HVAC professional looking for Freon leak in air conditioner unit outside of home

Does Freon leak when the AC is off? First, Freon does not typically leak from air conditioners because air conditioning systems are closed. Freon cannot ordinarily escape, nor does it deplete with usage like the fuel in your car. The Freon in your air conditioner could theoretically last forever.

Even so, the likelihood of an air conditioner never sustaining a Freon leak over its lifetime is slim. Leaks occur when air conditioning systems sustain damage or wear and tear. The Freon in your air conditioner is pressurized. So yes, the Freon will continue to leak after you shut off your air conditioner.  

Freon is a brand name owned by DuPont for the refrigerant blend R22, but “Freon” is commonly used to refer to any refrigerant blend. Refrigerants are chemical compounds used in air conditioners, refrigerators, and humidifiers to remove heat and humidity. The refrigerant in your air conditioner continually cycles between a liquid and a gas as it absorbs heat from your home’s air and releases the heat outside. Without refrigerant, your air conditioner would not possess any cooling ability.

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Signs of an AC Freon Leak

Freon leaks exhibit telltale signs. It’s imperative to identify leaks early. Freon leaks can damage an air conditioning system and pose risks to your health and the environment.

Signs of an AC Freon Leak:

  • Loss of cooling power
  • Hissing and gurgling sounds
  • Frozen evaporator coil
  • High energy bills
  • Increased humidity
  • Strange smells

Loss of cooling power

Freon absorbs heat from the home’s air. When the Freon level is low due to a leak, the air conditioner has to work harder to cool it. It takes longer to cool the home, and the temperature might never reach the thermostat’s setting. Less cool or warm air blowing from the vents can indicate a Freon leak. You can quickly test the airflow by placing your hand in front of the vent.

Hissing and gurgling sounds

The Freon escaping through a crack or hole in the system is sometimes audible because the Freon in your air conditioner is a pressurized gas. Leaking Freon can make a hissing sound like air escaping from a popped tire. Large Freon leaks might make a wet, gurgling sound.

Freon flows through almost all of the air conditioner’s components. Hissing and gurgling sounds can come from the indoor unit, outdoor unit, or refrigeration lines that run between the units.

Frozen evaporator coil

Heat is absorbed from your home’s air when Freon flows through the copper tubing of the evaporator coil. The combination of cold refrigerant and warm air passing over the coil creates condensation. Usually, the condensation evaporates. A Freon leak reduces the amount of heat the refrigerant can absorb. The refrigerant gets colder than usual, and the condensation freezes instead of evaporating. Ice crystals form on the coils, and eventually, the system breaks down.

Freon leaks can also cause ice to form on the refrigerant lines. Check for frost on the lines outside the home that run from the house to the condenser to see if your AC is freezing up.

High energy bills

The loss of cooling power can result in high energy bills. The thermostat regulates a home’s temperature by turning the air conditioner on and off as needed. An air conditioner turns on more often and runs for extended periods when the airflow is low or warm air blows from the vents. The air conditioner’s increased energy usage will show up on your energy bill.

Increased humidity

Air conditioners remove humidity from your home in addition to removing heat. Typically, it takes about 15 minutes of runtime to begin dehumidifying a home. An air conditioner with a Freon leak is less efficient at cooling and removing humidity from the house.

Strange smells

Under some circumstances, you might smell the Freon leaking from your air conditioner. What does Freon smell like? Freon is generally odorless, but an odor may be detected in high concentrations. Freon smells differently to different people. It can have a sweet scent or smell like a chemical such as a nail polish remover, paint thinner, or chloroform.

What Causes AC Freon Leaks?

Freon leaks have some common causes:

  • Improper installation of the unit: The installer might have neglected to secure the unit’s components properly. Excessive vibrations can crack refrigerant lines.
  • Metal corrosion: Metal components can corrode over time due to chemical reactions or dog urine.
  • Factory defects: Some units are defective from the start. Units that never operate correctly eventually develop leaks.  
  • Wear and tear: Outdoor elements can cause rubber seals to wear out and metal to rust and corrode over time. Age is often a factor with Freon leaks.

Can Freon Leak in AC Be Fixed?

Freon leaks are repairable by licensed HVAC technicians. Refilling the Freon without first repairing the leak is pointless; the Freon will continue to leak until the leak’s cause is addressed. Furthermore, the EPA prohibits the sale of Freon to unlicensed persons. A professional technician will locate the leak’s source, repair it if possible, and refill the Freon.

Occasionally, Freon leaks damage other air conditioner parts. The evaporator coil, compressor, or entire unit might have to be replaced.

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Freon is not supposed to leak from an air conditioner. Freon levels only diminish if some part of the air conditioning system is damaged or worn out. However, Freon leaks are common. Air conditioners typically sustain a leak by the time they are 10 to 15 years old.

Freon is essential to your air conditioner’s operation. If your air conditioner has a Freon leak, you’ll likely notice a loss in cooling power, hissing and gurgling sounds, a frozen evaporator coil or refrigerant lines, high energy bills, increased humidity, or strange smells.

Turn off your air conditioner if you suspect a leak, and call an HVAC service immediately. Running the air conditioner with a leak can damage it. Because the system is pressurized, Freon will continue to leak from the air conditioner even when it’s off. A technician will inspect your system, repair leaks, and recharge the system with refrigerant.

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Did you know that Refrigeration Technologies (VIPER) has an indoor coil cleaner and Condensate Pan & Drain Cleaner that both have actual enzymes in them that kill the bacteria that cause odor? www.refrigtech.com

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