5 Creepy Things That May Be Lurking In Your HVAC System And What You Can Do About Them - Sun Heating & Cooling, Inc.

5 Creepy Things That May Be Lurking In Your HVAC System And What You Can Do About Them

HVAC issues

Spooky season is finally here, and while you probably won’t find any ghosts in the house, your furnace may be home to much scarier things.

From creepy crawlies to horrifying odors, there are a lot of things that could be living in your heating and cooling system. Luckily, most of these unwanted guests can be taken care of with a few simple steps.

So here are five things that could be lurking, and five ways you can get rid of them.


Cockroaches, spiders, termites, and even bed bugs can get into your furnace through a few vulnerable spots. Some of the places that give insects easy access to your unit (and home) include the ductwork and tiny openings in your unit. You may not be able to keep bugs out completely, but you can definitely decrease the number that can get in.

The first thing to note is that you shouldn’t spray insecticide into your furnace as it will contaminate your air. A better way to get rid of bugs is to seal up any spots that they can crawl into. And then investigate having mesh nets installed on your vents to keep them out.

Dust and cobwebs

A large amount of dust and cobwebs is common when you haven’t used your unit in a long time. But they can also build up if you haven’t changed your air filter recently.

The main purpose of an air filter is to catch dust and debris so that it doesn’t destroy your system. And it should be changed every three months to ensure it keeps doing its job. Vacuuming the air duct could also help solve this problem.

Internal A/C and furnace parts also tend to build up dust after a while, but they can be trickier to clean as you often don’t have direct access to those areas.


Mold is a fungus that thrives in moist and dark environments, so your heating and cooling system may be the perfect place for them to develop. Unfortunately, mold is sporadic, and running your unit with mold inside may cause it to spread and grow all over your home.

If you notice mold in your system, it’s better to have a professional remove it. Trying to do it yourself increases the chances that the mold will spread and become a more serious issue.

Bacteria and viruses

Your furnace recycles the air in your home. And once germs and bacteria get into your home, the unit won’t be able to get rid of them. They may set up shop in your system and get moved around the house continuously, causing you to get sick more often. 

The easiest way to combat this is to create proper ventilation by opening windows. But in extreme weather conditions, this may not be possible. For those cases, you may want to explore having a UV light, or another air quality solution, installed to kill germs and bacteria.  Contact the professionals at Sun for the best recommendations for your home!


There’s no shortage of nasty smells that can develop in your heating and cooling system. And each smell has its own unique meaning. For example, a musty, damp smell means there’s mold in your unit. If you smell chemicals, your A/C refrigerant is probably leaking. And if you smell rotten eggs (sulfur) from your furnace, then turn off your system and call a professional – there’s been a gas leak. 

Have questions about the spooky state of your furnace in your Oakland County home? Justcontact us onlineor call us: (248) 986-1506.

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