When you turn your AC on, you want to smell clean, dehumidified air. So it’s frustrating and confusing to smell burning rubber, plastic, or some other burning smell.
If this is happening to you, you likely want answers and you want them now.
7 Causes of Burning Plastic From Your HVAC Unit and What to do Next
Don’t worry, here are the seven most likely reasons your AC smells like its burning.
1. Your AC is Burning Off Dust
If you live in Florida or another hot climate, you probably don’t use the heat setting on your thermostat very often. Don’t worry if you just turned on your heat for the first time in a long time and you notice a burning smell.
The smell should go away in a few minutes.
After months of not being used, your HVAC system may collect dust. The dust will burn off when you turn your system on again, and this will cause a burning smell.
What to Do: Wait for the smell to pass. If the smell doesn’t pass after a few minutes, there may be another reason for the smell.
2. There’s a Fire
It’s possible there’s a fire in your home and the AC system is re-circulating the burning smell throughout the house.
What to Do: Look for signs of smoke and fire, evacuate your home immediately, and call 9-1-1.
3. Overheating Motor
Inside your system, there’s a fan that blows air throughout your home. This fan requires a motor to function.
Over time, the bearings on the motor can wear out and cause the motor to overheat. Thus creating a burning smell.
Solution: If you haven’t noticed the burning smell before, turn off your system and try lubricating the motor’s bearings. Or, if you’d rather, contact your local HVAC technician to fix the issue.
4. Bad Capacitor
The motor powers the fan. And the capacitor powers the motor. Just like the fan needs the motor to work, the motor needs the capacitor to work.
If the capacitor breaks, the motor can overheat and produce a burning smell.
Solution: To fix the issue, we recommend turning off your system. Then contact your local HVAC technician.
5. Broken Fan Belt
It’s possible your system may have a belt-driven fan. The fan belt is made of rubber and helps spin fan blades the circulate air throughout your home.
If the belt is broken, it may get overheated and produce an odor that smells like burning plastic or burning rubber.
Solution: We recommend turning off your system and contacting your local HVAC technician to replace the fan belt and properly fix the problem.
6. Clogged Air Filter
When an air filter gets dirty, it impedes the air that your system can take in. This puts unnecessary strain on your system, especially on the motors.
This can force the motor to work harder than it should, become overheated, and then produce a burning smell.
Solution: To prevent this from happening, clean your air filter regularly and replace every few months (one to two in the summer, especially in Florida).
7. Electrical Issues
Our houses these days require so much electrical circuitry. Your AC system is no different. The burning smell may be coming from an electrical issue.
Solution: Turn off your system and contact your local electrician to fix the problem.
Prevent Burning Plastic Smells With Regular HVAC Maintenance From Colman Heating & Air Conditioning
When you have your system set to cool, you want cool air to fill your home, not hot air. If you find your system blowing hot air when it’s not supposed to, we can help with a free estimate on maintenance, repair, or a new system.