How to Estimate the Right Furnace Size

Choosing the right size of furnace for your home can be tricky, which is why Tyler Heating, Air Conditioning, Refrigeration LLC, the best HVAC company in the state, shares how professional contractors estimate the right size below.

Does It Have to Be the Exact Size?

Some might be wondering if the size of a furnace replacement really matters. After all, wouldn’t a bigger furnace be able to heat your home faster? Well, not necessarily.

The biggest problem with oversized furnaces is their lack of efficiency. Bigger furnaces, due to their larger heating capacities, tend to release heat in small bursts, making it uncomfortably hot inside your home. This spike in indoor temperatures will then prompt the heater to shut down, causing temperatures inside to drop sharply. The resulting on-and-off cycling will not only make indoor temperatures uncomfortable, it will also raise your energy consumption.

How to Estimate the Right Size

The size of a furnace replacement gives you an idea of its heating capacity, which is expressed in British thermal units (BTU). Naturally, the bigger your house, the more BTUs your furnace needs to produce. To find the right size, you’ll need to:

Calculate the total area of the room – For irregularly-shaped rooms, you can divide the space into smaller sections and find the area of each section individually.

Find out which climate zone your area falls under. There are five zones in the US:

• Zone 1 – The country’s southernmost regions are located in this zone. The recommended heating factor is 30 to 35 BTUs.

• Zone 2 – Coastal California and the southern cities of Atlanta and Little Rock are part of this zone, which has a heating factor of 35 to 40 BTUs.

• Zone 3 – Virginia as well as the states to the west of it fall into this zone. The recommended heating factor is 40 to 45 BTUs.

• Zone 4 – Boston, New York and Chicago are part of this climate zone, which has a heating factor of 45 to 50 BTUs.

• Zone 5 – The northernmost states have the highest heating factor at 50 to 60 BTUs.

Multiply the total square footage of your house by your climate zone’s recommended heating factor to find out the number of BTUs needed to maintain a warm, comfortable home. Just keep in mind that this rough estimate will be in the lower range.

What Are the Other Factors?

However, other factors can affect the recommended number of BTUs as well, such as the number of people living inside your home, its current condition and its exposure to the sun. The only way to get an exact number is to consult a professional HVAC contractor.

Tyler Heating, Air Conditioning, Refrigeration LLC, the winner of the Carrier® President’s Award for three years in a row, offers a wide range of professional HVAC services, including heat pump repair services. To get a free estimate on your new furnace, call us at (203) 378-4700 or leave us a message here.