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What’s This “Tonnage” Mean for a New Furnace?

When the time arrives for a new installation of a furnace in Brighton, MI for your house, you’ll have to navigate plenty of numbers and stats aside from the price of the unit. For example, there’s the AFUE rating, which is how the energy efficiency of a furnace is rated. The higher the percentage, the more efficiently it uses fuel.

One number you’ll hear often is the tonnage of the new system. It’s vital that your furnace has the proper tonnage for your home. What does this actually mean, and how do you find the right tonnage?

Tonnage Is Heating Power

Tonnage doesn’t have anything to do with how much a furnace weighs. Tonnage is actually a useful measure of the amount of heat the furnace can put out. To explain more, we’ll have to go into some numbers …

The smaller unit of heat measure used in HVAC installation is the BTU, or British Thermal Unit. One BTU is the amount of heat necessary to change a pound of water by one degree—adding heat to warm it or removing heat to cool it. (This is why you’ll hear BTUs used with air conditioners as well; it’s the amount of heat the system removes from the air.)

Since BTUs are such as small amount, tons are used for greater convenience. One ton is equal to 12,000 BTUs. Why is it called a ton? Because it’s the amount of heat necessary to melt one ton of ice.

The Tonnage of Your Future System

Now that you know what tonnage means, how many tons of heating is “a lot” and how much is “too little”?

Tonnage varies widely. For example, commercial HVAC systems are often in excess of 50 or even 100 tons of power. Under 25 tons is consider a “light commercial” system. For single-family homes, such as the one you’re probably looking to heat, most furnaces will be between 1 to 5 tons.

This isn’t something you want to guess. Matching the tonnage of a furnace or any other HVAC system to a house must be precise—no “guesstimates”! It’s not a simple process to find the proper tonnage (“sizing” a unit) for a home. A larger home will need more tonnage of heat than a small home, but square footage alone won’t provide a proper answer.

This is where hiring HAVC professionals for a furnace installation is essential. Part of the installation is performing a heat load calculation for the house. This calculation takes information about the home and combines it to come up with how many tons of heat are required for comfort without turning wasteful. A heater with too much tonnage is just as bad as one with too little. The installers consider factors such as the home’s square footage, the volume of rooms, the amount of people who live there, heat from lights, heat coming through windows, and insulation. When they’re done, they’ll know the exact tonnage for your new furnace.

Schedule an appointment with First Choice Heating & Cooling when you need furnace installation. If your home had a voice, it would call First Choice!

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