Is a Natural Gas Furnace Right for Your Home?

Book Resting on Chair With Fire in Background

Fires are Nice, But We Generally Rely on the Natural Gas Furnace for Consistent Warmth.

For those of us who don’t have underground propane tanks already installed in the yard, our heating options generally boil down to two options. Gas, or electric. While advocates of both sides can come up with a laundry list of reasons to choose one or the other, many homeowners opt for a natural gas furnace. That’s what we’ll be discussing today.

How do you go about picking a home furnace replacement, and how do you go about caring for it once the unit is installed? After reading through below, you should be able to answer both questions confidently. Here we go!

Important Factors to Consider

When selecting a replacement heater, not every homeowner needs a high-dollar, high efficiency gas furnace. While natural gas furnace BTU rating is important, there are so many other factors to consider, such as size, lifetime expectancy, brand, manufacturer’s warranty, and features. Your family’s future plans (selling the house or staying indefinitely), should also factor into your decision.


How Many Years Does a Furnace Last?

On average, furnaces will function between 15 and 20 years. If you want to keep your furnace at peak efficiency for its full lifespan, that will require some dedication on your part as a homeowner. Once your unit hits the 15 year mark, you should start researching for your next replacement.


How Do I Size a Furnace for My House?

Sizing your new natural gas furnace is actually easier than you may think. Start by taking the square footage of your home and multiplying it times 35 (or 30 if your home has strong insulation). Let’s say your house is 2,000 sq ft in area.

2,000 x 30 = 60,000 Btu needed for your home. Write this number down!


Each furnace product is rated in Btu (British thermal units), which is a way of measuring a unit’s heating power. The furnace also comes with an efficiency rating, which determines how much of that heating power is used effectively. Let’s use a couple examples.

75,000 Btu (input) x 0.8 efficiency rating = 60,000 Btu (output)

60,000 Btu (input) x 0.95 efficiency rating = 57,000 Btu (output)


Both of these theoretical furnaces fall within the acceptable range for the home’s heating needs. That range extends 10 percent below the required Btu and 20 percent above. In other words, for a home that requires 60,000 Btu’s for heating, the acceptable range is 54,000 – 72,000. If you go too low, you won’t be able to heat the house. If you go over, you’ll suffer significant energy losses.


What is the Best Gas Furnace?

According to a Consumer Report conducted from 2011 to 2016, American Standard, Ruud, and Trane are considered most reliable by homeowners. That doesn’t mean you shouldn’t consider other brands, but these three are certainly worth examining. After brand, you should consider efficiency as well. While higher efficiency ratings can save you money on gas expenses, many homeowners have to install special ventilation to accommodate the most efficient models.

Finally, you need to examine the features that are available with each model. Some offer little more than an on/off switch, while others can provide variable speeds and heat production. Talk with your HVAC specialist about which model would work best for your home!

Natural Gas Furnace Issues

Replacing the Cover on a Gas Furnace's Control Box

There are Several Challenges Your Furnace May Face Over the Years, Including Reduced Efficiency.

There are some common malfunctions that your gas furnace may start to exhibit with age, such as:

  • Short cycling (turning off and on frequently)
  • Unstable pilot light
  • Clogged filters
  • Faulty thermostat readings
  • Damaged limit switch
  • Expired ball bearings

While we don’t have time to talk about all these problems today, each one can drastically affect the functionality and efficiency of your furnace. Be sure to talk with an expert if you notice strange noises, hear your system short cycling, or feel the symptoms of carbon monoxide exposure.

The Heat Exchanger

What are the Symptoms of a Bad Heat Exchanger?

The heat exchanger is one of the most active parts in your furnace, absorbing heat from the burning gas and transferring it. It’s made of a durable metal to conduct the heat effectively, but this tough metal starts to crack after years of burning and cooling. A cracked exchanger typically won’t perform as efficiently, so your furnace will have to work harder to raise the temperature.

A damaged exchanger may also allow carbon monoxide to leak into the house, which can cause dizziness, irritate lungs, and even asphyxiate people (with prolonged exposure). You may also notice your exchanger starts to rust when it’s time to replace it. Thankfully, your exchanger will last one or two decades before it requires replacement.

Cleaning Your Furnace

Natural Gas Furnace Cleaning

Cleaning your gas furnace is actually fairly simple.

  1. Start by turning off your furnace and closing the gas flow. Your first step should be to check the filter. If it’s a reusable one, clean it off with a hose and allow it to dry before placing back in the furnace.
  2. Next, open the main compartment of your furnace. Make sure you wear gloves, just in case. Take a shop vacuum with a smaller nozzle attachment. Vacuum up dirt and dust in the main compartment, but be sure to take note if you see any soot. This could be a symptom of a bad exchanger.
  3. If you want to clean out the blower, carefully remove connecting bolts. You may have to get past a control panel to do so. You can clean out the blower fan with a small brush and vacuum.

Schedule Your Natural Gas Furnace Replacement!

Need help installing a natural gas furnace in your home? Our team at Metro Air & Heat would be happy to help you find the perfect model for your home and budget! Our certified experts have years of experience, so you can trust them to install your appliance correctly for lasting use. Give our team a call today at (817) 945-3601.