Introduction
It’s crucial that your air conditioner is blowing cold air this month—after all, July is the hottest month of the year in Missouri. With the temperature often reaching 90 degrees in July, Missouri lives up to its reputation, especially as the humidity sets in and the hot air becomes stifling. If you pour water on the concrete in July, chances are steam is going to rise from it. That’s Missouri in July for you.
Now, can you imagine having to deal with that while your air conditioner is not blowing cold air? Yikes! That is why in this blog post, we will discuss six reasons why your air conditioner is not blowing cold air.
Reason #1 – Your Thermostat Is Set Incorrectly
The first thing you should check if your air conditioner is not blowing cold air is the thermostat setting. Check to see if it is set to the cool setting. If it is not, set it to the cool setting and see if that resolves the issue.
If that doesn’t work, check to see if the temperature setting was recently changed. Adjust the thermostat to the desired temperature if it was.
If you find the issue is that your thermostat is not working even after troubleshooting, then most likely your system is experiencing other problems. In our blog post, “Thermostats 101,” we list some common problems with thermostats and how to fix them.
Reason #2 – Your Air Conditioner is Blowing Cold Air But The Registers Are Blocked
If your registers—covers on the air vents—are blocked, cold air won’t be able to flow through them. Registers can become blocked for several reasons: they may have been accidentally closed, furniture could be blocking them, a pet is currently lying on them, and more.
If you notice your HVAC AC is blowing cool air everywhere except in a specific room or area, check your registers. They may be blocked. If they are, remove any obstructions and open them up. If that solves the problem, great!
Reason #3 – You Have a Dirty Filter
If you haven’t changed your air filter in a while, a dirty air filter might be why your HVAC AC system isn’t blowing cold air. Over time, dirt and debris can collect on the air filter, creating a barrier that blocks air. This can result in your air conditioner not blowing cool air—or even any air at all.
If you can’t remember the last time you have changed your AC filter, it might be a good idea to replace it. Even if you’ve changed the filter within the last month or so, take a quick look at it. Sometimes filters collect more debris than usual. If it’s not dirty, then a clogged filter is probably not why your AC isn’t blowing cold air.
If your AC filter is dirty, consider whether there might be any reasons it is getting dirty more quickly. For example, if you live in a dusty environment or have pets, you may need to replace your air filter more often. Check your air filter; if it’s dirty, that’s likely the cause of the problem.
Reason #4 – Your Air Conditioner’s Evaporator Coil is Dirty
If your evaporator coil is dirty, your system will remove less heat from your home. While your HVAC AC may still blow air, the airflow will be weak, and the temperature will be inconsistent. Over time, if enough debris clogs your evaporator coil, its airflow will become restricted.
When the evaporator coil’s airflow becomes restricted, the coil will run colder and eventually freeze. If you think your evaporator coil has frozen, check for ice.
Here is the easiest way to check if your evaporator coil is frozen:
- Go outside where your outdoor AC unit, the condenser, is located.
- Look at the back or side of your condenser; you should see at least two pipes.
- The bigger pipe is your suction line and will likely have insulation wrapped around it. If you see ice formed on the suction line, then your evaporator coil is frozen.
- Do not try to remove the ice. Call an HVAC technician.
To avoid a dirty evaporator coil, make sure to have a reputable HVAC company maintain your HVAC system at least once a year.
Reason #5 – Your Air Conditioner is Low on Refrigerant
If your thermostat is set to its maximum cooling setting and you’re only getting lukewarm air, your HVAC system may be low on refrigerant.
Common reasons why your HVAC system may be low on refrigerant include a clogged filter, dirty coil, or a refrigerant leak. While a clogged filter and a dirty coil can typically be prevented with regular maintenance, a refrigerant leak is more difficult to address.
Refrigerant leaks can occur due to improper installation, wear and tear, corrosion, physical damage, or factory defects.
Signs that your system is low on refrigerant:
- Hearing a strange hissing or bubbling noise coming from your system.
- Ice buildup on your evaporator coil. However, it can occur due to other reasons, so do not take it as a sure sign your system is low on refrigerant.
- Ice buildup on your refrigerant lines. These insulated copper lines connect your HVAC units and transfer refrigerant between your outdoor and indoor units.
If you’ve done all the basic troubleshooting steps, such as changing your air filter and clearing debris from your system, and you still think your system has low refrigerant levels, it is time to call a professional HVAC technician.
Reason #6 – Your Air Conditioner’s Condenser Coil is Dirty
Another important coil in your system is the condenser coil. While the evaporator coil absorbs heat from your home, the condenser coil releases that heat outdoors.
If your condenser coil is dirty, your system will not run efficiently. A dirty condenser coil slows down the cooling process and leads to your HVAC system not getting rid of heat. When your system can’t get rid of heat, it won’t blow cold air.
If you notice any debris stuck between the fins of your outdoor unit where the condenser coil is contained, you will need to carefully remove it. You can use a garden hose (without a high-pressure nozzle) to gently rinse off the unit. Do not attempt to clean your outdoor unit when it is on.
Conclusion
In this blog post, we covered the six most common reasons why your AC is not blowing cold air. While there are other potential causes—such as a failed AC compressor, a faulty evaporator coil, or a damaged condenser coil—the reasons discussed here are the most common ones we’ve encountered. We also wanted to focus on the problems you can solve, and won’t put a huge dent in your wallet. As much as we enjoy our customer’s business, we are here to make sure your HVAC system runs as efficiently as it can for the longest time possible.
Is your AC not blowing cold air? Do you live in Jefferson County or the surrounding areas? If you answered yes to both of those questions, give us a call! We provide free estimates. Our phone number is 636-475-9384. Get your AC working again today.