What’s That Spooky Noise Coming From My A/C?

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Halloween is here, and with all the scary movies you’ve probably been watching, you might be a little spooked by the strange sounds coming from your air conditioning. Thankfully, there are no ghosts lurking in your a/c. Learn more about common noises in your a/c, what causes them, and how to fix them.

Hissing Sounds

If you hear a hissing sound from your a/c unit, it could be because the refrigerant is leaking. Refrigerant is a substance that transitions between liquid and gas phases and is essential to your a/c. It dehumidifies and cools indoor air by absorbing heat and releasing it outside. If refrigerant is leaking from your unit, your a/c may be unable to effectively cool your home. This means other parts of the a/c have to do more work, which makes those components wear out faster.

The refrigerant can be leaking from different parts of the unit, including the following:

  • Outdoor condenser unit: This is the part of the a/c with a fan located outside your house. If you hear the hissing noise from this unit, that means the refrigerant is leaking from the compressor, which changes the refrigerant into gas.
  • Heat pump: If your unit has a heat pump, the hissing sound is most likely coming from the reversal valve. This valve allows the pump to cool and heat your home.
  • Refrigerant line: There could be corrosion or a loose connection on a refrigerant line. Refrigerant lines are copper lines connecting the a/c’s indoor evaporator coil with the outdoor unit or heat pump.

Rattling Sounds

The cause of rattling sounds in your a/c is actually very simple—there might be a twig or small branch stuck in your unit. You can easily confirm this by checking your outdoor condenser unit to see if there is anything blocking the fan.

Grinding Sounds

There are a few reasons why your a/c might be making grinding sounds, including the following:

  • Blower fan belt: The blower fan belt helps the fan push air into your ducts. This might have come loose and is now rubbing against other components of the a/c.
  • Motor lubrication: The motor in your unit might require lubrication to run without making a grinding sound.
  • Compressor: Your compressor may have worn down, causing the pistons inside to make that grinding noise. This is the most common reason for grinding noises in your a/c.

How Do I Fix These Sounds?

It is important to get these problems fixed as soon as possible so that you can keep your home at a comfortable temperature, which is very important here in Florida. Neglecting to fix problems with your unit can increase your energy bills and create costly long-term issues with your unit. A professional can help diagnose the problem and deliver a solution.

A/C Designs has the expertise to help you address these spooky sounds. We are a leading a/c and heating company serving single-family homes and new builds in the Jacksonville, Florida area. Some of the services we offer include maintenance, repair, and new unit installation. Contact us today to learn more about how we can help you.

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