Choosing the Right Size Furnace – Bigger Isn’t Always Better

Updated: December 14, 2023

In a lot of ways, bigger is better: pizza, hotel rooms, beds, budgets, the list goes on. But when it comes to your furnace, the opposite could be more beneficial for your home. Are you a “proud” owner of a big furnace, disappointed in its performance? You might be experiencing some very common problems like high utility bills, inconsistent temperatures throughout your home, or too-short heating cycles.

When choosing the right furnace size in Des Moines, IA, taking things down a notch or two could be all you need to get the ideal temperature during even the most frigid winter days. Here is why an oversized furnace might be more problematic than an undersized one.

It makes your house less comfortable

Would you believe us if we told you an oversized furnace might not warm parts of your home?

When your powerhouse of a furnace kicks into gear, some areas will warm up, no doubt. But those places will likely warm too quickly to the point where it’s uncomfortable (or just downright hot) before the thermostat can even read the temperature. As this happens, the furnace will turn on and off frequently in response to the quick spikes and drops in heat, and this is especially true for poorly insulated houses. Many oversized furnaces shut off before the heat can ever reach some parts of your home, making a sauna at one end of your home and a freezer at the other.

It will be less efficient

Your furnace won’t reach its peak efficiency until the air coming out has reached a steady level, and this is regardless of the size you choose for your home. Furnaces use the most amount of energy when they are starting up and shutting down, similar to how your car engine works.

But when your furnace is too big, it spends hours just to warm up, using a significant amount more energy than its smaller counterparts. Considering the amount of energy used, you would hope that your whole home would be a consistent, snug 70 degrees, but because of the nature of the machine, you won’t find that kind of performance.

It has a shorter lifespan

Let’s think about two cars: The first car will get from point A to B as quickly as it can, starting and stopping, making sharp turns, and accelerating or decelerating as needed, but it will definitely get to point B faster than the second car (after all passengers have gotten motion sickness).

The second car will get from point A to B while keeping a much steadier speed with an overall smoother ride. It takes a little longer, but regardless, arrives at point B just fine. Which car do you think will have a healthier engine? The first car might blow out its engine and use more gas than needed, but the second car takes the cake.

This is precisely how you should think about the longevity of your furnace. As your oversized furnace constantly is shutting on and off and on and off, that puts a lot of excess stress on it as it runs throughout its lifetime.

The Bottom Line

See if you should switch to a smaller furnace. With a smaller furnace, you’ll find it’ll run almost the whole day at a steady rate throughout the whole winter season, keeping your house at a steady 70 degrees. Even a slightly undersized furnace will accomplish the job the majority of the time.

Taking things down a few sizes will more than likely solve some of your common heating problems like too high of a utility bill while half of your house is blazing and the other half is an icebox. In an ideal world, you would have a reliable furnace, a reasonable utility bill, and a consistently toasty home. With a smaller furnace, you could have that. So give your HVAC guy a call and get an assessment of your house’s heating needs. You might be surprised at the size of furnace your house actually calls for. After all, don’t the best things come in small packages?

Contact us today for heating installations in Des Moines, IA!

Author: Joe Tollari