How Often Do You Need To Add Freon To Recharge An AC?

90% of the time, if there’s an issue with your AC, it’s electrical, and the other 10% of the time, it’s an issue with your refrigerant. Freon is a commonly used type of refrigerant in many air conditioners, and if the level gets too low, you’ll be stuck with an AC that doesn’t blow cold air.

This can make the summer months unbearable and leave you with a useless air conditioner. In this guide, we’ll explain how often you need to recharge home AC with Freon so you can keep it working properly.

How Often Do You Need To Add Freon To Your AC?

Your air conditioner needs refrigerant to function, and without it, you won’t be able to cool the air flowing through it. It works by absorbing the heat from the air, and as it gets hotter, it transitions from a gas to a liquid. As it cools down, it then transforms back into a gas so it can absorb more heat. This means your appliance can’t fulfill its function without refrigerant, and cold air won’t blow around your home.

Your refrigerant exists in a closed system within your evaporator. It will continue to travel around the copper coils throughout the life of the air conditioner, and your specific AC will be designed to have the exact right amount of Freon, so it will never need to be replaced. So, unlike fuel that’s used up, Freon will be usable forever if your AC is functioning properly.

The only time you will need to add Freon is if there’s an issue with the device and you notice the AC is low on refrigerant.

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Why Would An AC System Be Low On Freon?

Your AC system will be installed with a set amount of Freon so that it never needs to be topped up. Within the closed system, it should function indefinitely, but there are a few reasons why your air conditioner may not have enough refrigerant:


Leaks can occur in any part of your air conditioner, which can lead to Freon escaping. The most common points for leaks are the compressor, refrigerant coils, and the valve used to secure them. These can become damaged for a variety of reasons, and even a tiny crack can cause your refrigerant to leak. This will eventually deplete the Freon levels and stop the AC from running properly.

Old Age

As your AC gets older, it’s more likely to develop issues. Connections and seals can become worn, and wear and tear will have a significant impact. In old ACs, you’ll often find the Freon level has become too low because the gas has seeped out through a small gap or loose connection. This is sometimes a sign that you need to consider disposing your old AC and replacing your whole machine.


Regular maintenance of your HVAC system is advised, and having a professional examine the system every year can save you a fortune in unexpected repair costs. However, as your system is checked, a small amount of gas is likely to escape. The HVAC professional should replace anything lost, but if it’s trace amounts, then they may not notice. This won’t impact the machine immediately, but after several years of this maintenance, it can leave your Freon levels low.

How To Tell That Your Air Conditioner Is Low On Freon?

Freon levels should always remain consistent in a properly functioning AC, but you should still always be aware of the key signs that the refrigerant is running low:

Warm Air Blowing

Your AC is designed to draw hot air in, cool it, and then blow it back out into your home. If you find that the AC is turning on, but only blowing warm air, then it’s a sign that something inside isn’t operating as it should. This is probably happening because there isn’t enough Freon in the AC to cool the air properly.

Ice On The Refrigerant Line

If you notice a build-up of ice on the refrigerant line, it means that your evaporator coil is frozen solid within the AC, and the refrigerant is traveling back down through the copper tube. The Freon will then freeze any excess moisture in or around the tube and cause a build-up of ice. This is a sign that there’s too little refrigerant in the AC, and it needs to be topped up.

Hissing Sound From AC

If you notice a hissing or bubbling coming from your AC, it could be a sign that your Freon is low. This sound is usually caused by a small leak, often too small to see, so if you start to hear strange noises, you might want to get a professional to investigate.

Higher Energy Bills

If your Freon levels are too low, your AC will need to work harder to extract the heat from the air. This means it will run for longer and inflate your electricity bill. If you notice a spike in your energy bill, it’s worth checking the air conditioner because you may need more refrigerant.

How Much Will It Cost To Add Freon To Your Air Conditioner Unit?

If your AC is running low on Freon, then more will need to be added, or it can cause extreme damage to the unit. Adding more Freon isn’t always cheap, so it’s worth understanding the costs involved.

The potentially harmful nature of refrigerants makes them a hazard, and it’s illegal for anyone without specialist training to purchase or handle Freon. You will need to find an HVAC technician with specialist EPA approval to carry out the work. Not every HVAC professional will have this certification, so it pushes the costs up.

The cost of refrigerants varies because some are no longer produced, and their scarcity makes them a lot more expensive. Freon is roughly $50-$80 per pound, and a refill for most homeowners will cost $200-$400. Remember, it’s illegal for you to purchase Freon yourself, and you’ll have to buy it through your certified HVAC professional.

Given the environmental damage involved with leaking refrigerant, HVAC professionals are now no longer allowed to ‘top-up’ the Freon level, and they have to find and seal the leak. This means the total amount you’ll pay will vary depending on the exact nature of the issue. You should expect to pay $75-$200 for labor, pushing the overall cost up to $300-$600.

It’s really important that you find out which refrigerant your AC uses before you try to add more. If your air conditioner was built before 2010, it will likely use Freon, but more modern units may use Puron. Putting the wrong refrigerant in your AC can damage the mechanism or even cause combustion, but a professional will easily be able to determine which refrigerant is needed.

Refrigerant Charging for AC

People Also Ask (FAQ)

What happens when AC runs out of Freon?

Without Freon, the overall operation of the AC will be impacted. You won’t get any cold air, and if you run it for too long without a refrigerant, it can badly damage the mechanism.

Can I put Freon in my AC myself?

No, only technicians with an EPA 608 certification are legally allowed to buy and handle Freon.

How do I check my AC Freon level?

The easiest way to check if you need Freon is to go outside to your compressor and locate the thick copper cool line. Peel back the insulation and measure the temperature of the copper line with a thermometer. If it’s coming in at 50-60 degrees Fahrenheit, then your refrigerant is fine. If it’s any higher or lower, you have an issue.

A complete guide on how to check your exact Freon level can be found here:

What is considered the safest Freon?

Many refrigerants are harmful to the environment, so they have been phased out. R-22 (Freon) was the most common type of refrigerant used for years, but now R410A (sometimes known as Puron) is being used because it’s safer.


Freon operates in a closed system, so in a functioning AC, you should never need to add more. However, as your air conditioning system ages, you may start to see leaks appear, which deplete the Freon levels. When this happens, you’ll need to consult a certified HVAC technician who can safely handle refrigerants and make the necessary repairs to your air conditioner.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.