How Much Air Conditioning Power Do You Really Need?

(HVAC) system without giving much thought to how well that HVAC system genuinely serves the home. If you take the suitability of your system for granted, you might face years of substandard efficiency, comfort, and expense.

Whether you find yourself installing an HVAC system into a new home or inheriting an existing system in an older home, it pays to think about what degree of air conditioning power you really need. Here are key points to help you in your discussions with an HVAC installer.

Why Right-Sizing Your HVAC System Matters 

One size definitely does not fit all in the world of residential HVAC systems. A large home with a relatively puny air conditioning system may never manage to keep the home sufficiently cool. These efforts will force the system to overwork its various moving parts, leading to premature part failure and frequent repairs.

An underpowered air conditioner forced to run constantly will also use more electricity than a reasonably-sized system that can cycle on and off on a more normal schedule. As a result, you may find yourself paying high utility bills, especially in the summer.

Erring in the opposite direction can also produce problems. An HVAC system too large or powerful for its surroundings will short cycle, turning on and off more frequently than normal. All this extra mechanical activity accelerates wear and tear on components, encouraging expensive breakdowns.

How HVAC Installers Calculate Size/Power Calculations 

HVAC installers can get an approximate notion of your optimal HVAC size and power by multiplying the total square footage of your home by 25. The 25 represents the rough number of British thermal units (BTUs) necessary to cool one square foot. The number obtained from this calculation represents the base BTU requirement.

Vertical space also matters for these calculations, especially if you have a ceiling eight or more feet in height. Installers take a high ceiling into account by multiplying your base BTU figure by 1.25. Using these methods, a 2,000-square-foot home with an eight-foot ceiling needs roughly 46,875 BTUs of cooling power.

How Other Factors Enter Into HVAC Right-Sizing 

Unfortunately, installers must consider many more factors than square footage, base BTU requirements, and ceiling height to get a precise idea of your HVAC needs. Other variables include your home’s building materials, sunlight exposure, and thermal insulation provided by your walls, attic, and windows.

Different climate zones also impose different needs in terms of air conditioner size. Most of Idaho occupies Zone 5. A 1,500-square-foot home like the one in the previous example would most likely require a 2.5-ton air conditioning system.

Without consideration of all these details, even the most skilled and experienced technician would find it all but impossible to right-size an HVAC system for a home or commercial facility accurately. Our HVAC installers make use a standardized industry protocol that addresses all the necessary assessment categories.

While technicians once had to perform these calculations by hand, modern technology allows technicians to enter all the relevant data into a software program. The program then generates finished reports. Even this modern convenience, however, requires careful data entry by experienced HVAC specialists.

For all of these reasons, you can’t afford to rely on guesswork when right-sizing a new HVAC system. Nor can you count on the specifications of an HVAC system installed in an older home, since you have no way of knowing whether the previous homeowner or HVAC installer measured the home’s needs correctly.

Advanced Heating & Cooling can evaluate your home in detail to help ensure that you have the right HVAC system size and power for years of comfort, energy efficiency, and mechanical reliability.

Contact us today to discuss your situation and ask for assistance.


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