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How To Tell if Your Air Conditioner Is Leaking Refrigerant


Refrigerant, also known as Freon, is a vital component of your cooling system. It’s a cooling agent that changes between its gaseous and liquid forms to cool your indoor air and keep your home comfortable. If there is less refrigerant in your system, the less likely it will be able to provide proper cooling for your home. Refrigerant leaks are no joke and should be dealt with immediately — your cooling system is a closed-loop system meaning refrigerant is meant to circulate throughout it without decreasing. However, it isn’t always easy to tell whether you have a Freon leak. To help you out, the pros at Mattioni have prepared a list of signs you might have an AC refrigerant leak.

1. Warm Air Blowing Out of Vents

If you notice lukewarm air is blowing out of your AC vents, first make sure your thermostat is not on “heat.” After that, make sure it is on “auto” and not “fan” — the fan setting allows air to blow through your vents even when your AC is not going through a cooling cycle. Next, make sure your air filter is clean. A blocked air filter might not allow your AC to perform to the best of its abilities. After you check all of this and you still notice warm air blowing through your vents, you might have a refrigerant leak.

2. Bubbling or Hissing Sounds

A bubbling or hissing sound from the refrigerant lines behind your outdoor condenser or from your indoor air handler is not a good sign. They are usually indicative of a refrigerant leak that needs to be taken care of immediately. Refrigerant is a harmful chemical so be sure not to touch the refrigerant lines in your cooling system — simply call an HVAC technician.

Hearing strange noises from the HVAC unit in your Pennsylvania-area home? Call Mattioni at 610-400-8510 to schedule repair services!

3. High Humidity Levels

When your AC cools your home, it also dehumidifies it. When it is unable to remove heat from your home due to lack of refrigerant, it will also be unable to remove humidity from it. If you notice humidity is higher indoors than usual, consult a professional because you might have refrigerant leak.

4. Frozen Evaporator Coil

During the cooling process, refrigerant usually passes through your indoor evaporator coil to absorb heat from the indoor air that blows over the coil. If you have low levels of refrigerant in your cooling system, there will not be enough refrigerant to absorb heating, leading to your evaporator coil freezing over. Frozen evaporator coils are important signs of low refrigerant — the moment you see ice collecting on your indoor coils, get in touch with your HVAC technician.

Do you notice any of these signs of an AC refrigerant leak? Contact the professionals at Mattioni! Our team of experts will be more than happy to repair the leak and reinstall refrigerant right away. Whether you have plumbing, heating, or air conditioning problems, Mattioni will be here to help. Call us today at 610-400-8510 or schedule service online!

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