Why Does My Heater Smell Bad?

Recently turned your heating on for the first time this season, just to be met with a strange smell coming from the vents? In some cases, this can just be the dust that’s collected in the ductwork over the past few months getting stirred up. In other cases though, smells from your HVAC system can indicate larger problems. We’ll cover 4 of the most common HVAC smells, and when you should call for a professional inspection.


Musty Smell Coming from Air Vents

This is common if you live in a humid area, or you keep your home humid. It’s more common to smell this when you’re running your air conditioner due to the condensation buildup. However, it is still possible to smell a moldy or mildewy smell when running the heater. This happens when moisture builds up in the ductwork and causes an overgrowth of mildew and mold. When you turn on the air and it begins circulating, it can carry the moldy smell up through the vents and into your home. Beyond just smelling bad, mold in the air can cause serious health problems for you and your family.

If you’re experiencing a moldy smell from your HVAC system, you should call a technician to come service and clean your ductwork. They’ll also figure out why excess condensation is building up, and take steps to prevent it from happening again.


Burnt Plastic or Rubber Smell Coming from the Heater

This is a different smell than just smoke. The smell of overheating plastic or rubber is very distinct and is usually easy to recognize. If you’re noticing an overheated smell coming from your heater, there is likely an issue with the components inside. It can also mean there is an underlying electrical issue causing the system to overheat.

The smell of hot metal, melting or burning rubber, burnt plastic, or even an ozone-type of electrical smell can all be indicators that there is something wrong with your furnace. These smells can indicate a there is a serious fire risk. You should contact an HVAC technician as soon as possible.


Burnt or Scorched Smell from the Heater or Ducts

If you’ve ever smelled burning dust, then you’ll recognize this smell straight away. This is a common problem, especially if you haven’t changed your filters in a while. As the build up of dust in your system heats up, it begins to burn off. In turn, it gives off a distinct scorched dirt smell. The good news is that this should usually fade away after a few hours. However, if you notice this smell persisting after 24 hours, then it’s time to call in the pros. In the meantime, turn off the furnace using the shut off valve or close the gas supply.


Heater Smells like Rotten Eggs

If you have natural gas and are smelling rotten eggs coming from your vents or your heater, this is an emergency situation. There is very likely a gas leak in your home. Natural gas is odorless so a harmless additive called mercaptan is added to give it a powerful odor. This is to prevent gas leaks from going undetected. If you’re smelling it near your stovetop or another appliance, check to make sure that the valves are closed. If this is the cause of the smell, it should dissipate quickly.

However, if the smell is coming from your HVAC system, you should remove yourself and your family from the premises and call emergency services and your gas company. In the meantime, it’s important not to use any electrical equipment, appliances, strike any matches, or any similar activities that could cause a spark. Once the natural gas company has located and repaired the leak, you can call in an HVAC team for maintenance checks. It’s important to address any issues with your furnace that may contribute to leaks in the future!

Learn more about what to do in the event of a natural gas leak.


You Can Always Call Texas Ace HVAC!

If you find yourself dealing with any of these strange smells, it’s always a good idea to get a professional evaluation. Texas Ace HVAC is here to help with everything from regular maintenance and repairs, to filter replacements and more. We’re offer 24/7/365 emergency HVAC services any time you need them!

Give us a call at 817-240-6701 or contact us online.