Single vs. Two-Stage Furnaces: What Are They and Which Is Better? 

The purpose of a furnace is to heat your home. During the cold season, you may need to install a furnace so that you can keep your home in reasonable temperatures. The most common furnaces are the single-stage and two-stage (double-stage) furnaces. Each of these furnaces has its advantages, although there is a chance that one may outdo the other in certain circumstances. As you plan to install a furnace in your home, it is essential to understand each furnace and its function.

Single Stage Furnace

Single-stage furnaces are made of a furnace body, fresh air enter pipe and exhaust pipe. A fan or blower is installed to blow the warm air into your home. In addition to heating your home, a single-stage furnace also provides air circulation in the room.

The purpose of this furnace is to provide heat and ventilation simultaneously. The fan will be operative during hours when you need heat, and it will shut down when you don’t need as much heat as it provides. Single-stage furnaces use less heat than double-stage furnaces. Its lower operating temperature allows it to operate at lower efficiency levels—the difference in efficiency results from the single-stage furnace’s lower operating temperature.

What Are the Benefits of the Single Stage Furnace?

  • Less expensive to buy and operate than a two-stage furnace.
  • They are designed to operate at lower efficiency levels.
  • Low maintenance free.

Compared to the two-stage furnace, the single-stage furnace is lighter and does not require much space in your home. Compared to the two-stage furnace, the single-stage furnace has fewer moving parts that can wear out more quickly and cause more maintenance problems.

What Are the Disadvantages of Using Single-Stage Furnaces?

  • At times, this furnace may not be able to heat your home at the right time of the day.
  • During the cold seasons, the single-stage furnace will use more energy and cost more to run than the two-stage furnace s.
  • Due to lower efficiency levels and less airflow, the single-stage furnace can cause higher heating bills in your home.
  • A single-stage furnace may produce loud noises when operating.
  • The fan of this furnace will not shut off once it has started blowing warm air into your home.
  • Low-efficiency levels cause the entire furnace to cool down more than you might need.

Two-Stage Furnace

The two-stage furnace comprises a furnace body, the heat exchanger, the fresher air intake, and the exhaust pipe. The heat exchanger consists of an internal coil that receives heat from your heater room and transfers it to your coils. The air leaving the heat exchanger will pass through an external coil that directs it back into your home.

Two-stage furnaces provide for heating, recovery, and ventilation into your home. Since this type of furnace can supply more heat than your home can absorb because of its lower operating temperature, you may have to replace the air cleaner periodically. A two-stage furnace is more efficient than a single stage and will use less energy.

What Are the Advantages of Using a Two-Stage Furnace?

  • The two-stage furnace can heat your home on a 24/7 basis without requiring any outside help.
  • The two-stage furnace is more effective than a single-stage heating your home, providing warmer temperatures.
  • A two-stage furnace does not require as much space in your home as the single-stage furnace does and will be lighter in weight.
  • Compared to a single-stage furnace, the two-stage can circulate more air in your home and improve its ventilation system using the air intake and exhaust pipes located directly outside your home.
  • The two-stage furnace is safer since it does not have a single-stage furnace s’ small fans. The fans of most two-stage furnaces are built into the heat exchanger so that the heat exchanger can be used to blow warm air into your home even when it is not providing heat.

A two-stage furnace will be more economical to operate than a single-stage because it will consume less electricity while maintaining higher temperatures within your home. The two-stage furnace is quieter than a single-stage furnace.

What Are the Disadvantages of Using a Two-Stage Furnace?

  • A two-stage furnace can produce more noise than a single-stage furnace would.
  • If the two-stage furnace has a problem with its timer, you may have to reset it after turning it off and on again.
  • If the two-stage furnace overheats, it might shut down unexpectedly. If your home happens to be cold, this can cause severe problems since you will not heat it properly.
  • When turning on a two-stage furnace for the first time, there may be an odour coming from exhaust pipes caused by different gases mixing. It is entirely normal and should disappear quickly once the system begins running.
  • The two-stage furnaces do not have the “Self Diagnostic” feature that comes with a single-stage furnace.
  • A two-stage furnace will overheat more often than a single-stage furnace due to the high operating temperature and not having as much ventilation in your home.

Which of the Two Furnaces Is the Best for Your Home?

There are certain circumstances where you should opt for the single-stage furnace, and there are certain circumstances where you should opt for the double-stage furnaces. For example, if your home has a smaller heater room or if space is an issue–then you may want to go for the Single Stage Furnace.

On the other hand, if your space allows for more efficiency when it comes to heating–then you may want to go for the Double Stage Furnace. Many factors such as convenience, capacity, room size and efficiency will determine which type of furnace you should install in your home.

The first step you should take in deciding which would work best is to run the numbers, precisely the amount of money you are spending on heating costs each month. That will tell you which one will be suitable for your home. You can find out what kind of furnace you have by looking at the nameplate on top of your unit and its control board. You can also check online by following the steps below.

Also, before you decide which is suitable for your home, you may need to compare the cost per square foot of heating over a year, and you can get help from any air conditioning company in your area. After you have the percentage per square foot that your heating costs are costing you, you can compare the numbers and pick the most affordable.

Also, there are different options available depending on the type of home you live in, what size it is, and how many people want to stay warm in it during winter. In some cases, a two-stage furnace may be more cost-effective than a single-stage furnace because of its lower operating temperature. Also, it sits at a higher temperature than a single-stage furnace to heat air better and more evenly within a room.


Welcome to our website, the ultimate hub for the latest information! Discover the latest trends, innovations, and advancements in the world of technology, business and health. Explore our collection of informative articles, insightful guides , and helpful tips to enhance your savviness.

Learn More →

Leave a Reply