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Wall Heating & Air Conditioning Blog

Does Size Matter When You Get a New Heater?

jets-of-a-furnace-firingIf you’re looking for a new furnace this time of year, then you understandably have a lot on your plate. And with options to consider like what fuel type to use, the AFUE vs. HSPF ratings, whether to go with electrical or gas, etc. you may be tempted to go with the first furnace that fits your budget just to get the process over with.

However, we really do not recommend rushing into this type of purchase, for quite a few reasons. The most important of these reasons is—size matters! If the furnace system you have installed in your home is either too large or to small, you’ll be unpleasantly surprised by how quickly things will turn sour for you.

“Wait, a Furnace Can Be Too Big?”

Yep! And furnaces that are too big for the homes in which they’re installed generate too much output. This will often result in the thermostat shutting down the furnace before it’s had the opportunity to complete a full heating cycle—this process is known as short-cycling.

Furnaces of all sizes are designed to function in cycles, where they generate a set amount of output over a set period of time, before resting. If the furnace shuts down before it can complete a full heating cycle, it will start to have negative consequences.

The various components of your furnace will begin wearing down more rapidly than they were meant to, and the furnace won’t be able to actually heat the home efficiently, since the thermostat will keep cutting it off. The overall lifespan of your furnace may even be shortened, if it’s allowed to short-cycle long enough.

What Happens When a Furnace Is Too Small?

An undersized furnace, understandably, won’t be able to generate enough heat to keep your home comfortable, so it will stay operating for much longer than it was designed to, in order to compensate.

This is pretty much the exact opposite problem from what happens if the system is too big—but in the end, it will have the same results. Your furnace will have increased wear and tear, culminating in a shorter lifespan.

Proper Furnace Sizing

Properly sizing a furnace is about more than just getting the right physical dimensions, although that is, of course, an important part of the heating installation process. Our technicians look at the overall output of the system in relation to the size of your home, but we also look at things like the type of insulation you have, if you have high ceilings, how many windows and doors are in your home, and if you have any home performance opportunities such as drafty windows and doors.

Properly sizing a furnace, or any HVAC system for that matter, is not something to leave to an amateur or the average homeowner. Our technicians are specially trained and experienced for this kind of work, and we’re happy to help!

For professional HVAC service in Duluth, GA contact Wall Heating & Air Conditioning, Inc. today and schedule an appointment.

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