#AskDerekCole Episode 97
28 Jan 2026 · 4 min
Derek Cole answers questions about a furnace triggering smoke detectors and a strong gas smell. A new furnace's heat-exchanger coating produces a temporary burn-off odor. He stresses checking gas pressure with a contractor and explains when to worry about carbon monoxide.
Chapters
Hey, on this episode we talk about my smoke detector going off in the heating cycle and why do I have a gas smell? You ask your comfort and energy questions and they get answered. This is the Ask Derrick Cole Show. Hey, this is Derrick Cole. Welcome to episode 97 of the Ask Derrick Cole Show. Answering your home and energy questions in such a beautiful week. I'm wearing a short sleeve zip. The day, it's going to be nice. It's like hot in the day, cold at night. It's that weird time of year where you got heat and air maybe at the same time. But anyway, that's just my house.
Maybe, maybe I turned my furnace on and my smoke detector went off inside my house.
That's probably not a good thing to happen. Your smoke detector should be going off in the house. Now, if you have a newer furnace, as in it was put in this summer, probably what happened is it was too hot to actually when you get a brand new furnace from the factory, it has a coating inside the heat exchanger. And usually we or contractors test that gas pressure and test that heat exchanger if it's not too hot. But if the house is already 95 degrees because it's 100 degrees outside, it's kind of hard to fire up the gas furnace. So usually that burns off at that point. Now, if it's never been turned on before and it's being turned on now, you would get that to happen. But also what needs to happen is you need to get up to that contractor to come back to check your gas pressure. Because if it was never fired, you want to make sure you're burning the right kind of flame in that heat exchanger. Also, it can happen multiple times. So if it's a, again, a new furnace, it was tested at the beginning, it was pressurized, it was checked out maybe the next two or three times you light it at the beginning of the season, you might get that kind of a smoky thing happening. And that's completely normal. But you should always have a maintenance to make sure. Depending if it's new or old, you still make sure the gas pressure going to it is good. It's kind of like, it's kind of like tire pressure. Okay. Just because your tire pressure was good last winter doesn't mean it's going to be good this winter. You should always check it. That's why they check it when they change your oil and they do all the checks in your car. Your gas pressure is one of those things because the LP company or the natural gas company, something might have Changed and you might have different things going on and you might need adjusting. So that needs to be taken care of. Now if you have an older furnace, that should not be happening at all with this smoke, you have a whole nother problem. But usually that call comes in on newer furnaces because of that coating in that heat exchanger. Makes sense. It's kind of a, it's kind of a. What do you call it? Grease is kind of, it's kind of a substance like that, that it's just, it is what it is. It's brand new. It's a new car smell, new furnace smell. I don't know, I don't, I don't know specifically what they use, but they use something.
Why am I getting a strong gas smell when my heat is warm working?
You should not be having a gas mill in your house or outside of your house. What happens in our business, from the regulator to the house is usually our responsibility. Anything the other direction is the gas company, it's the OP company or natural gas and that's their deal. They don't want us touching anything beyond that and that's fine. So if you go outside and have that smell, you should turn the gas off. You have a gas shut off, right? A gas shut off. Use it, turn it off. Obviously don't light cigarettes or don't use a lighter to see what's going on. That's not a good idea with a gas smell that's going to cause a problem. Now inside the house again, you could be, could be a gas pressure problem, could be a gas valve problem. You need to have. It goes back to what I just said. You need to have a maintenance done to make sure you're being operated properly. Because gas obviously is nothing to play with. And if you have any gas appliance in your house, whether it be a furnace or a water heater or a dryer or a stove, you should always have a carbon monoxide detector because that you cannot smell, that you cannot smell, you cannot see. But it is a byproduct of gas. So if you have gas in the house that needs to be installed as well. And we install with every new furnace and you should have one. But the gas smell, natural gas and lp, you know, they put that in there so you have that smell so you can identify, hey, I smoke gas. We need to get it checked out. It's not a normal thing to have a gas smell. So I would check that out. Just don't let it roll, alright? It's episode 97 of the Ask Derrick Cole show. Be sure to hashtag your questions. Ask DerrickCole. Or when you see me, just say, hey, I have a.
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