Why Is My HVAC System So Loud?

fotex2020-09-30T12:20:06-07:00September 30th, 2020|HVAC Blog|

Do you notice a squealing or rattling coming from your air conditioning unit? You may be wondering why your HVAC system is so loud. There are many different possibilities, and we’ll help you try and identify the problem! Luckily, most HVAC systems are very reliable as long as they’ve been routinely maintained or aren’t overdue for a replacement.

Unusual Sounds

  • If you have an outdoor unit and notice a loud rattle or clattering, it means a small piece of debris may have got into the compressor fan. Although there is a gate to protect against this, small twigs or other debris can make their way inside occasionally. You will want to turn off the unit and remove any visible obstructions. Check for any visible damage to the coils, compressor, or fan. If you see any, you’ll want to call an HVAC professional.
  • Squealing can indicate a worn down belt.
  • If you hear a loud banging, you should shut off the entire furnace and get it checked out by an expert. Most likely, something has broken or become disconnected.
  • Clicking is common when turning your unit on and off. But, if you hear it from the control panel or outside compressor, you may have to reset the system.
  • Similar to an out-of-balance washing machine, the motor of your HVAC unit can become out-of-balance. When this happens, you will hear a vibration sound.
  • If you hear a hiss, it may be from improperly sealed ductwork. If so, the coolant is leaking, and you will want to get immediate professional HVAC assistance.
  • If the hissing comes from the compressor motors when you shut down the heat pump, the internal refrigerant valve may be leaking.
  • A screeching or squealing might indicate that the belt and/or motor bearings are having problems. This can be solved by adding the correct lubricating oil or getting an inexpensive repair from an HVAC professional.
  • A buzzing can come from either loose parts or a sign the motor is going out. Either way, you should schedule a diagnostic with a technician.

Normal Sounds

  • As stated earlier, you may hear a clicking sound when turning your unit on and off.
  • You might hear a quiet, continual hum from your HVAC system. This will come from properly working equipment when it’s in operation. Note that an outdoor unit will make more noise than an indoor one.
  • You may hear a swooshing sound as air rushes through the vents in your home.
  • A popping sound when turning your system on and off can simply be from the ductwork expanding.
  • If you hear a squeal or thump when the system turns on or off, its no cause for alarm. This is simply an indicator that your system is due for a tune-up.

Other Causes

  • If your HVAC unit uses isolation padding to absorb the noise, the pad may be worn down. These pads can begin to break and crumble after a while, which will lead to an increased noise level.
  • The refrigerant lines may have been installed too tightly. This is a simple fix that your HVAC technician can adjust.
  • The compressor is at the end of its lifespan or is malfunctioning.
  • There may be a piece of hardware in the motor system that has come loose, or the motor may be failing. In this case, you will want to get a professional technician to come out before any further damage occurs.

In Short

There are many different noises your HVAC system can make, but no matter the problems, your HVAC technician can solve them. If there’s a sound that goes away, its likely a minor issue that you can mention to your HVAC technician during the next maintenance visit. If the noise doesn’t go away or gets worse, then it’s time to call the experts.

We hoped this blog has helped you identify the cause of your loud HVAC system. If you’re still unsure what the noise indicates or have any questions, please call (877) 452-8527 or contact us on our website. We’re more than happy to help!