Shopping for a new AC or furnace can be stressful. If you're trying to find the best HVAC system for your home, it's understandable to focus on models with extremely high efficiency ratings.
Surely the most efficient system provides 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 {energy efficiency|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 long-term reliability. The best HVAC system for your home combines energy efficiency and correct sizing.
In thisarticle, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why proper HVAC system size is so important and why trusted HVAC experts consider both when recommending the best HVAC system for your home.
What Does it Mean if an AC Has a High SEER Rating?
A SEER rating, (Seasonal Energy Efficiency Ratio), measures how efficiently an air conditioner cools your home over a standard cooling season. A SEER2 rating is the newer version of SEER, using evaluation methods that better reflect real-world operating conditions. Today’s new air conditioners have a SEER2 efficiency rating, simply because this rating is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by an AFUE rating, which stands for Annual Fuel Utilization Efficiency. Similar to cooling efficiency 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.
Even so, high numbers don't automatically guarantee lower utility bills. Real-world heating and air conditioner efficiency depends on several key factors, including the quality of the installation, the condition of your ductwork, your home's insulation, thermostat settings and, most importantly, system sizing. Even the highest-efficiency system cannot perform as intended if it is bigger than necessary or undersized for the home.
Why Correct HVAC System Sizing Matters More Than You Think
Many assume a larger air conditioner or furnace will heat or cool a home better 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 true heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable contractors complete an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation evaluates many variables that impact your home's comfort needs, including:
- Overall square footage
- Room height
- Window size and direction
- Insulation
- Drafts and air leakage
- Area climate
- Number of occupants
- Heat produced from appliances and lighting
- Air duct condition
A properly sized air conditioner runs for enough time to cool your home consistently while removing excess humidity. That means more even temperatures, better indoor comfort and improved humidity control. Proper sizing also helps the equipment to operate more effciently, reducing strain that can reduce its service life or lead to more repairs and higher repair costs.
When a furnace or AC is correctly sized, you get improved comfort and long-lasting performance.
Problems Caused by Oversized and Undersized Heating and Cooling Systems
It might be tempting to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. However, that often isn't a great idea.
HVAC systems that are too large or too small can create comfort problems, increase energy expenses and reduce efficiency regardless of their SEER rating.
Drawbacks of Oversized HVAC Systems
An oversized air conditioner or heating system may work quickly, but that doesn't mean it performs efficiently.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing equipment strain.
- Reduced humidity control: Oversized air conditioners reach the set temperature too fast to remove enough moisture from the air.
- Uneven temperatures: Some rooms become too cold while others never feel comfortable.
- Additional equipment wear: Even though the system reaches the target temperature rapidly, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Continuous operation: The system stays on for extended periods trying to reach the set temperature, which also causes additional wear.
- Trouble reaching the thermostat setting: Your home may never feel as cool as you want during hot weather or never feel warm enough in cold weather.
- Greater energy usage: Running almost constantly can increase utility bills.
- Added strain during extreme weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing component strain and the chance of failure.
Balancing Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, keep in mind that you don't automatically need the most efficient model on the market.
More often than not, a professionally sized, mid-efficiency HVAC system will outperform an overly large premium system because it runs the way it was designed to.
Theideal choice is an energy-efficient HVAC system that's matched for your home, your budget, your climate and your long-term goals.
When deciding how to choose a new air conditioner or furnace, consider:
- Efficiency savings: Higher-efficiency and right-sized systems can lower electricity use.
- Upfront investment: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can reduce long-term energy costs.
- Electricity rates: Areas with higher electricity rates may see greater long-term savings from higher-efficiency units.
- Climate: It's crucial your heating or cooling system has adequate capacity to handle areas with harsh winter weather or extremely hot summers.
- Length of home ownership: If you plan to stay in your home for many years, the long-term energy savings of a higher-efficiency unit may offset the investment.
- Available rebates or tax incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can reduce the overall cost of qualifying equipment.
Real-World Situation: High Seer vs. Right System Size
How does this play out in a real world scenario?
Suppose there are two neighboring homes.
In the first, the homeowner chooses a premium high-efficiency HVAC system has far more capacity than the home needs because the contractor replaced it with the same size system as the previous unit. At the neighboring home, an HVAC professional installs a correctly sized, mid-SEER or AFUE system after completing a Manual J calculation.
While the second system has a lower efficiency rating on paper, it may provide lower operating costs, better home comfort, improved humidity control and last longer because it's correctly matched to the home's needs.
Work With an HVAC Professional Who Designs Solutions Tailored to Your Home
Replacing your HVAC system should involve much more than selecting a model with the highest efficiency rating. The right system is one that meets your home’s heating and cooling requirements.
At Woody's Sudden Service, our experienced professionals perform an HVAC load calculation. We'll evaluate your home's size and layout, your household's heating and cooling preferences and recommend equipment that's properly matched for your home—not simply the biggest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will connect you with any available rebates or tax incentives and provide information about HVAC financing options that make high-efficiency systems more accessible for all budgets.
Schedule an HVAC consultation online with Woody's Sudden Service today. We'll gladly evaluate your home, answer your questions and help you choose the properly sized efficient system that keeps your family comfortable for the long haul.
