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January 18th, 2024
Here at Fire & Ice, we’ve talked with thousands of customers about how to meet their unique heating needs. One important subset of those folks is the first-time home buyer who’s in the market to buy a furnace.
A lot of the new homeowners don’t have a clear idea of what’s providing heat. They will shop for a furnace only when the existing one emits its last ounce of warmth.
All of a sudden, they face a tough decision. Which HVAC contractor should you trust? Which brand of furnace is best? Which estimate should you choose: the cheap one from a company you know nothing about, or the more expensive one that your neighbor used?
What type of furnace is greenest? The one with the best comfort level? Is springing for a top-of-the-line model with superb efficiency going to save you enough on your energy bill to be worth it? How well will it fit into your existing HVAC system?
This article examines the types of heat sources that are available, and their advantages and disadvantages. By the end, you should have an idea of what your first furnace purchase might entail. After all, we don’t want you to make the wrong choice and wind up paying for a system that isn’t right for your home.
No one deserves to be uncomfortable.
Read more: The Complete Guide to Home Furnaces
Can You Heat Your Home with Only Space Heaters?
Portable heaters are good for keeping a smaller space comfortable, but they are highly inefficient. It costs a lot of money to run them, and their range is limited. If you want another space to be comfortable, you need to move it or buy another one. That raises the energy bill.
The electricity that powers an “energy efficient” (as they are often marketed) space heater could come from any number of inefficient fuel sources, such as oil or coal. In other words, while these heaters are efficient at converting electricity into heat, they’re actually among the least energy-efficient ways to heat your home.
Electric space heaters are also not the safest option for staying warm when the temperature drops. According to the National Fire Protection Association (NFPA), space heaters account for 43% of home heating fires and 85% of home heating deaths.
Central Heat Is a Whole-Home Solution
A better comfort solution is a full-split system, with a heat pump or air conditioner outside, and a furnace or air handler indoors. The big advantage is that you can heat the house to a consistent temperature.
It’s more efficient and a lot more comfortable. It’s also a more permanent solution.
You can go up to 140,000 BTUs and higher on some furnaces, and central heat will be your best bet for some of the cold snaps we get in Central Ohio. And you can always add a portable space heater or two for problem areas.
Can a Heat Pump Keep You Warm in the Winter?
At around 40 degrees, heat pumps will start to derate. Variable-speed units can go quite a bit lower, but once they start losing effectiveness, it’s not a bell-curve drop-off. It’s a harsh, straight line down, and that’s when the emergency heat would need to kick in.
That’s when it gets really expensive. Emergency heat is very heavy use on your electricity. That heat is provided by heat strips that would be in the electric furnace or need to be installed in the air handler.
I’ve been in homes that didn’t have heat strips. They are an add-on. Other contractors may skip the emergency heat; we always install it in air handlers or find another solution.
A heat pump will have a hard time dealing with temperatures below zero. Pairing it with a gas furnace is the best way to cope with that. The furnace can take over when the heat pump can’t provide adequate warm air.
What Size Furnace Should You Have?
All HVAC companies would recommend the correct size furnace for your home, install it according to the manufacturer’s exact specifications, stick around long enough to ensure it’s working as it should, and ensure your complete comfort.
Sad to say, it isn’t so.
There’s an old wives’ tale that tells about how contractors used to measure a home’s heating requirements. They would stand on the sidewalk in front of the house and hold up their hand. If three fingers covered the length of the house, they would recommend a three-ton system.
Sound far-fetched? It’s not. Nor is it uncommon for a contractor to use only the square footage of the home to make their estimation.
The only way to get an accurate size recommendation is through a Manual J load calculation. Yes, it factors in square footage, but it also accounts for the number of windows and doorways, the number of occupants, attics and basements, insulation, and more.
And if you receive an estimate for a furnace size that doesn’t come from this method, please find another contractor who will do the job right. A furnace that isn’t the correct size will wear out faster, provide uneven temperatures, and cost you dearly when it comes to repair bills.
Read more: Choosing the Right Furnace: 3 Factors that Determine Your Options
Electric versus Natural Gas Furnaces
If you want a natural gas furnace, you’ll have to get ahold of your local provider. They will help you determine how to get a line and meter to your house. If there’s no main line on the road, you’ll have to settle for propane.
We generally recommend a hybrid system, a dual fuel. That means you’re using electricity as one source, and gas or propane as the second.
Typically, we see heat pumps paired with gas furnaces. Your heat pump will keep you comfortable three-quarters of the year, and the furnace would take over when the call is for emergency heat.
Furnace Types: Blower Motors
HVAC is all about air distribution. In every furnace, there is a blower motor responsible for collecting air from the house, filtering it, and then pushing the conditioned air back throughout the ductwork. It also has a job in the summer; that same blower moves cool air generated from your air conditioner or heat pump.
Modern furnaces come equipped with one of two types of blower motors: single-speed or variable-speed. Single-speed blower motors move air at one speed.
Furnaces equipped with variable-speed motors are able to increase and decrease speed anywhere from 0 to 100%. This technology can help eliminate hot and cold spots or uneven temperatures, allows for better air filtration, and are often much quieter. They are also the most costly.
Read more: What Are the Benefits of a Variable-Speed HVAC Motor?
Furnace Types: Efficiency
Another factor to consider when choosing a gas furnace is its efficiency. Furnace efficiency is measured by an Annual Fuel Utilization Efficiency or AFUE rating. It’s the percentage of heat your furnace produces.
A standard efficiency furnace, for example, will convert up to 80% of its fuel consumed as heat. The remaining 20% is exhausted as waste. A furnace is considered high efficiency when its efficiency is over 90%. Some models boast an efficiency rating as high as 98%. That means out of every dollar spent on fuel, 98 cents is going towards heating your home.
The higher the efficiency, the more you’ll save on your energy bill. It will also increase the initial cost of the unit, so the homeowner has to decide whether the upfront cost is worth it.
Furnace Types: Single-Stage Gas Valve
Furnaces can be further broken down by their gas valves, which are classified by “stages.” A gas valve regulates how much fuel your furnace uses to heat your home at any given time. The first type is the single-stage gas valve.
When it turns on, 100% of its capacity goes towards heating your home, even on days with milder temperatures. The furnace will work at full throttle whenever the temperature dips below your thermostat’s set point.
The primary benefit of single-stage furnaces is they are inexpensive, and their technology has been around the longest. Single-stage furnaces typically come equipped with fixed-speed electronically commutated motor (ECM) motors. They’re ideal for homeowners with smaller square-foot homes or homes without comfort concerns such as uneven temperatures or hot and cold spots in the winter.
Furnace Types: Two-Stage Gas Valve
The second type is the two-stage gas valve, which has two capacities. When it first kicks on, it’ll start in its first stage and use about 60 to 70% of its total capacity. Then, when more heat is needed, the furnace goes into its second stage using its full power.
Most of the time, your furnace will be in its first stage, which offers greater fuel utilization. It also provides more even temperature control because your system will run longer in its lower stage, allowing for more air circulation. The more the air circulates, the more even the temperature in the home.
Regardless of which variation you choose, two-stage furnaces are great for homeowners who suffer from uneven temperatures between floors or hot and cold spots between rooms.
Furnace Types: Modulating Gas Valve
The third type of gas valve is called modulating. They can increase or decrease the amount of gas being used in small increments. For instance, on milder days, it may use only 40% of its total capacity, but as the demand for heat increases, the gas valve will incrementally open up.
It’s like cruise control on a car. It makes tiny adjustments to keep the temperature level. And cruise control is when you get the best MPH. It’s the same concept for your furnace, except you replace MPH with efficiency. It’s easy to see the potential energy bill savings.
When you pair the modulating gas valve with a variable-speed blower, you’ll have a furnace that’ll be able to keep you comfortable all winter long. It’s capable of maintaining the temperature inside your home within a half degree of the thermometer’s set point regardless of the temperature outside.
Do You Need to Get a New Thermostat When Buying a New Furnace?
If you’re buying a new furnace, you don’t necessarily have to replace the thermostat, unless you have an old mercury-style that spins. Those are not up to code, so they need to be replaced.
We do recommend replacing it because we want to control the whole system at once.
If you’re thinking about adding a humidifier or dehumidifier, and you want to control it from the thermostat, you would have to run another wire.
Read more: HVAC Thermostats 101: Installation, Features & Controls
Heating with Ductless Mini-Splits
Ductless mini-splits are an ideal solution for certain heating and cooling problems. They give you a high level of control over your home temperature while reducing energy bills.
We rarely see a home in which they are the only source of heat. They are used in more of a per-basis situation. If the main bedroom or a bonus room above the garage or an office where you spend a lot of time needs additional heat but the rest of the home is OK, a ductless system could be the perfect solution.
Read more: Ductless Mini-Splits: A Comprehensive Cost Breakdown
They’re super-efficient, so the electric bill won’t go up drastically. And they cool as well as heat. They will provide better comfort and be more cost-effective in the long run. It’s an investment that you’ll be happy with.
I was in one house that had baseboard heating and window air conditioners. There were no ducts, and they wanted a new system. Without ductless mini-splits as a heating-cooling option, they would have to do a full remodel, with several thousand dollars spent in other areas (woodworking, drywall, ductwork).
One major downside to ductless mini-splits is: The initial outlay is higher. The cost of making a home that’s heated entirely by ductless is not inexpensive.
Another downside: There’s another piece of HVAC equipment you have to maintain. That means more maintenance every year. If something goes wrong, someone has to come out and fix it. But for a long-term home, it can be a great solution.
Does the Brand of the Furnace Matter?
The brand seems to matter more to homeowners than to us. A lot of new homeowners tend to focus on the brand. It’s like that with cars, too. Honda’s the best. Ford’s the best. In reality, no one really makes a bad car. It’s more about how you maintain it.
The thing that’s most important when buying a furnace are the HVAC contractors that are installing it, making sure they’re following best practices, they’re commissioning it properly, making sure you get the best comfort and efficiency,
A cheap furnace properly installed and maintained can have a lifespan every bit as long as a more expensive model.
Will a High-Efficiency Furnace Save Money?
I always ask homeowners, “How long do you plan on being in your home?” There’s a small return on investment with an expensive furnace. The energy savings will never match the initial investment, no matter how long you’re there.
But if you plan on being in your home for 20 years, you’re going to want something that’s more efficient and comfortable compared to if you’re only going to be there three years, when you don’t want to put money into the high-efficiency furnace.
Read more: Will a High-Efficiency Gas Furnace Save You Money?
Buying the Right Furnace
Sometimes I meet with a homeowner who has multiple comfort concerns concerning his indoor air quality - allergies, excessive humidity, huge temperature differences between floors - and want all of them solved but isn’t planning on staying in the home for very long.
I’m more than happy to sell them a high-end system to alleviate those problems, but I’ll be upfront with them and let them make the call on whether to make the investment. I’ll play devil’s advocate, and discuss the pros and cons.
Maybe we can find a partial solution. The prospective furnace will be better than what they have, but it’s not going to solve every problem.
And if you’re a first-time homeowner in the market for a furnace, we hope that we’ve given you some things to think about while you ponder your decision. If you’d like to talk further with us, fill in your zip code in the graphic below to see if you’re in our service area.
We look forward to hearing from you.
