Home Improvement

How to Tell When Your Heating and Cooling System is Working Properly


You wake up in the middle of the night drenched in a puddle of sweat. When you check the thermostat, the temperature in your home is outrageous. Apparently, the AC never decided to kick on. 

There might be something wrong with your heating and cooling system. Before you hire someone to come out and make repairs, it’s not a bad idea to run a few tests. 

It’s not difficult to do and only takes a few minutes. All you need is a thermometer and a few sheets of toilet paper. Check out this guide to learn how to find out if your HVAC unit is on the fritz. 

Signs Your Heating and Cooling System Is Going Out

Before we talk about how to check your central heating and cooling system for issues, you should learn what warrants the alarm. You would feel silly if you called an HVAC replacement company for a problem that was caused by a dirty air filter. 

Bad Odors 

There’s a horrible smell going on in your home. No matter how many candles you light, nothing can cancel it out. Upon tracking the source, you discover that it’s your HVAC system. 

Bad odors aren’t an uncommon problem. It means that moisture was allowed to build up in your ducts. This moisture caused mold to grow, which resulted in that musty smell. 

The best way to kick the odor to the curb is by calling a professional duct cleaning service. They’ll use the power of ultraviolet light to stop any growth in its tracks. 

Strange Sounds 

It’s not unusual for your HVAC system to cause a little ruckus when it turns on and off. It shouldn’t be so loud that it ruins an evening of TV watching, though. 

If you hear any rattling or buzzing, that’s a good indicator that you’ve got a loose part roaming around inside the system. Whistling and grinding are a sign of an even bigger issue. 

Water Leaks

You’re walking through your home in the middle of the night when you step in a puddle. If the water is located around your AC unit, that’s a sign that you have a leak on your hands. 

Granted, it’s not unusual for your system to gather up a little condensation while it runs. It shouldn’t be enough to cause a puddle to form, however. 

High Humidity 

During the spring and summer, you’re bound to feel some humidity. That doesn’t mean that you should feel hot and sticky while sitting in your home. 

It’s the job of your geothermal heating and cooling system to regulate the humidity levels in your home. If it can’t keep up, you may want to call a repair company. 

It Cycles Too Often 

Throughout the day, you’ll hear your AC unit turn on and run for a bit before turning off again. This is your unit doing its regularly scheduled cooling routine. 

As you can imagine, it’s going to do this song and dance a lot more often in the summer to compete with the rising temperatures outdoors. This being said, it shouldn’t be cycling on every few minutes. 

Test Your System

In the case of some of the issues above, you may want to call someone out to look at your unit right away. In other cases, however, it may be a better idea to make sure your system is running properly before you pay for a repair company. 

There’s a simple test that you can do to learn for sure if your system is on the fritz. Grab a piece of tissue paper and a thermometer, and let’s get started. 

Get Your System Ready for the Test

The first step is to get your heating and cooling systems ready for the test. Things such as a dirty filter will cause an airflow restriction, which can be the root of many of the problems we discussed above. 

You want to rule that out as an issue before running the test. Remove your vent cover and take a look at the filter. If it looks a little worse for wear, change it out. 

Locate Your Supply and Return Ducts

Once you’ve changed out the dirty filter, grab your tissue paper and hold it up to every duct in your home. If it’s a supply duct, your tissue paper will blow out. If it’s a return duct, it will suck the paper in. 

After you’ve figured out which ducts are which, it’s time to do the actual test. Turn on your AC as low as you comfortably can and let it run for a few minutes. 

Grab a Thermometer 

Go to the nearest supply air duct in your indoor unit and tape your thermometer to the side of it. After about ten minutes, you’re free to record the reading and remove the thermometer. 

Head to your nearest return air duct and do the same thing. You’re now going to subtract the numbers from each other. The result will tell you if there is indeed something wrong with your system. 

Reading the Results

When subtracting the numbers, you should only see a difference of 20 or so. If it’s any less or more than that, there’s a good chance that your unit has a problem. 

Get Your Heating and Cooling Under Control

The last thing you want is for your heating and cooling system to stop working in the middle of the night. It’s never fun to wake up shivering or in a puddle of sweat. 

Stay on top of things by testing your unit regularly. Doing so will allow you to spot potential problems before they get too out of hand. For additional house repair tips that will help you keep your place in tip-top shape, visit the Home Improvement section of our blog. 

Hemant Kumar
Hemant Kumar is a project manager at Tridindia with more than nine years of commendable experience in writing about LMS, translation, and IT. His unmatched talent and passion for digital marketing gave him the opportunity to work as a multi-tasking project manager at TridIndia’s sister company, Link Building Corp. Today, he contributes to the world by imparting knowledge on SEO, link building and internet marketing etc., that helps business owners grow their online business.