December 01, 2016

How To Fix A Noisy Air Conditioner

How To Fix A Noisy Air Conditioner For Dallas Homeowners

When you have a loud air conditioner, the nature of the problem can depend on the type of you noise you hear. While a buzzing sound or the noise of air flow tend to be pretty standard, other sounds can indicate a more significant problem, some more so than others.

Why is My Air Conditioner So Loud? How to Fix a Noisy AC.

Problem: Noisy air conditioner
The outside condenser of a central air conditioning unit can be very loud. Read on to find the best solution based on the cause of the problem.

Solution:
Fencing one or all sides of an air conditioner’s outside unit can deflect noise. But experiment first: Prop up plywood around the unit so you can judge how much good a fence will do. If you decide to build a fence, keep it at least 3 ft. from the unit to allow airflow. For the best sound reduction, overlap fence boards instead of leaving gaps between them. Aside from a fence, there are a few other approaches you should consider:

  • If your condenser is older, the best solution is a new unit. Newer designs are dramatically quieter than those produced just a few years ago. And they save money. A high-efficiency unit might cut your cooling bills in half and pay for itself in three or four years. The downside, of course, is the initial cost.
  • If you already have a newer condenser, the worst noise is probably coming from the compressor. (Fans on newer units are very quiet.) Contact the manufacturer to find a sound blanket for your model or buy a universal blanket (search online for “compressor sound blanket”). Installation is easy. Don’t bother putting a blanket on an old unit—you’ll still hear the noisy fan.

Step 1 – Is the Fan Motor Squeaking

Is the sound coming from your fan motor? Split units have an inside and outside portion, either of which works under the same principle – they both have a fan with a motor. To examine your noisy air conditioner, remove the outside casing to reveal the inner part of your AC unit – you will notice the fan located just in front of the coils. If this is your problem, remove any debris from the unit and check the fan blades for dents or dings. A common problem when you are dealing with a squeaky fan blade is the dirt that accumulates on the fan blades, causing an imbalanced, noisy fan. For information on how to prevent this, see:

Even the slightest bend or imbalance in an AC blade can cause your blade to scrape its casing, also known as a fan cage. This will make for a very noisy air conditioner. If your blade is damaged, it will need to be replaced. Also, spin the fan with your hand to ensure that it is moving smoothly. If it is loose, tighten the center bolt with a wrench or an Allen wrench. If the sound you hear is squeaky, and you’ve tried everything else mentioned so far, then the bearings likely need some lubrication. If you want, 444 HVAC lubricant is available at your local hardware store but is unnecessary. The good old WD-40 lubricant will do just fine. If the bearings are still making a loud sound or if the blade does not rotate smoothly, call your local HVAC technician and they can replace your bearings for you.

If you hear a grinding sound, call your HVAC technician as this is a sign of pending bearing failure.

Step 2 – Noisy Air Conditioner – Rattling from Exterior Condensing Unit or Package Unit

The most common cause of rattling is something loose. If you have isolated the noisy air conditioner to your HVAC unit itself, again start by turning the unit off with the CB and with the thermostat, then check all exterior and internal panels. If loose, tighten them, but check the inside panels before the outside panels. It is a rule of thumb to work with him inside out when tightening your AC panels.

Step 3 – Why is My Air Conditioner so Loud? Examining Rattling AC Ducts

Again, if you are not experienced with this, ensure to only walk on support joists (the wooden pieces between insulation). See the pic on the left. Again, unless you are experienced, I’d recommend calling your local HVAC contractor.

Check all of your ducts for loose joints and tighten them with duct screws and HVAC tape as necessary. How? Just use common sense and seal leaks. Try not to over think it. If the rattling continues, you may have to call your HVAC contractor as the ducting currently installed may not be the proper size.

Step 4 – Then, ask what kind of sound is my AC making?

Again, before you can answer the question “why is my air conditioner so loud,” always start by figuring out where the sound is coming from – you can’t diagnose a problem if you don’t know where the problem is, to begin with! Once you have localized the problem, another way of diagnosing it is to listen to the sound it is making. Again, this is easier for an experienced HVAC technician, but here are a few general guidelines:

Listen to your ears – seems simple enough but the harsher a sound is, the more likely it is to be serious. If it hurts your ears, it’s time to turn it off and call a pro.

  • Mild Squeaking from Air Conditioner – Likely not serious – a bearing in need of lubricant or a dirty fan blade that is out of balance.
  • Rattling from AC or Duct – Again, not very serious – likely a loose panel in need of tightening, or a loose AC duct.
  • Grinding Noise – More serious – a bearing is likely going to fail, and if not replaced soon, it could damage other parts of your HVAC unit.
  • Hissing Sounds – Usually the most serious – if it is coming from your air conditioning unit, the most likely cause is leaking Freon. Also see, What is Freon? Don’t freak out though unless you are certain that it is coming from your air conditioner itself – hissing could also be loose ductwork, which is not that serious. When in doubt, give us a call.

Air Conditioning Fixing Tips

It is probable that you might be able to fix some problems with your air conditioning on your own. However, you will have to hire an air conditioning repair expert at some point in time. An air conditioning unit is quite a complex machine and when it breaks down and has to be opened its best not to try and repair it on your own. Call us for your home service and repair needs.

Suggested Reading

Ready for Service?

We're There When You Need Us!

877-746-6855