As you are looking for a new furnace, it may be a surprise to see the different sizes various models come in. This provokes a lot of questions. What size do you need to heat your residence effectively? What is a BTU, and how many do you need based on the size of your home? Let’s look at some of these questions and try to determine what size furnace you require.

How Important Is It to Have the Right Size Furnace?

Having the right size furnace is a crucial part of making your home comfortable. A furnace that properly heats the space not only enhances comfort but also helps keep the home’s occupants healthy and safe.

Those who live in a cold climate know that if their home is not adequately heated, the water pipes can freeze, burst and damage their house. Insulation and home heating are the best defenses against this.

You have probably heard the term “BTU” used when discussing air conditioning and heating systems. BTU stands for British thermal unit. This measurement represents how much energy is needed to raise the temperature of one pound of water by one degree Fahrenheit.

Depending on your home’s size and the climate you live in, you will need a furnace that produces a given number of BTUs. You can do some rough calculations to get an estimate. However, the only way to know the size and model of furnace that is right for you is to have a professional from Tarpy Plumbing, Heating & Air inspect your home and show you what size unit may be suitable.

How Important Is the Size of Your Home When Choosing a Furnace?

One of the most significant factors in choosing your furnace will be the square footage of your home. There are many places where you can find this number. If you don’t have access to your blueprints or the documents used when closing on your property, measure each room by its length and width. Multiply the numbers to get the square footage of the room. For example, if you have a room that is 10 feet by 10 feet, you have a 100 square-foot room.

Judging based solely on the size of the home, the following guidelines are a good starting point for deciding the size of the furnace you need:

• 1,200-square-foot house -– 36,000 to 72,000 BTUs
• 1,800-square-foot house -– 54,000 to 108,000 BTUs
• 2,400-square-foot house -– 72,000 to 144,000 BTUs

As you can see, the furnace size recommended for each house is not a set number but a range of numbers. This is why we say that square footage is just one factor to consider.

What Happens If My Furnace Is Too Big for My Home?

Most people think that if they want to keep their home warm, they need to get an oversized furnace. That is not the case. If your furnace is too big, it is going to cause you a ton of problems.

First, your home is going to feel uncomfortable. If the furnace is too big for your space, it will work in quick bursts. The furnace will turn on and make certain parts of your house so hot it is unpleasant. That spike in heat in certain rooms will cause the heater to turn off. Areas where the heat has not yet reached, will feel like a freezer.

Second, an oversized furnace has a reduced lifespan. Because the furnace is working in short bursts, it is constantly cycling on and off. This creates wear and tear on the system and could lead to premature furnace failure. In the lead-up to complete loss, you will need to repair the furnace frequently. This is expensive.

Third, it is not energy efficient. It requires a burst of energy to activate your furnace each time. Having an oversized furnace constantly cycling off and on makes an inefficient system.

What Happens If My Furnace Is Too Small for My Home?

If your furnace is too small for your home, you are also going to feel uncomfortable. This is especially true during the parts of the year when temperatures plummet. Undersized furnaces lack the power to sustain the indoor temperature you want your home to attain.

Your energy bills are going to be high because your furnace will need to run nonstop. This will lead to premature wear and tear, meaning that your furnace will have a shorter lifespan.

As with an oversized furnace, an undersized furnace will create heat spots. There will be parts of your home that could be heated up well by the furnace and other parts that will always be cold.

What Are the Benefits of Having the Right Size Furnace?

Having the right size furnace is beneficial in so many ways. First, it is going to heat your house up gradually.

A gradual heating of your house is energy efficient, and it’s also kind to your furnace. This means your equipment will last a lot longer and need fewer repairs. If you have the right furnace, you won’t be dealing with hot or cold pockets throughout the house.

Get the Right Furnace for Your Climate Zone

You need to get the right furnace for your climate zone. The farther you are from the equator, the more BTUs you will need per square foot of your home. Other factors, such as elevation and ocean currents, may also affect the size of the furnace you will need.

The United States is divided into five climate zones, and San Diego is considered to be in Zone 2, almost the warmest. To put things in perspective, we are located between 32 degrees and 33 degrees north latitude. That’s essentially the same general latitude as places like Italy, Greece, Portugal, and Spain. Consequently, we have what climatologists call a Mediterranean climate. We lie along Southern California’s coast, and our area is dominated by the ocean. Although snow may be common in the mountains to the north and east of San Diego County, it has only ever been seen in this city five times in recorded history. Our record low temperature was only a few degrees below freezing, and that was more than a century ago.

In short, we’re blessed with a mild climate. Still, you will sometimes need your heater. In our part of coastal California, the heating factor is 35 to 40 BTUs per square foot. If you select a model rated for that capacity, it should be sufficient.

Reliable and Dependable HVAC Services

Tarpy Plumbing, Heating & Air is proud to offer heating, cooling, and air quality installation, repair, and maintenance throughout San Diego and the surrounding areas. We also provide a complete line of plumbing services. With years of experience behind us, we can expertly provide the results you need. You can place your confidence in our highly trained technicians and plumbers. To learn more or to schedule an appointment, call us today.

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