The Problems With an Undersized Air Conditioner

By: Brian Schutt  |  July 28, 2015

While not as common as wanting bigger air conditioners, we still receive requests from Indianapolis homeowners for small air conditioners. Not just smaller than what they have, but smaller than what their house needs. And while we understand the driver behind such a request—to lower the price of the new air conditioner being installed—there are two primary problems with installing an undersized air conditioner.

Problem #1: Your Energy Bills Will Rise With Undersized Air Conditioner

While a smaller system does initially cost less than a larger system, the undersized air conditioning unit will lack the necessary capacity to reach the set temperature within an appropriate cycle time.

In other words, your A/C will be running constantly in a futile effort to cool your house. And as you might guess, the perpetually running air conditioner will end up costing more to operate than a right-sized unit that shuts off after effectively reaching the desired temperature. Those desired savings will be nullified by increased operating costs.

Problem #2:  Your Repair Needs Will Increase With Undersized A/C

The undersized air conditioner does not have the power it needs to generate enough velocity to push cool air through the ductwork. Cool air’s coming, but not at the speed it needs in order to affect the comfort inside your home.

And so it keeps working and working and working—the excessive run times mentioned above—putting even more wear and tear on your system. And not surprisingly, your air conditioning unit breaks down more and requires more regular maintenance checks. And when you add those repair costs to the unit cost, the smaller A/C unit ends up costing you more in the end.


Find an HVAC technician that understands the importance of rightsizing your air conditioner to your home. And if you don’t have a go-to HVAC contractor in the Indianapolis area, call us at 317-203-8149.


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