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Load Calculation & the Importance of Proper AC Unit Sizing

It is no secret that older HVAC systems are more unreliable and less efficient than modern units. If it’s time to replace your aging HVAC unit with a high-efficiency model, it is important to purchase the correct size to ensure appropriate cooling/heating output and optimal energy savings. According to the Department of Energy, national surveys indicate that over 50% of contractors may be sizing HVAC units incorrectly! Blanton’s Heating and Air service professionals are skilled and detail focused, spending a great deal of time measuring your home and assessing the comfort requirements of your space.

What You Can Expect During Your System Sizing Consultation

To properly size your heating and AC equipment, we spend an average of three hours visiting your home. We use Manual J load calculation methods established by the industry-leading Air Conditioning Contractors of America, and these precision calculations are based upon a combination of:

Room-by-room load calculations: These calculations factor in room size, ceiling height, window size and window type (single/double-pane, etc.) for every room in your home.

Home structure: The size and type of AC unit is partially based upon your home’s construction. This includes siding type (brick, vinyl, etc.), as well as insulation R-values in walls and attic.

Ductwork assessments: To assess your ductwork, we take photos and consider the overall design as well as cosmetic damage, loose pieces, and other construction concerns.

Structural orientation: It is important to note the direction that your home faces and how much sunlight you get during peak hours. Many companies overlook this critical part of HVAC sizing.

Existing unit specifics: During your new system consultation, we review each facet of your existing equipment to determine how a new unit can cost effectively improve comfort and reduce energy use.

Comfort preferences: Blanton’s does not believe in one-size-fits-all solutions. Instead, we hand-select and properly install a system that meets your needs and temperature requirements without busting your utility budget.

Why does Blanton’s spend so much time on HVAC sizing?For several reasons:

  • To ensure accuracy. The more accurate our information is, the more accurate our installation recommendations will be—and this preserves your safety, comfort and satisfaction.
  • To achieve proper humidity control. When humidity is managed by a correctly sized system, you may be just as comfortable at 78 degrees as you previously were at 76 degrees—which saves you money. A system that is too large may short-cycle, causing humidity buildup and reducing comfort.
  • To lengthen equipment lifespan. According to the U.S. Department of Energy, “Similar to an automobile in stop-and-go traffic, the overall efficiency of an air conditioner, furnace, or heat pump is reduced by excessive cycling. More starts and stops accelerate wear and tear on the equipment, which can lead to premature failure.”

When a heating and cooling system is too small, it won’t get the job done—and will continually run without a break. As a result, comfort suffers and energy bills can soar. You may have already experienced this if you own an aging or inefficient system.

When a heating and cooling system is too large, it increases your initial investment while reducing efficiency. One Florida study even indicated a 9 percent average increase in annual electricity usage for units that were oversized.

Trust Blanton’s to Size Your New HVAC System

Do not trust a “casual” sizing estimate for your new heating and cooling system. Not every company uses ACCA-approved methods for sizing HVAC equipment. As a result, you may end up with a more expensive system than you need—or a system that is too small to get the job done. And remember, proper installation is critical to HVAC performance. Even the best AC or heating system will not perform to specifications if it is improperly installed!

At Blanton’s Heating & Air, our NATE-certified service professionals take the time to thoroughly assess your comfort requirements and home design so your new system will provide optimal climate control at affordable prices. Call (910) 822-2866 to schedule a new system consultation, or contact us online today!

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