Why Is My Air Conditioner or AC working But Not Cooling the House? (Do THIS Now!)

It’s the hottest week of the summer, the temperature is over 90 degrees, and you’re constantly feeling the sweat trickle down your back. And for some reason, the AC is refusing to cool the room properly.


Sometimes, the AC will be running, and you’ll be hearing its murmur in the background of your day, but it won’t do any cooling. Let’s see why that happens and how you can fix it. The last video on this page has a special trick as well!

Why Is My AC Running But Not Cooling?

When your AC stops cooling the room, the first thing that comes to your mind is that there’s a malfunction somewhere. However, that’s not always the case. Instead, you may be simply overestimating your AC’s ability to handle the hot weather; let’s explore all reasons.

The Temperature Is too High

If your AC works perfectly well for most of the year and only stops cooling on the hottest days, that’s probably because it’s fine-tuned to your location. So, for example, if your area doesn’t usually get hotter than 90 degrees, the AC will be programmed to cool accordingly.

On the few days of the year that the temperature gets higher, you should expect a lower performance from the AC. There’s probably nothing that needs repairing.

It is also possible that you didn’t turn on the AC. We have discussed how you can turn on an AC without a remote here.

However, if the issue is ongoing for a good part of the summer, it might be a different reason.

You have the Wrong Size

If you’ve had the AC for several years and it’s been working fine, skip this reason. If you recently bought the AC, and it’s running but not cooling the room, you may want to recheck its power.

Each AC has a maximum number of BTUs (a measurement for cold air) it can generate per hour. And typically, larger rooms need more BTUs because there’s more space to cover.

So, if your AC’s maximum BTU output is less than the required for your room’s size, it’s probably the reason for the malfunction. As a rule of thumb, a 200-sqft room needs a 6000-BTU AC. The larger the room, the more power is needed.

There’s a Malfunction Somewhere

In most cases, the reason for the AC not cooling will be a malfunction somewhere. Here’s a brief

list of the defects that may be causing the issue:

-The air filter may be dirty due to all the dirt that enters through the air handler. Replacing a filter is often quite easy to do.

-The thermostat may not be adjusted to the cooling setting. This is a common mistake at the beginning of the summer. We have discussed how to adjust a thermostat here.

-The evaporator coil may be frozen. You’ll know that this is the case if there’s frost on the refrigerant tubing and if there’s a lot of condensate draining out.

-The condenser unit may be clogged as a result of the dirt accumulating between the fins. This issue may cause a complete shutdown in the cooling system after a while. The same can be true about the cold air inlet grille in your house. It is important to let an HVAC specialist maintain your system every year to avoid these issues.

-The refrigerant may be leaking, causing less cooling power overall. You will have to fix the hole and add more refrigerant. It is also possible that you have to top it off as refrigerant can evaporate.

-The heat pump may be malfunctioning because of a clogged coil or a refrigerant leak. Its air filter may also be blocked due to dirt.

How to Fix Air Conditioner Not Cooling?

If you did the necessary tests and made sure that the AC isn’t cooling because of a malfunction, it’ll be up to you to fix it. You can always hire a professional, but if you know your ways around ACs and want to save money, you can always fix it yourself.

Here’s how to fix a malfunctioning AC.

Install a New Air Filter

If your AC’s air filter is old enough, it may be time to change it altogether. Cleaning it may not do the trick, especially if the debris is too much.

On average, 1-inch filters may need replacements every 90 days, especially if you live in an area where dirt and debris are common. If you’re asthmatic or have any kind of allergy, it’s recommended to replace them monthly.

Defrost the Evaporator Coil

If your evaporator coil is frozen, it’ll cause the AC to consume more power yet generate less cool. So, the AC will be running, but it won’t be cooling your house. In this case, you can fix the issue by running the AC on its fan mode for a while, then checking the coil.

If the coil is still frozen, run it on the fan mode for longer. When it doesn’t have any more frost on it, you can turn the AC back on. Check the manual of your device to make sure that this is the right approach for your system.

Clean the Blocked Coils

As you probably already know, an AC has both an indoor and an outdoor unit. You may think you’re doing enough by maintaining the one inside, but the outdoor condenser is equally important. It’s even more important to clean and maintain because it’s more prone to dirt and debris.

Both the handler indoors and the condenser outdoors have coils. The condenser has coils to be able to take the heat outside. If your AC isn’t working properly, the coils may be clogged due to dirt and waste getting stuck inside. In this case, all it takes is a thorough clean, and the AC will work fine.

Fix the Refiregant Leak

If your AC is malfunctioning because of a refrigerant leak, the problem will need a professional worker to solve it. If the leak is happening due to a minor hole, the technician will likely patch it. However, this solution isn’t sustainable, and it’ll likely get punctured again if you overuse your AC.

If the problem is more significant, the technician will likely replace the coil altogether. It’ll be a bit costly, but leaving the AC to leak its refrigerant will get you higher utility bills. Plus, you’ll have to fix it one way or another, or else it’ll be rendered useless.

Closing Thoughts

Your AC is likely running but not cooling because some part of it is malfunctioning. It could be frozen coils, clogged air filters, or a leaking refrigerant. If all is fine, the problem is likely with the AC’s cooling settings, or the room is simply too big for it.

First, make sure you don’t open the room’s door constantly or overwork your AC, then start looking for the real reason behind the malfunction.