Why phone sizing does not work
Proper system sizing matters for both your comfort and your operating costs. A unit that is too small struggles to keep up on hot days. A unit that is too large short cycles, which wastes energy and removes less humidity. To land on the right tonnage, an accurate sizing needs many details about your specific home, and those details cannot be gathered in a quick phone call.
What actually affects AC sizing
Square footage is only the starting point. A full sizing review, often called a Manual J load calculation, weighs several other factors before settling on a capacity. Skipping these factors is the most common reason a system ends up the wrong size.
| Factor | Why it matters |
|---|---|
| Number and type of windows | Glass adds heat gain, especially on sun facing walls. |
| Attic and wall insulation | Better insulation lowers the cooling load. |
| Your climate | Hot, humid regions demand more capacity than mild ones. |
| Occupants and lifestyle | More people and heat producing activity raise the load. |
How AC Direct helps you size a system
Because a reliable answer cannot come from a phone call, we offer a number of options to make sure your new system is sized for maximum comfort and efficiency. Our sizing resources walk you through the same factors a load calculation uses, so you can match the equipment to your home before you order. AC Direct sells the equipment online and ships it direct, and the AC Direct Price Promise keeps your pricing competitive while you get the size right.
Take your time with the numbers
It is worth gathering your home details before you shop. Once you have your square footage, window count, insulation levels, and climate in hand, choosing the correct tonnage becomes straightforward and you avoid the cost of an oversized or undersized unit.
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25 years sizing and shipping HVAC systems to homeowners and contractors.
