When it comes to your home, uneven heating and cooling can be a major nuisance to your comfort, and your wallet. A common way to spot if you have this problem is by walking around your house, if you notice that some rooms feel warmer or cooler, you have uneven temperatures in your house. Though it’s inconvenient, especially if external temperatures are unbearable, it’s a common issue that has many causes and solutions.

The efficiency and effectiveness of your HVAC system can be seen through routine maintenance. You invested a lot into your system, and by scheduling regular maintenance, you can extend its longevity and reap the benefits of having low energy costs, high-quality air, and a comfortable home.

Common causes of uneven heating and cooling range from simple issues you may be able to fix yourself, to more complex problems that require the help of an HVAC professional. When you do run into an issue you can fix on your own, it’s always important to do your research, and work slowly to ensure you’re making the right fixes. If you get in over your head, give us a call! We’re always here to help. To get started, here are a few problems that may arise with your system and the steps you can take to solve them:

Dirty Air Filters

Air filters are a vital component of your HVAC system, as they filter out pollen, dust, and other particles in the air before circulating them throughout your home. A clogged filter reduces the air that can flow through your system, forcing it to work harder for less than efficient results, and if left for too long, can cause your system to overheat and break down.

How to fix it:

Clean your air filter regularly, and when you notice damage or an excess of dirt, change it out for a new one. If your filter has a cardboard frame, these are meant to be disposed of after each use. If you have a permanent filter, follow these steps to clean it:

  1. To get started, turn your HVAC unit off for your safety.
  2. Take a look around your unit for a service panel and open it, the filter will be inside. Make sure you’ve checked all the vents, as some units have more than one filter.
  3. Take your filter(s) outside, and using a vacuum suck up as much dirt and debris as you can.
  4. Now that most of the loose dirt is gone, run your filter under warm water to remove any smaller particles. If it still looks dirty, mix equal parts warm water and vinegar and use a sponge to slowly remove anything left over.
  5. Leave your filter out to completely dry. While you’re waiting, clean off additional dirt and build-up on your system.

Leaking or Blocked Ductwork

The ductwork within your HVAC system is what distributes air throughout your home. Since it performs such a significant role, breakages and congestion are common and can occur for a number of reasons. It could be that one of your air vents is closed, blocked by furniture, or has just been poorly maintained. Regardless of how it happened, leaks and blockage in your ductwork waste energy and money, so it's important to identify this issue before it worsens.

How to fix it:

First, check that your vents are open and not blocked by furniture or curtains. If you still cannot identify the issue, schedule a maintenance appointment with a certified technician. Your system’s ductwork can be complex and you may not have the skills or tools to do it on your own, so it’s important to refer to a professional to inspect and fix the issue.

Open Windows and Air Drafts

It might sound obvious, but a window that was poorly installed, or is open even just a crack can cause hot or cool air to leak, affecting the internal temperatures of your home. You’d be surprised at all the different places that can let outside air into your home. To test for drafts, get your hand damp and run it along common problem areas for easy detection. From doors and window frames to electrical outlets and baseboards, there are many areas of your home worth checking.

How to fix it:

So, you’ve ensured your windows are closed tight, but now you’ve detected drafts in several problem areas. Depending upon the location, there are many air sealing techniques that can fix the issue, including caulking, weatherstripping, and adding spray insulation. Using each of these in tandem can ensure your house increases its ability to keep internal temperatures.

Caulk or weather stripping can be installed along your windows, doors, and baseboards to prevent air from leaking. If you notice cracks or holes around your windows, doors, exterior lights, or floors, consider using spray insulation to reach every nook and cranny.

If you’ve taken the steps to properly seal your home and you’re still experiencing uneven heating or cooling, call a professional to further inspect your home, and offer solutions.

Oversized or Undersized HVAC System Vents

Though it’s not as common, the reason you’re experiencing uneven cooling and heating may be due to the size of your system. If it’s not large enough for the size of your home, then it will not perform as efficiently, resulting in warmer or cooler areas of your house, and higher overall energy costs. On the other hand, a system that is too large can make your home reach preferred temperatures too quickly, and though this sounds ideal, it can cause your system to start and stop more frequently — also known as short cycling — leading to considerable damage.

How to fix it:

Have your system evaluated by a certified HVAC technician. They will check out your system and determine whether or not it's the right size for your home.

Oversized or Undersized Ductwork

As we mentioned, ductwork is a vital part of your system and has the huge responsibility of distributing air throughout your home. With that in mind, it’s important that your ductwork is properly sized for your home, and matched to your HVAC system's capacity.

Let’s say your ducts are too large. As your system begins to push air into them, air pressure will have a more difficult time building up due to the amount of excess space within the ducts. Without proper air pressure, your system's air flow decreases, leading to a less efficient system and higher energy costs as it works harder to provide results. On the other hand, if your ducts are too small, air pressure will increase due to the smaller space air is being pumped into, leading to increased noise and restricted airflow that is unevenly distributed.

How to fix it:

Contact a certified HVAC professional to perform an inspection. If this is the issue, you may have to replace your system’s ductwork.

Unbalanced Ductwork

Your ductwork system features a multitude of parts that distribute warm and cool air throughout your home, and having just one piece out of place can cause your system to become unbalanced, resulting in uneven heating and cooling. If you have unbalanced ductwork, this means that all the registers in your home have not been adjusted to optimize airflow.

How to fix it:

There are many causes for an unbalanced system, some of which you can fix on your own, but others will require the help of a professional. One way you may be able to fix your system is by adjusting the vents registers in the room that is experiencing issues. If the room is too hot or cold, close your vent diverters slightly and see if you experience any changes. If your room is not hot or cold enough, ensure your vent diverters are open and not obstructed by any furniture. If you are still experiencing issues, schedule an appointment with an HVAC professional.

Outdated HVAC System

If you’ve ruled out the issues above, it may be that your HVAC system has reached its expiry date, and it’s too old to function efficiently. If your furnace or boiler is more than 20 years old, or your AC unit is over 15 years old, the answer to your problems may be to update your system. Knowing the age of your HVAC system is important, as an aged-out system leads to frequent breakdowns, excessive dust in the air, worsened humidity, and, of course, uneven temperatures throughout your home.

How to fix it:

It’s time to invest in a new HVAC system. Schedule an appointment with your local certified HVAC company. They’ll come to your home to assess your current system, and determine a new one that will work best for your home's needs.

Take steps to prevent HVAC issues before they happen

Uneven home heating and cooling is usually the symptom of an ongoing problem. To prevent this issue from occurring, schedule maintenance twice a year to ensure the longevity and efficiency of your system. If you’re looking for comprehensive maintenance services, look no further than our Green Bow Service Plan, which provides total HVAC coverage and priority same-day appointments, without unexpected or hidden additional costs. When it comes to your HVAC system, don’t wait for issues to arise to schedule an appointment, your comfort is too important.

Learn how to choose the right HVAC company by reading our How to Choose an HVAC Company Blog.

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