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Althoff Industries, Inc. Blog

The Importance of Professional Sizing for Commercial AC Installations


When it comes to the installation of commercial air conditioning for your facility, you don’t want anyone but the best professionals to handle the job. Our team has decades of experience installing air conditioning systems for a wide range of companies and buildings, and we never take shortcuts—we know there are no shortcuts when it comes to quality work. 

One of the most important steps for proper commercial air conditioning installation is sizing the new unit. We’ll explain what this process is and why ensuring it’s done correctly is critical for a commercial HVAC system to operate effectively and efficiently.

Sizing Refers to the Cooling Capacity of an AC

When commercial HVAC technicians talk about sizing an air conditioner, they aren’t talking about how physically large the unit is. Size is the cooling capacity of the unit, and how much cooling power it can supply by removing heat from the air and sending the cooled air into the building’s ventilation system. 

The capacity of an air conditioning system is measured in units called tons. Again, this has no connection to how much the AC unit weighs. One ton of cooling capacity is equal to 12,000 BTUs of heat removed per hour. The reason this amount of heat removed is referred to as a ton is because it’s the amount of heat necessary to melt one ton of ice over 24 hours.

Residential homes have air conditioning systems from 5 to 10 tons. Up to 25 tons is considered light commercial, and anything over that is heavy commercial or industrial. Facilities may require several hundred tons of cooling capacity, which installers can supply with multiple modular AC units. So sizing isn’t just finding the right size of individual air conditioner, it can be finding the number of air conditioning units necessary to meet the tonnage requirement of the space.

What Happens When Sizing Is Done Incorrectly

You can probably grasp why an undersized commercial AC system is a serious problem. If the cooling capacity of the system cannot match the demand of the facility, not only will the facility be too warm, but the air conditioner will run almost continuously trying to meet demands it cannot meet.

But what’s wrong with a system that’s too big? Isn’t it better to err on the side of too much? Not in this case! An oversized commercial air conditioning system will run into the problem of short-cycling: it will lower the indoor temperature so rapidly that the thermostats will incorrectly register that the AC is finished and shut it off early. The AC will come right back on and repeat the process. This puts a huge strain on the air conditioner and rapidly runs up bills. The air conditioning system will likely fail years too early because of the excess stress from short cycling.

Leave Your Commercial AC Needs to Us

Our service for commercial air conditioning in Northbrook, IL will see that you get the correct size and type of air conditioning system for your facility, no matter what type it is. 

Contact Althoff Industries, Inc. today. Challenges Accepted!

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