Choosing a new air conditioning system or furnace can be intimidating. If you want to find the best HVAC system for your home, it's common to look for models with extremely high efficiency ratings.
Surely the most efficient system should deliver the most comfort and lowest energy bills, right?
It’s not quite that simple.
Energy efficiency isn't the only thing you should consider when it comes to new air conditioner installation or furnace replacement. Even though many focus only on efficiency ratings, proper HVAC system sizing is often even more important for your home's comfort and your energy bills.
Proper sizing has a major impact on humidity control and system longevity. The best HVAC system for your home delivers efficiency and correct sizing.
In this article, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why correct HVAC size is so important and why qualified HVAC contractors consider both when recommending the best HVAC system for your home.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), measures how efficiently an AC cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using test procedures that better represent real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because that is the current rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by an AFUE rating, which is short for Annual Fuel Utilization Efficiency. As with SEER and SEER2 ratings, higher AFUE ratings indicate a high-efficiency HVAC system that uses less electricity to achieve indoor comfort than lower-rated systems under standardized laboratory testing.
That said, high ratings don't by themselves guarantee lower utility bills. Real-world heating and air conditioner efficiency depends on many factors, including the installation quality, the quality of your ductwork, your home's insulation, thermostat settings and, most importantly, proper HVAC system sizing. Even the most efficient system cannot perform as intended if it is bigger than necessary or too small for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a higher-capacity air conditioner or furnace will work the best or that they should simply replace their old HVAC system with a new one the same size. In reality, new heating system installation or a new air conditioner should be selected based on your home's actual heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable technicians complete an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation analyzes many variables that impact your home's comfort needs, including:
- Home square footage
- Ceiling height
- Window size and placement
- Insulation
- Drafts and air leakage
- Regional climate
- Number of occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs through longer cooling cycles to cool your home consistently while removing excess humidity. That means more even temperatures, better indoor comfort and improved indoor humidity management. This also allows the equipment to perform more effciently, reducing unnecessary wear that can reduce its service life or lead to frequent or expensive repairs.
When your heating or cooling system is properly sized, you get greater comfort and more dependable performance.
Problems with Oversized and Undersized Systems
It might be tempting to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. The truth is, that’s rarely a great idea.
heating and cooling systems that are bigger than your home needs or smaller than your home requires can create comfort issues, increase energy expenses and reduce efficiency regardless of their SEER rating.
Common Problems With Oversized HVAC Systems
An oversized air conditioner or heating system may heat or cool rapidly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system starts and stops often, reducing efficiency and increasing equipment strain.
- High indoor humidity: Oversized air conditioners cool your home too quickly to remove excess moisture from the air.
- Hot and cold spots: Some rooms become too cold while others never feel comfortable.
- Increased wear and tear: Even though the system works quickly, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Cons Associated with Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Long run times: The system stays on for extended periods trying to reach the desired temperature, which also causes extra strain.
- Difficulty maintaining the desired temperature: Your home may not feel comfortable during hot weather or feel too cool during winter.
- Greater energy usage: Running nonstop can increase energy costs.
- Added strain during extreme weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing equipment wear and the chance of failure.
Balancing Efficiency and Size
When trying to decide between a high SEER vs right-sized system, keep in mind that you don't automatically need the highest-efficiency model on the market.
In many cases, a correctly sized, mid-efficiency heating and cooling system will outperform an oversized premium system because it functions the way it was designed to.
Thesmartest choice is an energy-efficient HVAC system that's matched for your home, your budget, your climate and your long-term goals.
As you consider how to choose a new air conditioner or furnace, consider:
- Energy savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Initial cost: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can reduce long-term energy costs.
- Energy prices: Areas with more expensive electricity may see more significant long-term savings from higher-efficiency units.
- Climate: It's important your heating or cooling system has the right capacity to handle areas with extremely cold winters or very hot summers.
- Time you plan to own the home: If you intend to remain in your home for many years, the long-term energy savings of a higher-efficiency unit may be worth the investment.
- Financial incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can lower the overall cost of qualifying equipment.
Real-World Example: High Seer vs. Right System Size
How does this work in the real world?
Suppose there are two neighboring homes.
At the first home, the homeowner chooses a premium high-efficiency HVAC system that's too big for the house because the contractor replaced it with the same size system as the previous unit. The other homeowner installs a properly sized, moderate-efficiency system after completing a Manual J calculation.
While the second system has a more modest efficiency rating on paper, it may provide lower operating costs, better home comfort, improved humidity control and have a longer lifespan because it's properly matched to the home's needs.
Choose the HVAC Professional Who Designs Personalized Solutions
An HVAC replacement should involve much more than selecting a model with the top efficiency rating. The best system is one that meets your home’s heating and cooling requirements.
At B&B Heating, Cooling, Plumbing & Electrical, our knowledgeable technicians perform an HVAC load calculation. We'll carefully evaluate your home's design, your household's comfort goals and recommend equipment that's properly matched for your home—not simply the highest-capacity, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will connect you with any available tax rebates and provide information about HVAC financing options that make high-efficiency systems more accessible for all budgets.
Schedule an HVAC consultation online with B&B Heating, Cooling, Plumbing & Electrical now. We'll evaluate your home, answer any questions and help you choose the properly sized efficient system that keeps your family comfortable for years to come.