We are heading to the cooler and colder time of the year. Your furnace is 20 years old and it is on its last leg. Time to replace it. You’re thinking if you go to a bigger furnace it will be more efficient. Not necessarily.

Unless your previous furnace was undersized for your home, getting a bigger and more powerful unit will likely cause more problems and not really help to improve the comfort of your home. Below we explain the common issues an oversized furnace will cause, and why getting one, if not really required, is a very bad idea.

The Perfect Size Furnace

A perfectly sized furnace will probably run almost all day on the coldest day of the year, and it might not get the house up to 70 degrees about 1% of the time during the winter. No joke. That would be a perfect system. For 1% of the time during winter, you might need to put on a little extra clothing. No big deal.

Many people complain about one part of the house heating up more quickly than others and sections that are hotter. It’s a common issue for even people with well-balanced furnaces.

But If You Oversize The Furnace…

Things can become really problematic. Those slightly warm rooms will become uncomfortably warm. It’s also possible that rooms of your home will remain cold if your thermostat is located in one of those warmer rooms.

Do You Know…

An oversized furnace will heat your home less efficiently than a perfectly sized unit would. That’s because it doesn’t reach peak efficiency levels until AFTER it’s gone through the warmup phase.

The Downside

The downside of too much power in your furnace is it will get your home up to the set temperature too quickly. No quick isn’t always better. Then if the temperature falls, you’ll get another blast of heat. The excessive blasts will make it switch on and off more often, which wastes energy because the unit won’t spend much of its time running at peak efficiency due to it being in the warm-up phase so much of the time.

Oversized furnaces are known to have a problem called short cycling. This is when the furnace turns off too quickly before the house even reaches its proper temperature, which happens because the furnace overheats.

A furnace that is constantly cycling on and off will have a decreased lifespan. Heat exchangers on furnaces are made with metal that constantly heats and cools. This repeated heating and cooling is not a good thing for the heat exchanger, which will end up failing.

It’s just not healthy for a furnace to turn off and on too often. If you get an oversized unit, it will cycle more frequently than if you had the right-sized one. That often means that it will fail sooner than the right-sized unit will.

An oversized furnace will likely overheat as well which can damage important components. Additionally, it generates more heat than can be used up and that heat builds up during operation. This can build up to just too much heat and the unit reaches dangerous temperatures. It’s then shut off to protect the house.

What Do You End Up With?

A home that isn’t warming properly and eventually, a damaged furnace.

That’s why you need a professional to calculate what size furnace would be perfect for your size home. Greer’s Heating & Air is here to assist you. They are the professionals you can trust so you have the perfect heating system for your home!