368. Switching Back Odor
28 Jan 2026 · 5 min
Derek Cole explains why your heating smells musty when you switch from AC. Condensate builds up on coils and in drain lines over summer, and microbial growth can develop. The smell usually clears after a cycle or two, but if it persists, you need professional maintenance or UV treatment.
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Foreign.
I'm Derek Cole, host of the Derek Cole Podcast and we believe in taking the time to explain how things work for your air at home or your business. And we also believe you deserve clean air in that home. And that is why we founded the Healthy Home Challenge. It's a five day online video series with daily emails, worksheets and even quick action steps you can take to protect you, your family and your co workers. If you haven't joined us yet, you can sign up. It's free to free five day access. You can go to Simmons One Hour Comm. You'll see a link to learn more about indoor air. You've probably known for a while that you need better indoor air at home or at work. After all, we spend 90% of our time indoors these days. Your breakthrough awaits at Simmons One Hour Comm. Now let's get into today's episode. Please listen closely and maybe even take some notes so you can remember these insights of home comfort and energy savings. And share this episode with three of your friends because we all need to share better ways to be more comfortable at home. Be sure to tag me or DM me on Instagram Derek Mcole so I can say hi. Thanks again for listening and let's begin.
Foreign. Welcome back to Winter Weather. It's around here anyway, it's been a couple days into the weekend of, you know, being warm, really warm weather for December. And you could be like me. I mean, a few nights we had to turn our AC on, get it down to 68 degrees, which is, which is where we like it at bedtime. So we had to turn the AC on. But now we're back to heating. We're back in the heating mode. Our thermostat is set. I keep my own auto, but the, the heat is the one that comes on and not the AC because of the temperatures. But just know that the first time you have the heat come on after you've used the ac, you're going to have that kind of a musty odor, musty smell coming out of the vents. And that's really because AC is about dehumidifying. And a product of dehumidifying is what? Water, moisture. So that water obviously gets on the coal and the drain pan and the drain line. So when you switch back over to heating mode, you are not dehumidifying, you're in heating mode. So the first time you switch it back over, you're gonna have that musty kind of odor coming out of the system, but it's something that's gonna last one maybe, maybe the first one or two times you turn back to eating, it really shouldn't last much longer than that. Really after the first time it shouldn't come back. But if you continuously have that musty odor smell with the heat, then you need to get a professional out there and see what's going on. It could be something as simple as maintenance because you could be having a drainage problem where water is sitting in the drain pan instead of going out the drain line or something might be on that coal as far as a fungus or some kind of bacteria causing the odor. And you might need a maintenance or a UV on that system to start controlling that situation. But just know that if you use your AC and you're switching back to heating that you're going to have that smell. If you have it more than a few times when you start, then you have a another problem, a different set of problems that needs to be addressed and needs to be looked at. But welcome back. Welcome back to the winter weather. Frankly, I'm glad to see it back.
Okay, I hope you enjoyed this episode of the Derek Cole Podcast. Tell some people about this episode. It's on each of us really to spread the better ways to be healthier and more comfortable in our homes and workspaces. I'm asking you to be the dealer of positive and life changing messages in your circle of influence. Take a screenshot right now and share the screenshot and the link to this episode with three of your friends today. Share on Social Media Use the hashtag Healthy home. That's hashtag Healthy home. We are always giving away shout outs prizes to our community. If you would like to help me personally then please rate and review on Apple Podcast Give us some stars. Leave a review because that stuff actually does help and I read all the comments. So my last thought for today, please remember you deserve better air at home and greater comfort at home. Don't settle for being uncomfortable for heating air every single month. We are so thankful for having you here in our community and be sure to go deeper with us at simmons1hour.com.
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