In this episode of the Ask Derek Cole Show, Derek answers three common HVAC‑related homeowner concerns. First, he explains how to set ceiling fans for cooling versus heating, emphasizing that fans move air for occupants, not rooms, and that the direction switch should be adjusted seasonally. Second, he addresses a persistent bleach‑like odor in two back bedrooms, noting that the source is unlikely to be the whole‑house AC and is often traced to the basement or stored cleaning chemicals; he advises checking the basement, running the AC to dehumidify, and ensuring proper ventilation when using cleaners. Third, he clarifies why a burning smell can appear the first time a heat pump’s backup electric strip fires up after a season of inactivity—dust burning off is normal—while a raw gas smell is a serious safety issue that requires immediate professional inspection and a functional CO detector. Throughout, Derek offers practical diagnostic steps, safety reminders, and encourages listeners to submit questions via #AskDerekCole.
Questions this video answers
Yes. Set the fan to push air upward in cooling mode and downward in heating mode; fans cool people, not rooms, so run them only when occupied.
The smell is unlikely from the AC. Check the basement for sources, ensure cleaning supplies are stored properly, run the AC to dehumidify, and ventilate any cleaning chemicals.
When a heat pump’s backup electric strip hasn’t been used for a season, dust accumulates and burns off the first time it runs, producing a temporary burning smell.
A raw gas smell is dangerous. Contact your gas company or HVAC professional immediately, check gas pressure, and ensure a CO detector is installed.
Chapters
Hey, on this episode we talk about a bleach smell in your unit, which direction are my fans supposed to be going, and should I have a burning smell when my heat comes on? You ask your comfort and energy questions and they get answered. This is the Ask Derrick Cole Show.
Does changing the direction of my ceiling fan help anything?
It does. You're supposed to have it one way on air conditioning or when it's hot outside and downflow on heating. The reason is because heat rises. So in the fall and the winter when it's cold, you want obviously the warm air to come back down to living space. So that's why you have a reverse function on that fan because then it pushes that hot air back down. Just to rise back up again. So opposite way in the cooling season, uh, you want the hot air out of the house, so it's blowing it up, taking the hot air going up, bringing the hot air going down. So yes, it does make a difference. You do need to pay attention. It's a little switch, right? Which way is it going? Which way is it going? So yeah, it does make a difference. Um, but just remember, fans cool people, not rooms. So if you're not in the room, there's no reason to have the fan on. The fan gives you a wind chill effect, or in this case, in the wintertime, I don't know, like a desert effect. I don't know. I'm not sure. But I'm saying that, say this, don't leave the fan on when you're not in the room because it's doing nothing for the room or for anything but having the fan on. Yes, it does make a difference.
I keep smelling a bleach smell in two back bedrooms of our home. We have a whole house AC. Could this be the source of the smell? The home does have a basement.
Um, I don't know. That's one of them deals that I would have to check out, or somebody needs to check out to see where the smell is coming from. Now You said basement, so something could be in the basement that you have that's causing that smell. Because I— don't hold me to this, but I believe studies have shown that over 60% of the indoor air comes from under the house. So it's obviously migrating up from the basement. So that could be one of the problems. So I would check that out first, see what's in the basement. If there's rooms to make sure something isn't coming up into the space that you're smelling. But yeah, that is kind of weird, so probably want to check that out. But it's not caused by your AC. I mean, it's not blowing any kind of Clorox smell into the environment. If the unit was just cleaned or just maintenance, maybe you'll get that smell, but I mean, that should go away in a few days or a few cycles, uh, depending on, on the weather. Now with this weather we've had recently, uh, your fan— your house is probably getting a little musty kind of smelling because it hadn't run a whole lot. So, um, what I did when I got back home was turn the AC back on, dehumidify, get rid of some of the smell, and that works. So just remember that when it's kind of in between like it is this time of year And this season we're going to where it's cold in the morning or cooler in the morning and warmer in the afternoon and then cooler again. Your unit's not going to be running a whole lot. So watch that temperature to make sure you're circulating the air. Otherwise you get that damp, stale kind of environment. It's just because it's not running. It's not pulling the air in and dehumidifying it. Clorox. Not really sure what's going on there. I would, since you said basement, I would check basement to see what's in that environment. If you have any kind of cleaning supplies, make sure everything's where it should be. If you read the instructions on cleaning supplies, they do want you to crack a window whenever you use them. A lot of people don't know that. That's why the products we put in the home is all natural products. It's not like a bleach or anything like that, that people who are sensitive to it can be affected by it. So check all that, and if you still have a smell, get it checked.
This one we've actually had like 3 calls on, and I've personally answered the phone for besides Carolina asking.
Hey, this next question we have had 3 phone calls about it in just like yesterday. Oh, like in one day.
Why is it that you smell something burning when you turn your heat on for the first time but not after that?
So what that is, is I'm assuming these folks have heat pumps. What happens is with your heat and your strip heat coming on as backup heat over the long summer, They're not used, they gather dust. So on that first time it's used, it's really burning the dust off. If you have a maintenance done, if it's done in the springtime, middle summer, you'll get that more often. As we're doing maintenance now where it's cooler, of course we're activating that heat strip to make sure it is working. But again, if you had that maintenance in the summertime, it's probably going to have that smell this time of year. So it's just the dust and stuff burning off. There's nothing to be alarmed about. It does kind of smell like an electrical burning smell, and that's the dust, so it's nothing to be alarmed about.
Maybe you should address too, because I had this phone call the other day, the difference between like that kind of smell and this lady called in and said, "I just turned my heat on for the first time, but now it smells like gas." Yeah, you shouldn't be having a raw oil gas smell.
Yeah. So with that, you could have a gas pressure issue or a gas line issue. A lot of the units we go to, we do have to adjust the pressure every year. And depending on if it's LP, if they refilled the tank, if there's somewhere in a gas line during the summer, maybe a rock hit something and did a little thing. Yeah, you shouldn't be having a kind of a raw gas smell when it comes on. I would call the gas company or your heating and air company to check it out because that's two different kind of smells. I mean, one's a dust kind of electrical burning smell on a heat pump and one's just raw gas and that's very dangerous. So you don't want to do that. And again, I'll say it because it's very important with any gas appliance, you should have a CO detector in your home. You want to make sure because LP or gas in general, they put that smell in there. I mean, it's not natural rotten egg smell. They put it in there for a reason so you can smell it, detect it. But with CO, when it leaks out or if you got a hole in the heat exchanger or or whatever, you know, that's— you're not going to see it or smell it. So that's why you need a detector to make sure you're safe and your family is safe, because it's something that you can't smell. So yeah, and I think our CO detectors also detect natural gas when they come in. So again, you shouldn't be having— you shouldn't have a raw gas smell. So Bad smell, electrical burning, heat strips for the first time of year, that's okay, that's gonna happen. Raw gas, not okay, you need to call somebody. That's it, that's episode 50. We're in the 50s now. That means the next one's 51 and then 50. Okay, so if you have any questions, hashtag them #AskDerekCole, we'll get them on the show. I appreciate the sharing and everything on Instagram and Facebook, and keep the questions coming. We'd love to have him on the show.
