Many home or business owners don’t realize how important ºÚÁÏ³Ô¹Ï size is to heating and cooling processes, and those that realize size matters often think it’s as simple as getting a bigger unit for a bigger space. In reality, matching an ºÚÁÏ³Ô¹Ï unit to any space requires a complex formula.
Why Consider ºÚÁÏ³Ô¹Ï Size?
Most residential ºÚÁÏ³Ô¹Ï systems could benefit from resizing, says the US Department of Energy. ºÚÁÏ³Ô¹Ï systems that are undersized, or not powerful enough for the given space, run at full capacity much of the time without providing optimal comfort levels in the home or business. Oversized systems may short cycle, which is inefficient. Either way, home or business owners are losing money via utility costs and are more likely to experience additional ºÚÁÏ³Ô¹Ï repair needs when compared to a building equipped with the right system.
How Professionals Choose ºÚÁÏ³Ô¹Ï Systems
The American Society of Heating, Refrigerating, and Air-Conditioning Engineers cautions against simple rule-of-thumb approaches to ºÚÁÏ³Ô¹Ï sizing. Every building is unique: Construction materials, duct design, and interior space shape and size are all taken into account when professionals recommend an ºÚÁÏ³Ô¹Ï system.
According to the US DOE strategy guide for energy efficiency and renewable energy, during new construction, a best practice is to select an ºÚÁÏ³Ô¹Ï system according to size and construction, and then design duct work to match the system. In many cases, new ºÚÁÏ³Ô¹Ï systems are being installed in homes or businesses where duct work already exists, making it a more complex process to select a correct system.
The DOE and ASHRAE recommend using Manual J load calculations, along with other information, to determine the right ºÚÁÏ³Ô¹Ï unit for any space. Manual J loads consider three factors: heating load, sensible cooling load, and latent cooling load. Professional ºÚÁÏ³Ô¹Ï installers also consider outdoor temperatures for a location, average indoor temperatures for a space, and airflow estimates in cubic feet per minute.
Because heating and cooling loads are very different, the bulk of the decision process in the lower 48 states is based on cooling loads. Cooling generally requires more blowing power, so the DOE recommends that heating load capacity not exceed 140 percent; although excess heating capacity may diminish efficiencies slightly in colder months, it helps meet cooling needs for better warm-month ºÚÁÏ³Ô¹Ï performance.
Getting a Professional Opinion
Selecting an ºÚÁÏ³Ô¹Ï system can involve complex calculations, and many existing ºÚÁÏ³Ô¹Ï units are sized wrong for the space they heat and cool. Changes to the home, including remodeling, adding insulation, or installing new windows, could change your ºÚÁÏ³Ô¹Ï needs. Whether installing a new unit or replacing an old one, getting professional advice about your current needs ensures your new system is as efficient and cost-effective as possible.
With licensed, trained, and insured technicians in Westchester and Fairfield, homeowners can count on A. Borrelli ºÚÁÏ³Ô¹Ï to handle their heating, cooling, and plumbing needs expediently. At A. Borrelli, we do ºÚÁÏ³Ô¹Ï and plumbing right, so call us at (914) 301-7495 today!
Sources: http://www.lowesforpros.com/Construction-and-Contractors/Find-the-Correct-Size-of-ºÚÁϳԹÏ-Systems, http://apps1.eere.energy.gov/buildings/publications/pdfs/building_america/strategy_guide_hvac_sizing.pdf
