Why do I need a Furnace in the Summer?...

...Aren't those just used to heat your house?

Well, the simple answers is "Yes", and "No".

This is a question, or something similar, that anyone who works with heating and cooling equipment has been asked, probably more times than they can count. And as the saying goes, "There are no stupid questions." With this post I am going to try and provide a simple and understandable explanation.

Let's start by explaining what is inside a furnace. If you were to look inside your furnace, you would notice its two major components: the Blower and the Heat Exchanger. There are other things in there to control how and when the blower and heat exchanger work, but for our discussion we are only going to focus on these two parts.

The Blower, or fan, or squirrel cage, is basically a fan that draws air from inside the house through the return duct system, then blows it back into the house through the supply duct system. The Heat Exchanger is a series of sealed metal compartments that are heated with a flame. When these sealed compartments are hot, air blows past them and transfers that heat into your home.

How is that for a simple explanation?

So, why do you need a furnace in the summer?

Well, the explanation I gave only told half of the story. Just because the furnace contains a Heat Exchanger doesn't mean it only works when the heat exchanger is hot. During the cooling season the Heat Exchanger is basically switched off, and only the fan operates.

So in the summer, instead of the Blower transferring heat from the Heat Exchanger into your house, it moves air across your evaporator coil where heat from your home is removed, thus making the air cooler and reducing the temperature in your house. (I will explain this process in greater detail in a later post.)

Now, to sum things up and answer the original question, you need a furnace in the summer because it contains the fan that moves the air through your home that the air conditioner has made cooler. If you didn't have a furnace, your air conditioner could run forever, but you would never feel its effects.

I hope this explanation is helpful. If you have any questions, I am more than happy to answer them. Just shoot me an e-mail, or give me a call, and I will see what I can do.

Thanks! And stay COOL!