How HVAC Can Help With Odors: 6 Ways to Make Your Home Smell Fresh

Last Updated on May 14, 2025 by Chad Peterson

Learn how HVAC can help with odors in your home. Your HVAC system can help eliminate odors by using simple upgrades to keep your home smelling fresh year-round.

🌬️ 1. How HVAC Can Help With Odors in Your Home

Before you spend money on filters or gadgets, inspect your ductwork. I inspect my customers’ duct systems and filter setups on every service call.

I remove the furnace doors and inspect the blower and A/C coil (if there is one). If the system has a poor filter setup, the blower and coil become targets for dust, pet hair, and even mold — all of which can build up and spread odors throughout the house. I’ve written a full article on how to clean an A/C coil and drain pan — you can read it here.

You can remove the vent covers and look inside the ductwork with a flashlight and a small mirror — if you see buildup or smell something foul, that could be your problem. If you’re uncomfortable doing it yourself or want peace of mind, hire a professional for a thorough duct inspection and cleaning. (Just another article written by Chad Peterson)

Some ductwork has insulation lining the inside of the duct. That insulation attracts dust and unthinkable stuff like a magnet. It’s hard to clean even with a good duct cleaning system. Sometimes it even comes loose and blocks air flow.

🧼 2. Upgrade to Activated Carbon Air Filters

Standard HVAC filters trap dust, but they don’t do anything for odors. Activated carbon filters are designed to absorb odors like pet dander, cooking fumes, and smoke. This is something that is best done by someone who understands airflow and static pressure. This article talks all about which filter is best for your system and some things to consider about static pressure.

The short answer, if you don’t want to read my excellent article, is that adding filters can create an unknown restriction, causing overheating in the heat cycle and freezing coils when in the cooling mode.

This is just my opinion. You may be handier than I give you credit for, but I just like people to take precautions. Bottom line is that activated carbon air filters will help eliminate odors.

🔆 3. Add a UV Light to Your HVAC System

UV lights are installed inside your HVAC system, usually near the evaporator coil or inside the air handler. Their job is to kill mold, bacteria, and other microorganisms that can grow on wet surfaces inside the system — especially the coil and drain pan.

These organisms are often the source of musty or “dirty sock” smells when the A/C runs. A UV light won’t mask odors — it removes one of the main causes.

UV lights run continuously when the system is on. They don’t clean the air directly as it passes by, but they help keep internal components cleaner, which improves both air quality and system efficiency.

Installation is typically done by a professional. The bulb needs to be replaced every 1 to 2 years depending on usage and manufacturer recommendations.

💨 4. Improve Ventilation with an ERV or HRV

If your home feels stuffy or odors tend to linger, you may need more fresh air. Whole-house ventilation systems like ERVs (Energy Recovery Ventilators) and HRVs (Heat Recovery Ventilators) bring in clean outdoor air while pushing out stale indoor air. These systems quietly improve airflow and reduce trapped odors — especially helpful in tightly sealed homes.

💧 5. Reduce Moisture with a Whole-House Dehumidifier

My wife and I spent a year in Illinois. I did HVAC for about 25 historic homes and over a hundred missionary homes. They needed dehumidifiers. It was a constant effort to keep the humidity low enough to keep the mold from growing.

Our home is in the high desert of Central Oregon. Here, we need to add humidity to fight off the dry skin. Equipment that dehumidifies the air won’t break the bank. These dehumidifiers come in portable units that can be set in a corner. It’s best to provide some way to drain the accumulated water outdoors.

Click the button to see the type of dehumidifier we used in Illinois, and you can view some of them here on Amazon.

Some dehumidifiers are made specifically for basements. Be sure to pick a size that matches your needs.

Moist air holds on to smells — especially in basements or bathrooms. A whole-house dehumidifier connected to your HVAC system keeps your indoor humidity in check and helps prevent musty odors. It also makes your home more comfortable overall.

🛠️ 6. Seal Up Leaky Ducts

There’s a lot to consider when start to seal up leaky ducts, but it can be one of the most effective ways to improve both air quality and energy efficiency in your home. I’ve sealed plenty of duct systems over the years, and I almost always noticed an immediate improvement in noise, airflow, and system performance.

If you can’t access all your ductwork — especially if some runs through a crawlspace or attic — focus on sealing the duct between the filter and the furnace. That’s the most important section to seal, because it ensures that all the air entering the system passes through the filter, not around it.

The good news? This is an easy DIY project for most homeowners. You can check local hardware stores, but the best products are not readily found there, in my experience. And no special tools are needed. Just a cheap 2″ brush and a razor knife will do the trick.

There are a few solid products that make duct sealing straightforward. I recommend and personally use two — one is a foil-backed tape, and the other is a brush-on paste sealant. Here are direct links to both on Amazon for price and availability:

Both of these products have specific uses. The FoilMastic tape is almost permanent when applied to a clean surface and pressed firmly — I use it around duct connections near HVAC equipment. It’s strong but still removable with effort if needed.

The Flex Grip 550 brush-on sealant is excellent for sealing seams, cracks, and even fairly large gaps in metal ductwork. You’ll be surprised at how much it can fill. On bigger cracks, I sometimes insert a bit of metal first, then brush over it with the sealant for a long-lasting fix.

And remember — leaky ducts don’t just waste energy. Ducts that run through attics, garages, or crawlspaces can pull in odors, dust, and moisture from those areas. Sealing the system keeps the air cleaner and helps your HVAC system work the way it should.