What Is Refrigerant and How Does It Help My Air Conditioner?

Written By Lester Mclaughlin
Updated On

Are you wondering what refrigerant is and how it helps your AC unit?

You’ve come to the right place!

In this Blue National HVAC guide, you’ll learn:

  • What refrigerant is
  • What happens when refrigerant levels are low
  • Why you shouldn’t recharge your air conditioner with refrigerant yourself

And much more!

What Is Refrigerant & How Does it Help AC

So, if you’re looking for answers about refrigerant and how it helps your air conditioner, keep reading our detailed guide below to get answers to all of your questions!

What Is A Refrigerant?

Refrigerant is a chemical compound that exists in a liquid or gaseous state in your air conditioning unit or heat pump(and refrigeration too). It plays a vital role in cooling your home, and without it, your air conditioning unit would not operate. 

How Does it Work in an Air Conditioner?

Your thermostat initiates the process of cooling your home by sensing the air temperature needs to be lowered, sending signals that kick on the air conditioning system components. 

The fan in the indoor unit draws in warm air from the home through the return air ducts, which then pass through filters that collect airborne particles like dust. 

Next, the indoor air moves over the cold evaporator coil, which contains cold, gaseous refrigerant. The heat from the indoor air is absorbed within the refrigerant, cooling the air as it moves over the coils. Your indoor unit’s blower then pushes the cool air through the air ducts into your home. 

The now warmer refrigerant gas exits your home through the refrigerant lines, traveling into the outdoor unit’s compressor.

The compressor pressurizes the refrigerant, turning it into a liquid, and sends it into the unit’s outdoor condenser coil. The outdoor fan sucks in outdoor air through the condenser coil, removing heat from the refrigerant and releasing it back outside. 

It then passes through the refrigerant lines on its way back to the indoor unit. But before it gets there, it first travels through the thermal expansion valve, increasing its pressure and cooling it. It also regulates the intake of refrigerant into the evaporator coils. 

The refrigerant then absorbs heat from indoor air again, and the cycle repeats. Think of your home as a large refrigeration system with the air conditioner refrigerating the entire home. After all, it is the same fundamental process as a refrigerator. 

There are several different types of refrigerants, but they are not interchangeable in your air conditioner. Your air conditioning system should have a sticker on the indoor or outdoor unit that indicates the proper refrigerant to use. 

Different Types of Refrigerant

There are three common types of AC refrigerants in residential air conditioners: R12, R22, and R410A. Your air conditioning unit may use one of these refrigerants, but your next-door neighbor’s AC unit could use another. 

Although they are all hydrocarbons, you cannot switch one type of refrigerant for another as most HVAC units are incompatible with different refrigerants. The main reason is that these common refrigerants all work at different pressures.

Chlorofluorocarbons (CFCs), like R12

Manufacturers have stopped using CFCs, which was common in older air conditioning units, as they contribute to the greenhouse gas effect and have a high ozone-depletion potential (ODP). Production of R12, which is a chlorofluorocarbon refrigerant halted in 1994.

Hydrochlorofluorocarbons (HCFCs), such as R22

This type of refrigerant, more commonly known as Freon, has been used as a refrigerant in air conditioning systems for many years. Freon has a detrimental effect on the environment, including the depletion of the ozone layer in the stratosphere, and a high global warming potential (GWP). 

Per the Clean Air Act, manufacturers have ceased using it in modern air conditioning units and are under a gradual phase-out. However, it is still common in older air conditioning units. New ones have to use R410A. 

Hydrofluorocarbons (HFCs), such as R410A

This form of refrigerant, also known as Puron, is a replacement for R22 refrigerant. The main difference is that chlorine is no longer included in the chemical concoction, making it less harmful to the environment. 

However, HFC refrigerants provide the same cooling effect as their predecessor. Systems that utilize R410A tend to provide optimal efficiency, and superior air quality, among other things. 

The EPA has initiated several rules regarding the use of refrigerants, including Puron, as it isn’t 100 percent safe. It is much better for the environment than the older types of refrigerant but is still ozone-depleting. As such, handling and disposal are still regulated. 

Violation of refrigerants’ regulations may lead to hefty fines from the EPA of up to $37,500 per day.

What Happens When The Refrigerant Levels Are Low?

Low refrigerant levels in your air conditioning unit can cause a host of issues. You may notice several different problems that hint towards low refrigerant levels in your air conditioning system. 

Refrigerant levels in the system should not need refilling, but if your system has sprung a leak in a single component, the levels may be lower than usual. 

Your Home Takes Longer To Cool

In the summer months, your air conditioner has to work overtime. If the refrigerant in the system is too low, your home will take much longer to cool off. 

Especially in the summer heat, your air conditioning unit will continuously struggle if it’s low on refrigerant but may never actually get your home to a comfortable, cool temperature. 

Frozen Evaporator Coils 

If you have low refrigerant levels, you may notice that ice has developed on the evaporator coils in your air conditioning unit. A refrigerant leak, which causes low refrigerant, can cause the formation of ice on the coils

This happens when the refrigerant seeps out of punctures in the coil. As the refrigerant exits the evaporator coils, it rapidly expands, which causes it to cool quickly. It then freezes on the coils, causing a buildup of ice. 

If you notice ice on your evaporator coils, don’t try to scrape it off. Since you have not repaired the leak, more refrigerant will leak. Instead, call our HVAC technicians to fix the leak, as doing so yourself could further damage the coils. 

Vents In Your Home Blow Warm Air

Low refrigerant levels can cause warmer than average air to circulate through your home. Your air conditioning unit does not function at optimal efficiency when refrigerant levels are low since the refrigerant is what helps cool the air as it moves through the system. 

This is apparent when the temperature differential between the supply and return air is too low. 

How Can You Tell When The AC Needs A Refrigerant Charge?

Your AC unit will exhibit several signs that indicate it needs a refrigerant charge. Perhaps the refrigerant leak is minor, and one recharge gets you through the sweltering summer, or it might be a significant leak that makes your unit lose charge quickly. 

Regardless of the severity, you need to have an HVAC contractor fix the leak to avoid repeating the cycle on an endless loop until the unit dies. Give us a call now if you need help. 

Spike In Energy Bills 

If your electric bill abruptly jumps, it may be a sign of low refrigerant. The lack of refrigerant causes the air conditioning unit to run constantly as it tries to reach the temperature setpoint on your thermostat. 

Since it is not running correctly and is continually cycling, you will notice an increase in your energy bill.

If your energy bill has spiked for no apparent reason and you have not made any other changes, have an HVAC technician check your air conditioning unit to ensure it runs at optimal efficiency.

Hissing or Bubbling Sound

For the most part, refrigerant leaks are small and therefore silent. However, more significant leaks may make a hissing or bubbling noise (during evaporation) while the air conditioning unit runs or even when it is off. 

If you notice this type of noise coming from the unit, you may have a leak. If you have a hunch that you have a leak, have one of our HVAC technicians come out to examine the unit.

There Aren’t Any Visible Issues

If your air conditioning unit is otherwise clean and functioning as it should, but blowing warm air and not exhibiting any of the other signs, it could still be a refrigerant leak. 

If you made sure the filter isn’t clogged, which is a common reason for AC units not cooling, you might have a refrigerant leak on your hands. 

Since the EPA has strict regulations regarding refrigerant leaks, you should seek the help of our professionals immediately. 

Should You Add A Refrigerant To Your AC By Yourself? Why Not?

You should not add refrigerant to your AC unit yourself. Not only is refrigerant not safe to handle, but you would also be breaking the law. Also, simply adding refrigerant to the unit will not fix the problem. 

It Isn’t Safe To Handle

According to the Environmental Protection Agency (EPA), refrigerants are unsafe, and only certified professionals should handle them. Refrigerants are harmful, putting you at risk of various health conditions. They are also flammable and cause ozone depletion. 

All refrigerants are denser than air, so they sink to the floor. If your AC unit leaks, it is likely that your children or small pets will experience the effects of refrigerant poisoning first since they’re closer to the floor. 

Moderate symptoms of refrigerant poisoning include:

  • Headaches
  • Vomiting
  • Nausea
  • Cough 
  • Irritation in the eyes, ears, and throat
  • Dizziness
  • Chemical burns on the skin or frostbite (usually from liquid refrigerant)

More severe symptoms may include:

  • Difficulty breathing
  • Irregular heart rate
  • Seizures
  • Loss of consciousness
  • A buildup of fluid of bleeding in the lungs
  • Vomiting blood

If you are suffering from any symptoms of refrigerant poisoning, move to a well-ventilated or outdoor area away from the leak. For lasting and severe symptoms, you may need hospital treatment.

Symptoms should go away once you go outside for a few minutes. However, if you are experiencing severe symptoms, seek medical attention immediately. 

Breaking The Law

Since the EPA requires a certified professional to complete the task of recharging refrigerant, you would be breaking the law if you did it yourself. Ensure that your HVAC technician has proper certification. 

The EPA has rigid rules regarding the handling and disposing of refrigerants. These rules include:

  • Purposefully causing refrigerant emissions outdoors is forbidden, and low-loss fittings are mandatory to mitigate the number of refrigerant leaks during connecting, purging, or disconnecting AC units. 
  • HVAC technicians must attempt to recover, recycle, and safely discard refrigerants.
  • You must rectify any refrigerant leak within 30 days. 
  • Any appliances that use refrigerant, including air conditioning units, must be discarded according to the EPA’s disposal guidelines.
  • Licensed HVAC companies and technicians are the only ones that may purchase refrigerants. 

Failing to abide by these rules may result in hefty fines and punishment from the EPA.

HVAC technicians who are EPA-certified are qualified to handle refrigerants safely. Refrigerants can be harmful to the environment when leaked. That is why you should have our certified HVAC technicians handle your leak quickly. 

Adding Refrigerant Isn’t Going To Repair The Issue

Air conditioning units should never need a refrigerant refill. If the levels dip below the designated amount, your unit likely has a leak that an HVAC technician should address. 

Simply topping off with new refrigerant in your AC unit may be a temporary fix, but it will not be a long-term fix as you haven’t dealt with the actual problem. You applied a bandaid instead of the cure. 

If you have a leak, the added refrigerant will continue to leak through the holes, leaving you at square one— another reason it’s best to enlist the help of our HVAC contractors who can isolate the problem. 

They will fix the leak and refill your refrigerant, helping to promote the health of your HVAC system in the long run. You should not try to complete this process yourself, as you may cause further damage to the unit, overfill and cause high pressure, leak more refrigerant to the environment, or injure yourself.

How Can A HVAC Contractor Help?

Recruiting our licensed HVAC contractors is the best thing to do when it comes to the refrigerant in your air conditioning unit. You should not attempt to fix a leak or recharge your unit, as you will be violating strict laws surrounding refrigerants. Plus, it is not safe to handle.

If you suspect your air conditioning unit leaks or if it just isn’t working at optimal efficiency, call our HVAC pros today. All of our technicians are well versed in the EPA’s rules and can fix the leak and recharge your unit quickly.

Meet Your HVAC Expert

Lester Mclaughlin

HVAC systems are highly technical and often is the most misunderstood part of the house. From ductwork to heat pumps, I've been exposed to all sorts of issues facing homeowners. It really irks me when a homeowner is given bad advice like refilling freon vs fixing a leak in the system. I'm here to help our website readers with their heating and a/c problems.
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