Why Is My AC Making a Loud Noise?

When Starting or Shutting Off

Count on the HVAC Experts in Southwest Florida

Living in Southwest Florida can have its perks, but sometimes the temperature and humidity rise, making your air-conditioned home your one place of shelter from the heat. Your air conditioner is essential for the summer months and for the majority of the year in Florida. That’s why at the first signs of trouble, you need the help of a qualified HVAC technician from BHS. Air conditioners rarely quit without any warning signs, which means you have to be on the lookout for any indicators that things are amiss. You can’t ignore strange noises or other occurrences that are out of the ordinary. That being said, it can be difficult to know what signs your air conditioner is sending you, but fortunately, we’re here to help. Just know that any loud noise is not normal, especially with modern units. So, if you hear anything loud, it’s time to call us. We’ve also developed a guide to help you identify what might be wrong with your unit. Read on to translate the language of your AC and get a jump on repairs before things become worse.

High-Pitched Whistling or Screaming

If you a hear a noise like this, do not delay in calling a professional HVAC technician. This is one of the most serious signs your AC unit can send you, as it could be a potentially dangerous situation. This sound indicates one of two things: either there is a refrigerant leak or there is an issue with the compressor, causing high internal pressure build-up. Most air conditioners have certain safety features that should shut the unit off in situations like these, but that is not always the case. If you hear a screaming noise, be sure to turn off the unit immediately and do not turn it back on until it’s been inspected by an HVAC repair company.

Deep Banging or Clanging from the Outside Unit

These sounds can indicate a number of problems with your unit, the simplest of which is that a piece of debris, like a stick, has fallen into the unit and the fan is hitting it. This is a quick fix as long as the debris can be removed safely. While some homeowners do this themselves (after turning off the unit), if you are unsure about it, call a professional, as that is the safest way to get it done. A banging noise can also point to a more serious issue in that there may be a loose or broken part inside the compressor or an unbalanced blower motor. It could also indicate that the entire compressor itself is loose, which would require a replacement.

Metal-on-Metal Screeching

When the air conditioner turns on, if you hear a loud metal-on-metal screeching sound coming from the outdoor unit, you likely need HVAC service from a Southwest Florida contractor. This sound usually occurs throughout the entire AC cycle and indicates that the bearings of your fan motor are bad. Be sure to call a professional right away as this means you need to replace your fan motor.

Regular Squealing from Inside of the Unit

The most likely cause of a squealing noise from your unit is a misaligned or worn fan belt. Though the sound may come and go as temps cause the belt to expand and contract, this still indicates your belt needs attention. You can continue to run your unit, but you should call a professional, as the belt could break at any moment, leaving you without AC. A squealing noise can also be a sign that the outdoor fan motor or indoor blower motor may be going bad or malfunctioning. This repair will require the help of an HVAC professional, so call one right away.

Rattling from the Outdoor Unit

There is no way to completely prevent the deterioration of an AC unit. Just as with any other piece of equipment, aging will begin to show its signs. A rattling sign most often is a sign that age is taking its toll on your unit, loosening parts that vibrate and make noise as the unit runs. But rattling can also be caused by several other things, including twigs or leaves stuck inside the unit, a loose fan, or a malfunctioning electrical contractor. All of these can cause larger problems if left too long, so be sure to have someone take a look at it right away.

Constant Humming

Generally, a humming sound from your AC unit isn’t a cause for too much concern, at least not immediately. Humming can be caused by loose parts or refrigerant piping resulting in audible vibration. While this isn’t something that requires attention right at the moment, it isn’t something you should leave unchecked either, as it can lead to more severe problems down the road. When you hear humming and the compressor will not start, you could be facing an issue with the motor. Your best bet is to have a professional take a look, even if it doesn’t sound too serious. An HVAC technician can identify the problem and make sure it gets taken care of.

Metal Popping

This sound is the one to be least concerned about, as it is usually just the ductwork responding to the unit turning on or off. As the temperature changes, the metal of the ductwork can contract or expand, resulting in those popping sounds you’ve been hearing. This process isn’t hurting your system in any way, but you can use some type of insulation or foam to help reduce the noise.

Contact Us today to have your AC examined by a professional!

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