In this Ask Derek Cole episode, host Derek answers listener questions about residential HVAC systems. He explains the fundamental difference between gas furnaces (natural gas or LP) and electric heat pumps, noting that heat pumps are fully electric while gas furnaces rely on combustion. He introduces dual‑fuel systems as a way to combine the efficiency of a heat pump in milder temperatures with the cost‑effectiveness of gas heating when outdoor temperatures drop below roughly 40‑45 °F. Derek then compares split‑system units to packaged units, highlighting that split systems receive better manufacturer warranties, are typically installed indoors and outdoors as separate components, and are preferred for durability, whereas packaged units are a single outdoor box, easier to install, and common in low‑rise homes or commercial settings. Finally, he discusses efficiency: modern gas furnaces achieve 95‑98 % AFUE, while electric heat (including heat‑pump backup resistance heating) is technically 100 % efficient but can become expensive in very cold weather due to high electricity draw. He recommends dual‑fuel setups where possible, prefers natural gas over LP, and tailors system choice to climate and existing utility infrastructure. The episode ends with a call‑to‑action for viewers to submit more questions and follow the channel on social media.
Questions this video answers
A gas furnace burns natural or LP gas, while a heat pump is fully electric. Dual‑fuel systems combine both, using the heat pump in milder weather and switching to gas when temperatures drop below about 40‑45 °F for better efficiency.
Split systems have separate indoor and outdoor components, usually come with better manufacturer warranties, and are preferred for durability. Packaged units house all components in a single outdoor box, are easier to install, and are common in low‑rise homes and commercial applications.
Modern gas furnaces achieve 95‑98 % efficiency (AFUE), while electric heat (including heat‑pump backup resistance heating) is technically 100 % efficient but can become costly in very cold weather. Dual‑fuel setups often provide the best overall efficiency by leveraging the strengths of each fuel type.
Chapters
You ask your comfort and energy questions and they get answered. This is the Ask Derrick Cole Show.
What is the difference between a heat furnace and a heat pump?
Gas furnace and heat pump. Now you do have some electric furnaces. I haven't seen those in many houses outside of mobile homes, and in mobile homes you have the electric furnace in the closet area and then you have an AC outside. That is not efficient. So what we do in that situation is we actually put a heat pump outside, keep the electric furnace inside as a backup heat source. So When you talk about furnace, you usually don't want gas. So the difference is gas versus electricity. So when you have a gas furnace, you have natural gas, LP gas operating that furnace. Heat pump is strictly electric. There is no gas involved in it unless you get a dual fuel system. Now we get the phone calls quite a bit of, hey, the gas is going really skyrocket. I want to change out my gas, I want to go straight electric. And the answer to that is dual fuel. You can do it in a package or split, and basically it is more efficient in this climate, or any climate really. Once you drop below 40 degrees, it's more efficient to heat with gas than electricity. And the reason being is that electricity, you have to use the backup heat source when it gets really cold outside. Using that backup heat source works, but it is quite expensive. So the best way to have it is heat pump until it gets to about 45, 48 degrees, switch over to gas. Using the best of both worlds, and you're getting the most out of each system. Because, you know, you get to 50, 60 degrees, if you want to turn the heat on, electricity is the way to go because it's very simple for it to to operate in those temperatures, whereas gas is not as efficient as electricity in that situation. So furnace, you're talking about gas, and heat pump, you're talking about electricity.
What is the difference between a split unit and a packaged unit?
Split and a package, well, what is the difference in— let me add to that, which one is better? Which one is better? Hey, look at there. Um, the manufacturer actually gives you a better warranty on a split system than a package system. So that is telling me as a consumer, hey, this is probably a better application and probably lasts longer if they're giving me a better warranty with it. So it kind of tells you a split over package. You see a lot of package units, especially in North Carolina, when you have low houses. A package unit is a big box outside. Everything is in that box outside, so it's all in one. These really are popular on commercial applications. We have rooftop package units, and they have taken that application and brought it to the ground. So these low houses, you have a lot of package units. Frankly, they're probably popular with— how would you say it? It's probably popular with jacklegs, people who don't have a license, because it is an easier product to install, easier product to work on because you don't have to go to any other place. It's all outside, it's all contained, it's all one system. Now saying that, when you get a split, You have an indoor section and an outdoor section. Go back to the first question about furnace or heat pump. You have that one piece under the house and in that it could be vertical in the closet or vertical in the mechanical room or a garage. And then you have the condenser outside. So split is a because it's split. It's two systems. You have a copper line going to the outside unit, and that outside unit is then feeding the inside unit. So package all together, split, split up, you have two different pieces.
What is more efficient, gas or electric heat?
Today they make 95, 98% efficient furnaces. I mean, it's crazy. So basically what that is saying is for every dollar you spend in heating, you're getting 95 cents of heat in the house. The other 5 cents is going up the flue. Now with combustion, you're always going to have some kind of loss. It's never going to be 100% efficient, whereas electricity is 100% efficient because there is no loss. It is efficient that way. The problem becomes when it gets cold outside, whereas you're using the strip heater or the backup emergency heat, and that's 100% electricity. And you go out to your panel where your power comes in, you see that little thing that's like spinning like crazy, and it's like, whoa, it's because you're using electric heat and you don't have that with gas. I mean, if you go to a house, especially older homes with all gas appliances, they have a gas furnace, they have a gas dryer, they have a gas stove, they have a 100-amp panel in the house. That's not a lot of electricity, whereas you go to a newer home with all electric like my house, you know, everything is electric—stove, heat pump, dryer, everything's electric—we have a 200-amp panel. We use more power, so it's kind of a give and a take. Use more power, but if that's the way you want to go, that's fine. Again, the most efficient way is really dual fuel. I mean, If I could— I'll just use me for example— if I could have natural gas at my house that ends, I think it's like 4 or 5 houses down the road, natural gas is right there. So if they brought that to me, I would take it. I would switch out my unit to a dual fuel, keep my heat pump, put it in the gas furnace, probably a 95% gas furnace, and use that natural gas heat because it is more efficient, and natural gas is probably the best source you got. I mean, if you have a choice between natural and LP, you want to pick natural. LP is a little more corrosive. It's just that in nature. It has a little more water into it because it's a man-made thing, whereas natural gas is natural, so it's not as corrosive. So Depends on the climate. I mean, if I'm in Florida, you know, I'm using all electricity and I'm probably not using heat that much either. I'm using AC. But if I'm in North Dakota, I'm killing out some boilers and some oil and some gas and, you know, it's more efficient to use that up there. I think it's good. We'll save that other question for next time. All right, that's it. Uh, thank you for watching. Make sure you send in your questions and do not forget, check us out on Facebook, Twitter. Uh, we have articles, videos, almost up to 100 videos now on YouTube. I mean, it's crazy the amount of content that is free out there for you, but we are here for you and we want to educate you on the things that matter the most, and that is your home and your energy usage.
