a bent or kinked piece of flex because this might be what’s causing the weak airflow in your home.
Undersized vents or oversized ductwork. Having the correct static pressure is essential for air to be able to move through the ductwork. If the ductwork is too big, the pressure will naturally drop, and the air will never reach its destination. The more common problem, though, is ductwork that’s too small, which can cause restrictions to the point that the proper amount of airflow doesn’t reach the intended location.
Restrictive air filters. When air is pulled through the return vent, it needs to pass through a filter to remove dust, dirt, allergens and other contaminants. These filters usually have a MERV (minimum efficiency reporting value) rating, which is based on how finely they can filter the air. A higher MERV rating means that the filter can filter out finer particles. This is certainly a good thing, but when these fine particles combine with the dust and dirt that have accumulated on the filter, you might end up with a clogged filter that doesn’t allow enough air to pass through.
You can opt to use less fine filters so that they won’t clog as easily, or you can simply clean or replace the filter on a regular basis. Make sure that you don’t ignore any issues with your air filter, because these could ultimately affect your entire HVAC system. Without sufficient air to heat or cool your home, your HVAC system will naturally have to work harder to pump out the required amount of heat or cold air.
A Few Reminders
As you may have noticed, there are many possible reasons for weak airflow. Figuring out the main culprit all by yourself could be difficult, so you might as well get the help of an HVAC professional. This will allow you to be certain about the issues in your HVAC system, and ultimately enable you to apply the right solution to the problem.
With their expertise, HVAC contractors can help you determine the immediate cause of the problem and investigate further so as to determine other problems in your HVAC system that may also have been contributing to the weak airflow problem. For instance, if your ducts have small holes or cracks, they can help you figure out why these openings have formed so that you can prevent them in the future.
Lastly, don’t attempt to fix your ducts or vents on your own, as you may only cause further damage. Leave the job to professionals to ensure a permanent or long-lasting fix.
Bill Reynolds Heating & Air Conditioning has been serving local customers since 1958. We always ensure quality service at fair prices, so you can count on us to provide value for your money. Along with cooling and heating services, we also have expertise in boilers, heat pumps, indoor air quality, plumbing and more. Call us at (440) 946-7863 or fill out our contact form to request a quote.