6 Signs You May Have an AC Refrigerant Leak

Conroy Baltimore
Written by Conroy Baltimore
Updated March 9, 2022
An AC on house backyard
Photo:-galinast / iStock / Getty Images Plus / Getty Images


  • Refrigerant enhances your AC cooling capacity.

  • Frozen coils, a warmer home, and higher electric bills can signal a refrigerant leak.

  • Leaks notwithstanding, the refrigerant in an AC unit should last 10 to 20 years.

  • Contacting a licensed professional is an ideal solution for handling leaks.

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Do you find yourself standing in front of the fan longer than usual during a hot summer day? Even your pet is panting more than expected because of the excess heat. For some reason, your home isn’t removing the hot air with its usual efficiency. A hotter home and a sweatier you could mean your AC is on the fritz

Specifically, it could be a sign of a refrigerant leak. Freon or refrigerant is essential for keeping your AC working and your home cool. Without it, your house can go from sanctuary to sauna in a heartbeat. 

The refrigerant in a standard AC unit should last 10 to 20 years. Your system should not lose more than a pound every few years or more; many systems go their entire life without needing the addition of gas. Suspect a leak? Watch out for these six signs so that you can nip freon leaks in the bud.

1. Warm Air Coming From Your Vents

First and foremost, let’s get the easiest troubleshooting idea out of the way. Is it possible someone may have accidentally switched the setting? You should also check if you have your AC set to “auto” rather than “fan.” The “fan” setting lets air blow through your vents even if your AC isn’t going through a cooling cycle.

If you’ve done multiple checks and the air isn’t as cold as it should be, you might have a refrigerant leak and should find local HVAC contractors to help you with the issue.

2. Frozen Evaporator Coil

Having a frozen evaporator coil is another tell-tale sign you might have a freon leak. Usually, the refrigerant passes through your indoor evaporator coil and removes heat from your air during the cooling process. Then, it blows that hot air over the coil to prevent freezing.

To check for freezing, locate your evaporator coils which are behind a removable access panel in your indoor unit. Make sure the AC is off before removing the panel. 

If you notice ice on your coil, get help from a licensed professional. If the problem is left to linger, you’ll have to pay between $600 to $2000 to replace your evaporator coil.

3. Loud Hissing Noises

No, that hissing sound is not an unwanted snake living in your vents (although we won’t fault you if you want to double-check). This noise can signal various problems with your AC, but it’s usually the sign of a refrigerant leak caused by cracks in your coils. 

Inspect your indoor or outdoor unit for problem areas. Larger cracks or holes may sound like something is bubbling, which indicates refrigerant leaking from your system.

4. Higher Electric Bills

Have you noticed a recent spike in your electricity bills? If so, you’ve probably been trying to counteract the humidity by lowering the thermostat temperature. Combatting hotter temperatures while facing a leak means your air conditioner will have to work twice as hard.  

The inefficiency in your cooling solution is why your electric bill isn’t at its usual rate. Take some time to review your statements from the same time last year. If there’s a noticeable difference, it might be time to repair your AC. 

5. Increased Indoor Humidity

A natural function of your air conditioner is to dehumidify your home. But a lack of cooling capacity means your AC will have a tougher time removing hot air from your home.

Discomfort aside, your house may also become a breeding ground for dangerous mold and mildew. Break out the cleaning supplies to address any problem areas and then enlist the help of an HVAC specialist for further diagnosis and repairs.

6. AC Leaking Water

Remember those frozen evaporator coils we mentioned earlier? Sometimes the ice might not be visible because it’s melted off. While you may confuse this for a refrigerant leak, it’s probably not. Instead, your AC might be leaking water (which is another problem you’ll have to tackle).

The drain pan underneath your system can overflow, causing water damage throughout your home. However, you’ll also need to be on the lookout for condensation line leaks, which can also stem from system inefficiency.

What to Do When There’s a Refrigerant Leak

If you’ve confirmed one or more of the signs above, you’ll want to address the issue right away. Refrigerant leaks may not seem like a big deal, and you may want to handle the issue on your own. However, this solution isn’t ideal because freon leaks can harm your health and cause health complications.

It’s best to seek a qualified heating and cooling specialist. Most pros charge between $50 to $150 per hour—and don’t forget to check your contractor’s references.

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