The furnace is a heating system that provides warmth and comfort during the winter months. It’s not just your home’s primary source of heat; it also helps control humidity in the air, regulate air quality, and remove dust from the air. There are many different types of furnaces with various features available.

Did you know that furnaces work year-round to keep your home warm? During the summer months, the air conditioning unit circulates cooled air through the house and returns to the AC unit, where it begins the process again. The filter catches any dust or particles in the air and helps keep the AC unit running smoothly.

In the winter, the furnace reverses the process and heats the air, then sent throughout your home. The furnace filter catches any dust or particles in the air and keeps them from entering the furnace itself. This helps to ensure that your system runs efficiently and doesn’t get clogged up.

Types of Furnaces

There are four main types of furnaces: gas, electric, oil, and propane. The type of furnace you have will depend on the fuel source available in your area.

Gas Furnaces

Gas furnaces are the most popular type of furnace, and they work by burning natural or propane gas to create heat. The warmed air is then circulated through the home’s ductwork. Gas furnaces require a connection to the home’s fuel source and need electricity. There are two types of gas furnaces: forced air systems and hot water boilers.

Electric Furnaces

Electric furnaces function similarly to gas furnaces. It burns an electrical current to generate heat, but rather than heating the surrounding air like, with gas furnaces, the heat is transferred to a radiator system in your home. Electric furnaces are usually more expensive than gas ones, and they can be less efficient because an additional heating source isn’t generating warmth at all times, like with gas furnaces.

Oil Furnaces


An oil furnace heats water from an external tank, which flows through pipes to your home’s radiators. Oil furnaces are similar to electric ones in that they require electricity for the heating process. Unlike electric furnaces, oil systems can also function as backup heaters if there is an issue with other types of furnaces or power sources.

Propane Furnace

A propane furnace heats the air in a similar way to gas furnaces. Propane is then sent through the home’s ductwork, where it heats the air inside your house before flowing back outside again.

Propane systems are usually smaller than other types of furnaces. They can be more efficient because propane burns hotter than natural gas, oil, or electricity (similarly to how a gas stove works).

Furnace Parts and Functions

The major components are the blower, burner assembly, heat exchanger, and filter. Furnaces also have different functions, depending on what type of system they are. For example, gas furnaces require electricity to start up the burners, producing warmth by burning natural or propane gas (similarly to how you would start a grill). The blower then kicks on and circulates the warm air through the home’s ductwork.

Electric furnaces have a heating element that is similar to an electric stovetop. When the furnace turns on, the heating element begins to heat up and produces warmth, which is transferred to the radiator system in your home.

How Does a Furnace Work?

When you turn on your furnace to heat the house, this is what happens:

The blower starts to circulate warm air through the home’s ductwork. The burner assembly then ignites and heats a gas or electric current (depending on which type of system you have) inside it before sending out hot air into the heat exchanger, where it will warm it. The warmed air is then circulated through the home and returns to the furnace, beginning the process again.

The filter catches any dust or particles in the air before entering the furnace and causes damage. It’s essential to change your furnace filter regularly (every three months is recommended) to ensure that your system is running at its best.

Which Furnace Should You Choose?

You will need to look at several factors before deciding which type of furnace is best for your home. The most critical factors are climate, fuel source availability (natural or propane), and budget. However, you should also consider maintenance costs over time since some systems may require more upkeep than others to keep them working correctly.

Installation and Maintenance

Installing or replacing a furnace is a big job that a professional should only do. A furnace installation includes running new ductwork, installing the furnace itself, and connecting it to your home’s fuel source.

Furnaces also need regular maintenance to ensure they are functioning correctly. This usually includes cleaning the furnace filters, checking the thermostat settings, and ensuring that all vents are open and transparent.

How Can You Measure Furnace Efficiency?

If you want to measure the efficiency of your furnace, you can use a tool called a furnace Efficiency Rating (FER). This rating is calculated in terms of Annual Fuel Utilization Efficiency (AFUE), and it tells you how much of the fuel used to heat your home is turned into warmth.

The higher the AFUE rating, the more efficient the furnace is. Most gas furnaces have an AFUE rating of around 80-90% whereas electric furnaces range from 95-100%.

Now that you know how a furnace works, you can be more prepared when it’s time to replace or upgrade your system. Keep in mind the different types of furnaces available and what might work best for your home and climate. And as always, be sure to consult with a professional before making any significant decisions.

What Is the Lifespan of a Furnace?

The average life span of a furnace is 15-20 years. Furnace manufacturers typically warranty their systems for around this amount of time, but if you find issues with your system before then, don’t hesitate to contact them right away. You can fix most problems without too much hassle, and the company may offer you an updated part at no cost to resolve the issue.

How Much Does a Furnace Cost?

The average price of a new furnace is around $1,500-$6,000. This will vary depending on the size and type you need, as well as any discounts or rebates your local utility company may offer. For example, some companies allow customers to receive up to $300 rebates for purchasing high-efficiency furnaces.

When it comes time to replace your furnace, be sure to do your research and to compare prices before deciding. You may also consider hiring a contractor to help with the installation process.

Now you know a little more about furnaces. If you are in the market for a new one, be sure to consult with a professional to find the best system for your home. And if you already have a furnace, then Landry Mechanical is your central and metro west Massachusetts go-to for furnace tune-ups, repairs, and replacements. We also offer air conditioning installations and repairs, as well as plumbing or electrical work.

Landry Mechanical
Landry Mechanical

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