A strange smell from your vents can be more than annoying—it could signal a serious issue with your HVAC system. Here are five common odors Pasadena homeowners should recognize, and what they mean for your Pasadena HVAC setup.
1. Burning Smell
What it means:
If it’s dusty, it may be harmless—just the furnace burning off buildup after sitting unused. If it smells like burnt plastic or chemicals, shut the system off. You could have an electrical issue or overheating motor.
What to do:
If the smell doesn’t go away quickly, call a professional. Don’t risk a fire or component damage.
2. Musty or Mildew Smell
What it means:
Likely caused by mold or mildew on the evaporator coil or in ductwork. This often results from a clogged drain line or high humidity.
What to do:
Change your filter and schedule an HVAC inspection. Mold growth can spread quickly and affect air quality.
3. Rotten Egg or Sulfur Smell
What it means:
This usually indicates a natural gas leak—a potentially life-threatening emergency.
What to do:
Evacuate your home and call the gas company immediately. Do not turn on lights or electronics.
4. Chemical or Acetone Smell
What it means:
A sweet, sharp chemical odor could signal a refrigerant leak. These leaks reduce efficiency and can damage your AC.
What to do:
Turn off the system and contact an HVAC technician. A licensed professional must handle refrigerant leaks.
5. Decomposition Smell (Dead Animal)
What it means:
A foul smell may be due to a rodent or small animal that died in the ducts or near the HVAC system.
What to do:
Call a technician to locate and remove the source. You may also need duct cleaning and deodorizing.
FAQs: HVAC Odors in Pasadena Homes
How long should a burning smell last after turning on the heat?
If it’s just dust burning off, the smell should disappear within 30–60 minutes. If it lingers longer, turn the system off and call a professional.
Is a musty smell from the AC dangerous?
It can be. Musty smells often mean mold or bacteria are present, which can affect indoor air quality. It’s best to have it cleaned and inspected.
What should I do if I think I smell gas?
Leave the house immediately and call your gas provider. Do not use electronics, light switches, or anything that could cause a spark.
Can refrigerant leaks make you sick?
Most modern refrigerants aren’t highly toxic, but concentrated exposure can cause dizziness or headaches. Leaks also harm your system’s performance.
Will a dead animal smell go away on its own?
Eventually, yes—but it could take weeks, and the odor may linger in your ductwork. It’s best to have the animal removed and the area sanitized.
Pasadena HVAC Smells? Let’s Fix It
Strange smells are your system’s way of alerting you to a problem. Some are harmless, but others require immediate attention.
Contact Pioneers Heating & Air if your HVAC system smells off. We’ll identify the issue, make necessary repairs, and keep your Pasadena home safe and comfortable.
