Owner Jared Grier talks about forced hot air furnace systems and their benefits, including energy efficiency, integrations with other HVAC components, and more.
John Maher: Hi, I am John Maher and I’m here today with Jared Grier, owner of Cape Cod Heat Pumps, an HVAC and electrical contractor in Marstons Mills Massachusetts on Cape Cod focused on detail, quality and professionalism. Today, our topic is the advantages of a ducted forced hot air furnace system. Welcome, Jared.
Jared Grier: Thanks for having me, John.
Furnace Energy Efficiency
John: Sure. So Jared, how does a ducted forced hot air system compare to other heating systems in terms of energy efficiency?
Jared: Yeah, I mean, if we’re talking natural gas or propane, these systems are quite efficient, upwards of 97% efficient. Essentially that means if you pay for a dollar’s worth of fuel, whether that be propane or natural gas, you’re getting 97 cents worth of heat out of it. So we’re darn close to being near 100% efficient. So they are very efficient.
Variable Speed Blower Motor
The new furnaces also have features, one feature we call a variable speed blower motor. What that means is the motor in it that we’re using to move the air across our heat exchanger and throughout our duct work, it’s more efficient, so it’s moving the same amount of air while using less electricity. So oftentimes that can be one of the hidden costs that people don’t necessarily think about when they’re heating their home, especially with natural gas, because obviously they see the gas bill and they associate that with their heat, not their electric bill. So that’s one of the features.
Multi-Stage / Modulating Furnace
Something else that also is somewhat of an energy efficiency benefit is what we call multi-stage or modulating furnaces. What this essentially means is a day like today where it’s about 40 degrees outside, so not as cold as we’re going to see, but also you’re not opening your windows and enjoying the nice cool air outside, but that system is sized to heat that home when we hit the worst temperatures we might expect, which would be about zero degrees here on Cape.
So what that means is, that furnace just inherently is oversized, right? Because we need to size it for those worst case scenarios. So those modulating or multi-stage gas valves will allow that unit to really adapt to the needs of the house versus overheating it really quickly by throwing all the capacity of the system.
So the way it works, if it’s a two-stage furnace, the way we work here is we basically lock it into the first stage, which is about 60% of capacity of that furnace for the first 15 minutes. If the thermostat after 15 minutes is still calling, that furnace is going to recognize it and say, “All right, let’s go to our second stage,” which is a hundred percent capacity of that. In doing so, again, we’re going to more gently heat up the house. We’re not going to be throwing the full capacity, potentially overshoot the thermostat, and you get these hot/cold scenarios where the thermostat’s got the call, throws the heat, then you get hot, and then it’s got to cool off. So they can help compete with that as well as help lower your utility bills.
John: Is it smart enough to know if the temperature is 60 degrees and you’ve just set the thermostat at 70 that it needs to go at a hundred percent to really get it up to there? Or does it still just, for the first 15 minutes it’ll gradually heat it up and then kick into the higher gear?
Jared: Yeah, so the multi-stage, the two-stage furnaces, generally that’s going to be based on just operation time, right? You’re going to set some sort of arbitrary number. Some of the more advanced modulating furnaces will actually increase or reduce their fire rate based on the needs of the house. So these systems, in a way, are intelligent and they can learn the space, learn how long it takes to heat up the space so that they can moderate their operation based on what it’s learned from heating the home over six months to a year. So varying degrees of intelligence that these systems have that they’ll operate. But for the most part, most of the systems we’re putting in are just those two-stage furnaces.
Integrating a Furnace with Other HVAC Components
John: Can a ducted, forced hot air system be easily integrated with other HVAC components, like central air conditioning, for example?
Jared: Yeah. I mean, that’s actually a very common scenario here on Cape. 50 years ago, 20 years ago, when a lot of these systems and homes were built, you didn’t need air conditioning. It was a cooler climate that we had here in the summer months, but now people are finding that we’ve got a bit longer, warmer, more intense summers. So what’s really nice, these people that already have furnaces in their homes, we’ve already got that infrastructure to be able to add air conditioning easily into that home. So if you’ve got a furnace, odds are you can add air conditioning to that system, no problem.
John: And you could do that with a central air conditioning system, or can you utilize a ductless system as well that integrates with the ducts that you already have in your home for your heating?
Jared: Yeah, so I mean, you’re probably going to go with something more conventional. The mini splits, the ductless, is more of its own style system that’s going to be standalone, but we can do what we call dual fuel systems, which will utilize heat pump technology with that existing ductwork, but maybe not all the time. Maybe people don’t want to fully decarbonize or fully depend on heat pumps.
So what’s nice about dual fuel is we get the best of both worlds. We’re going to optimize the efficiency and cost-effectiveness of the heat pump down to about 40 or so degrees, and then after that we’re going to kick in that natural gas furnace for those cooler times of the year or just even those cooler days and utilize the more efficient gas furnace at that point.
Indoor Air Quality Furnace Add-Ons
John: What about indoor air quality? Are there any sorts of add-ons or accessories that you can add into a ducted forced hot air system that will help improve the indoor air quality?
Jared: Absolutely. I mean, there’s almost endless options nowadays, but the one reason that I’ve always advocated for forced air is the fact that we have many more options when it comes to indoor air quality. We can do everything from humidification to dehumidification. Then there’s air filtration, whether we go with a MERV 13 or a HEPA-style filter. There are UV-style lights that can help keep your evaporator coils clean. There are iWave devices that can be used to help clean the air as well. So our options with forced air systems is pretty wide and varying, and we can really customize that system to each individual person’s needs.
Eco-Friendly Furnace Options and Environmental Sustainability
John: And then finally, how does a ducted, forced hot air system contribute to environmental sustainability? And are there eco-friendly options or features that are available as well?
Jared: Well, as I said, most of the modern furnaces are already more efficient. Right there that is obviously going to help the environment by taking something out that’s 80% efficient and putting in something that’s 97% efficient.
John: You’re not just burning those fossil fuels for nothing and not getting any heat out of it.
Jared: Exactly. I mean, to give you an idea how efficient these furnaces are, we actually don’t even vent them through chimneys or anything like that. These are what are called direct vent appliances. So we’re actually venting with a plastic-style material right to the exterior of the house. And quite frankly, if that furnace is running, I can put my hand right in front of that flue without even having to worry about burning myself. So it’s really showing you how much of that heat that we’re capturing out of those flue gases or that flame and returning to the house. So obviously just that alone will help.
Then as we already discussed, there’s some dual-fuel applications, which will allow people to utilize both heat pumps and furnace’s fossil fuels. Through the Mass Save program, there’s some rebates. There’s the Heat Loan program to do that as well. So we’ll do these systems where we’re not touching the furnace, but maybe the customer wants AC, and then we’ll say, “Hey, do you want to reduce some of your heating bills as well?” And they say, “You can do that as well while you put in AC?” And we can. So we’ve got a lot of options that can help improve your [carbon] footprint.
John: All right, that’s really great information, Jared. Thanks again for speaking with me today.
Jared: Thanks, John.
John: And for more information, you can visit the website at ccheatpumps.com or call (508) 833-HVAC. That’s (508) 833-4822.