Choosing a new air conditioning system or furnace can feel overwhelming. When you're looking 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 equipment provides the most comfort and lowest energy bills, right?
It’s not quite that simple.
Efficiency ratings aren’t the only thing that matters 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 utility bills.
Proper sizing directly impacts humidity control and lasting performance. The best HVAC system for your home delivers energy efficiency and correct sizing.
In this blog, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why proper HVAC system sizing is so important and why qualified HVAC contractors consider both when helping you choose the best HVAC system for your home.
What Does a High SEER Rating Actually Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), shows how effectively an air conditioner cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using test procedures that better simulate real-world operating conditions. Today’s new air conditioners have a SEER2 designation, simply because that is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by something called AFUE, which is short for Annual Fuel Utilization Efficiency. Like SEER and SEER2, 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.
However, high ratings don't by themselves guarantee lower utility bills. Actual heating and air conditioner efficiency depends on many factors, including the quality of the installation, the quality of your ductwork, how much insulation your home has, thermostat settings and, most importantly, system sizing. Even the highest-efficiency system cannot perform as intended if it is too large or smaller than needed for the home.
Why Correct HVAC System Sizing Matters More Than You Probably Think
Many assume a larger air conditioner or furnace will heat or cool a home better or that they should just replace their old HVAC system with a new one the same size. Actually, new heating system installation or AC replacement should be sized based on your home's true heating and cooling needs—not just square footage or the size of the previous unit.
That's why reputable technicians conduct an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation evaluates many variables that affect your home's heating and cooling load, including:
- Overall square footage
- Ceiling height
- Window size and orientation
- Home insultation levels
- Drafts and air leakage
- Local climate
- Household occupants
- Heat produced from appliances and lighting
- Ductwork condition
A properly sized air conditioner runs through longer cooling cycles to cool your home evenly while removing excess humidity. That means steadier temperatures, better indoor comfort and improved humidity control. This also allows the equipment to perform more effciently, reducing strain that can shorten its lifespan or lead to costly breakdowns.
When a furnace or AC is correctly sized, you get greater comfort and long-lasting performance.
Problems with Oversized and Undersized HVAC Equipment
Many homeowners are tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. However, that often isn't a great idea.
HVAC 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.
Drawbacks of Oversized HVAC Systems
An oversized air conditioner or heating system may work quickly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing wear.
- Humidity problems: Oversized air conditioners finish cooling cycles too soon to remove enough moisture from the air.
- Hot and cold spots: Some rooms feel too cool while others stay too warm.
- Additional equipment wear: Even though the system heats or cools your home fast, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Issues Created by Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Continuous operation: The system stays on for extended periods trying to reach the desired temperature, which also causes additional wear.
- Difficulty maintaining the desired temperature: Your home may never feel as cool as you want during hot weather or feel too cool during winter.
- Increased energy consumption: Running nonstop can increase energy costs.
- Added strain during extreme weather: HVAC systems that are too small can struggle in extreme temperatures, increasing equipment wear and the likelihood of repairs.
Finding the Right Balance Between Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, remember that you don't automatically need the highest-efficiency model on the market.
Often, a professionally sized, mid-efficiency heating and cooling system will outperform an oversized premium system because it operates the way it was designed to.
Theideal choice is an energy-efficient HVAC system that's correctly sized for your home, your budget, your climate and your future plans.
When deciding how to choose a new air conditioner or furnace, keep these factors in mind:
- Efficiency savings: Higher-efficiency and right-sized systems can decrease electricity use.
- Upfront investment: High-efficiency AC and heating systems often cost more initially than mid-range models but can lower long-term energy costs.
- Energy prices: Areas with more expensive electricity may see more significant long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's crucial your heating or cooling system has the right capacity to handle areas with extremely cold winters or intense summer heat.
- How long you'll own the home: 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.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can lower 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?
Imagine two neighboring homes.
At the first home, the homeowner chooses a premium high-efficiency HVAC system that's too big because the contractor replaced it with the same size system as the previous unit. The other homeowner installs a correctly sized, mid-efficiency system after completing a Manual J calculation.
While the second system has a lesser efficiency rating on paper, it may provide lower operating costs, better home comfort, improved humidity control and last longer because it's properly matched to the home's needs.
Choose the Local HVAC Professional Who Designs Solutions Tailored to Your Home
An HVAC replacement should involve more than selecting a system with the top efficiency rating. An ideal system is one that meets your home’s heating and cooling requirements.
At Air Commander's Heating & Air Conditioning Co., our knowledgeable technicians perform an HVAC load calculation. Our team will evaluate your home's size and layout, your household's heating and cooling preferences and recommend equipment that's right for your home—not simply the largest, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will help you identify any available rebates and tax incentives and provide information about HVAC financing options that make efficient heating and cooling systems more accessible for all budgets.
Schedule an HVAC consultation online with Air Commander's Heating & Air Conditioning Co. to get started. We'll evaluate your home, answer any questions and help you choose the properly sized energy-efficient system that keeps your family comfortable for many years.
