Having the right amount of refrigerant is essential for proper AC performance. When your air conditioner is low on refrigerant, it won’t cool the way it’s supposed to.

And when the AC is completely out of refrigerant, it won’t cool at all.

Having a refrigerant leak or being out of refrigerant is serious – especially if it happens in the middle of the hot summer. Let’s take a look at the most common indicators for this problem. Here are a few signs your air conditioner is out of refrigerant or that it’s leaking refrigerant.

1. The air conditioner won’t cool

When the AC is out of refrigerant, it’s not going to cool your home. Full stop.

To understand why, consider how an air conditioner works. The heat inside your home is transferred to the refrigerant, which cycles through a coil and copper line set. Ultimately, the heat is expelled to the outdoors, leaving you with cool air inside your house.

Without the refrigerant, there’s no way to remove heat from your home. The system might turn on and run. There will be air coming out of the vents. But the air won’t be cold at all.


To be sure, an AC that’s not cooling isn’t always out of refrigerant. It could be a symptom of another problem, such as a bad capacitor, bad contactor, or bad control board.

But it is common for systems to lose some of all of their refrigerant via leaks in the AC’s evaporator coil. If yours isn’t cooling and you’ve confirmed it’s not a circuit breaker issue, it’s time to call your HVAC company to check on the unit.

2. You see ice on the air conditioner

This is a sign of low refrigerant. When it looks like your AC has frozen up and you see visible ice forming on it, there’s a very good chance you have a refrigerant leak.

The ice could be anywhere on the AC unit. You might notice ice on the outside of the outdoor unit or on the refrigerant line set itself. In severe cases, ice on the outdoor unit can become so thick that it damages system components.

Keep in mind that a heat pump unit that has a small layer of ice on it in winter isn’t necessarily a sign of a refrigerant leak. If the ice melts away after a few minutes, it actually means that your unit is working correctly.

Anyway, whenever you see ice on the unit, there’s a good chance the system is also struggling to cool your home. You may notice that you’re uncomfortable before you notice the ice.

Tip: If you see ice and haven’t changed your air filter in a really long time, do that right away! Then turn off the system and wait for the ice to melt.

Sometimes, a really dirty filter can block airflow through the system and cause ice to form on the AC. After the ice has melted and you’ve changed the filter, turn the AC back on and monitor its performance to see if you’ve solved the problem.

3. You’ve got sky high power bills

This is another possible indicator that the AC is low on refrigerant. During our hot Atlanta summers, air conditioners use more electricity than pretty much any other appliance. If your power bill seems unusually high – even for summer – it could be because the AC is leaking refrigerant and struggling to cool your home.

We’ve seen systems that were leaking refrigerant like crazy – missing as much as 2 lbs. in some cases – but the homeowners barely noticed the gradual reduction in indoor comfort. However, they did notice when they got a power bill reflecting the extreme amount of energy their AC was using.

4. The system cools fine most of the time but struggles on really hot days

Here’s a classic symptom of a slow refrigerant leak. Maybe the AC cools fine when it’s 78 to 83 degrees outside. But when temps rise to the high 80s or low 90s, all bets are off.

You’ll notice that the system runs all time, produces cool air, but never cools the house enough to satisfy the setting on your thermostat. If that’s what’s going on, call your HVAC company. They’ll check for a refrigerant leak.

5. High humidity is driving you nuts

We want to be careful with this one. There are lots of things that can cause your home to feel uncomfortably humid, such as an oversized air conditioning system, poor ductwork design, or lots of air leakage between your home and the outdoors.

But a refrigerant leak is definitely one possible reason for your high humidity problem, especially if it comes on suddenly. When you’ve been feeling comfortable but suddenly start experiencing a problem with high humidity, it’s probably time to call your HVAC company.

6. You notice an oil leak

An oil leak is a tell-tale sign of an AC that’s completely out of refrigerant. Most people notice their air conditioners aren’t cooling before they see the oil leak; however, it’s possible to notice the oil leak first if it happens during a time of year when you’re not using the AC or you’re only using it sporadically.

You’ll know you’re out of refrigerant when you see a lot of oil around the outdoor unit. Oil leaks and refrigerant leaks go hand in glove. When you see oil, you probably don’t have enough refrigerant in the system to cool your home. Your best course of action is to call your HVAC company right away.

Keep in mind that if the system has an oil leak (and, consequently, a refrigerant leak) and it’s out of warranty, the most cost-effective option is usually to replace the system.

Is your AC not working quite right? You might have a refrigerant leak.

If you’re experiencing any of the above signs your air conditioner is out of refrigerant (or low on refrigerant), it’s time to call your preferred HVAC contractor.

If you live in Metro Atlanta and have this issue, PV can help! Give us a call at (404) 994-2229 or fill out the form below to get in touch.

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