Why Your New Heat Pump Smells
Why Your New Heat Pump Smells – 5 Common Causes & What to Do About Them
Introduction
You just had a brand-new heat pump installed, and now your home smells… strange. From burning odors to musty or chemical scents, it’s natural to worry. The good news? Some smells are harmless and temporary. Others may signal an issue that needs attention—especially in Florida’s hot, humid climate, where mold can take hold quickly.
At Millian Aire, we’ve helped Tampa homeowners troubleshoot thousands of HVAC systems over the last 30 years. Here’s a breakdown of why new heat pumps smell, what’s normal, and when it’s time to call for professional service.
Harmless Odors You Might Notice
Dust Burning Off
During installation and storage, a thin layer of dust can settle on coils or heating elements. When the system fires up for the first time, that dust burns away, producing a mild “burning” smell. This usually disappears within the first day of operation.
Protective Coatings & Manufacturing Residues
Heat pump parts sometimes ship with protective oils or coatings. When exposed to heat, these can give off a light plastic or chemical smell. It’s temporary and typically fades within the first week.
Odors That Require Attention
Smell Likely Cause Action Musty / “dirty sock” odor Mold or bacteria growth on coils or drip pans (accelerated by Florida humidity) Call Millian Aire for coil cleaning and drainage inspection. Burning or electrical smell Clogged filter, overheating motor, or electrical fault Turn off unit, check filter, and call if odor persists. Chemical / refrigerant-like odor Possible refrigerant leak or compressor issue. Shut down system and schedule immediate service. Rotten eggs / sulfur Often means pests or rodents entered ductwork or the unit Have Millian Aire inspect and sanitize the system.
Tampa Tip: Why Smells Linger Here
Florida’s subtropical climate makes our HVAC systems more prone to moisture buildup and mold growth than in most regions. Even a brand-new heat pump can start growing mold within days if drainage isn’t correct. That’s why preventive maintenance is critical in Pasco, Pinellas, and Hillsborough counties.
What Homeowners Should Do
- Run the System – If it’s just dust or coatings, odors will fade after a few heating cycles.
- Swap Your Filter – A dirty filter traps moisture and worsens smells.
- Check the Drain Line – Look for standing water or algae in the condensate line.
- Document When Smells Happen – Note whether it’s only at startup, during heating, or all the time.
- Call a Professional – If odors linger longer than 48 hours, or if you smell chemicals, sulfur, or burning plastic, it’s time for service.
When to Call Millian Aire
At Millian Aire, we specialize in keeping Tampa homes odor-free and comfortable year-round. Whether it’s a harmless startup smell or an early warning of mold or refrigerant issues, our licensed technicians can quickly diagnose the problem.
- Schedule a Heat Pump Inspection
- Explore Our Maintenance Plans
- Check Service Availability in Your Area
Conclusion
Noticing smells after a new heat pump installation is common—but it should never be ignored. While some odors are normal, others point to issues that can worsen over time. If you’re unsure, don’t take chances. Call the trusted experts at Millian Aire AC & Heating to keep your system safe, clean, and efficient.