Why is My Air Conditioner Making a Rattling Noise?
If your AC is making a rattling noise, it can be unsettling or disruptive.
But don’t worry, there are a few common explanations for why your AC unit is making a rattling noise, like:
- Debris in the outdoor unit
- A displaced fan blade
- A damaged motor
- Loose unit panels
Below, we’ll discuss each of these issues and their solutions.
Think your AC issue may be something else? Contact us! Our team is experienced in all AC repairs and can easily diagnose and repair your AC at a time that’s convenient for you. Learn more about our AC repairs or…
Issue #1: Debris
Because your AC unit is outside, it’s fairly easy for debris like sticks, leaves, rocks, etc. to get caught in your unit and make a rattling noise as your AC runs.
Although the rattling noise in itself is not a huge problem, debris can severely damage the parts of your AC system.
The fix: Contact a professional to come and clean your outdoor AC unit. If there is debris lodged in your unit, you should hire a technician to carefully clean out the unit, to ensure no parts are damaged in the process and to prevent further damage.
Going forward, you can help prevent debris from entering your outdoor AC unit by clearing away all shrubs and trees within a 3-foot radius of your unit.
Issue #2: Displaced fan blade
Your outdoor AC unit has a fan inside. If one of the fan blades is misaligned or loose, it can hit the casing, causing a rattling noise.
A displaced or damaged fan blade could be the result of:
- Normal wear and tear
- Debris entering the outdoor unit and knocking a fan blade out of place
- Improper installation
The fix: Hire a professional. An experienced tech will need to come to your home, evaluate your outdoor AC unit and repair or replace any damaged parts.
Issue #3: Damaged motor
There are several parts of your outdoor AC unit that are powered by motors. If one of those motors starts to break down (debris or old age), it can cause the internal parts of the motor to become loose, which is why you may hear a rattling noise coming from your AC unit.
The fix: Contact a pro. If you do have a damaged motor, a technician with experience will need to come and repair or replace that part of your system.
Note: This isn’t a repair you want to wait on, as a damaged motor could be causing long-term damage to your system and spike your energy bills.
Issue #4: Loose panels
Did you recently repair your AC unit (or have your AC repaired by someone else)? If so, this could be your issue. If the panels on your AC unit aren’t tightened properly, they can rattle when your AC system is turned on.
The fix: Check the panels on your outdoor AC unit and tighten any loose screws.
If your AC is still making rattling noises, it’s probably time to contact a professional. There could be a different or larger issue that’s causing your AC to rattle.
Other reasons your AC may be rattling
Don’t think any of the above apply to your AC system?
There could be a few other reasons your AC is rattling, like:
- A dirty filter- This can cause your motor to work too hard, causing a rattling sound.
- Undersized ductwork- This can also cause your AC motor to overwork, resulting in a rattling noise.
- ISO pads not installed- Without pads, normal vibrations from your AC system can transfer to your home.
- Air handler or furnace not installed properly- This can cause the hangers to vibrate on roof trusses, making a rattling noise.
- Old register- The hinges of old registers loosen up and start to rattle over time.
- Out of balance indoor blower motor and/or wheel- If either of these parts is out of balance, it can cause a rattling noise.
Is it time to repair your AC system? Hire the best in Phoenix: George Brazil
If your AC does need to be repaired by a professional, you want to hire the very best. At George Brazil, our techs are fully trained to handle any repair… the right way.
The best part? We always keep our trucks fully stocked, so if you do need a repair, we can be there as quickly as possible (depending on the repair, we may even be able to fix it that same day). Learn more about the AC services that we offer or...
Justin Stevens is a 17-year veteran of the trades and one of the masterminds behind George Brazil’s world-class training lab for technical expertise and sales training. Justin has held several titles during his tenure at George Brazil ranging from Lead Installer and Installation Manager to QA Manager and Field Operations Manager. Today, Justin is the Director of Field Operations and plays a pivotal role overseeing all of George Brazil’s field departments.