How Furnaces Work

October 31, 2019

By Comfort Air

How Furnaces Work

Have you ever noticed that your furnace seems to stop working on the coldest day of the year? Thankfully, this is not the case for all furnaces. We are busy repairing and replacing furnaces throughout the cold season.

Furnaces 101

There are two types of vents in your home. One set of vents is connected to the “intake” side of your furnace, which is where the furnace draws air in. The air is then blown across the heat sources of your furnace, and then distributed within the ducts to all of the other vents throughout your home.

Choosing a new furnace can be an intimidating process. There are nearly 100 different brands and thousands of different models. They include budget models, mid-efficiency models, and high-efficiency models. Repairing and/or replacing a furnace is NOT a do-it-yourself job. HVAC installation should be completed by a fully qualified and licensed HVAC contractor, as the process involves handling high-voltage electricity, plumbing, and gas lines, and in some cases, venting combustible gases or refrigerants.

Things to Consider

  • Size - There is nothing more important than proper sizing when it comes to furnaces. One of the biggest mistakes other contractors make is assuming that your previous furnace was properly sized. Load calculations must be performed to determine the proper size. Any contractor who says “We’ll do it before we start the job” is not doing the load calculations. We do not give you a proposal until all the load calculations are done.
  • Fuel Source - Electric, gas, propane, or oil are the possible options. Gas is the most popular. Oil and electric are typically the most expensive. They all have their benefits, so we are happy to discuss the options with you beforehand.
  • Unit Type - High-efficiency units are typically more expensive up-front, but in the long run they cost less. Keep in mind that high-efficiency may mean higher complexity.


Manufacturers offer discounts and rebates at certain times. We will definitely let you know if there are any available. Some units run quieter than others, so this could be a consideration for some homeowners. With more than 1,000 different models, we can find a furnace that matches your budget and your requirements. When you are looking for an “HVAC service near me,” look no further than Comfort Air.

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