Choosing a new air conditioner or furnace can be intimidating. If you want to find the best HVAC system for your home, it's understandable to focus on models with the highest efficiency ratings.
After all, the most efficient system will provide the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
Energy efficiency isn'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 just as, if not more important for your home's comfort and your utility bills.
Proper sizing has a major impact on humidity control and lasting performance. The best HVAC system for your home combines 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 trusted HVAC experts consider both when recommending the best HVAC system for your home.
What Does a High SEER Rating Actually Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), measures how effectively a cooling system cools your home over a typical cooling season. A SEER2 rating is the updated version of SEER, using test procedures 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 measured 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 heat your home than lower-rated systems under standardized laboratory testing.
However, high ratings don't automatically guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on more than just efficiency ratings, including the quality of the installation, the condition of your ductwork, your home's insulation, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot deliver peak performance 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 bigger air conditioner or furnace will make their home the most comfortable or that they should just replace their old HVAC system with a unit of the same capacity. In reality, new heating system installation or a new air conditioner 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 recommending replacement equipment. A Manual J calculation considers many details that impact your home's heating and cooling requirements, including:
- Total square footage
- Room height
- Window size and placement
- Insulation
- Air leakage
- Local climate
- Household occupants
- Heat produced from appliances and lighting
- Ductwork condition
A properly sized air conditioner runs long enough to cool your home consistently while eliminating excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to perform more effciently, reducing unnecessary wear that can shorten its lifespan or lead to more repairs and higher repair costs.
When your heating or cooling system is the right size for your home, you get better comfort and more reliable operation.
Problems with Oversized and Undersized Heating and Cooling Systems
You may be tempted to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. In reality, that’s rarely a smart choice.
heating and cooling systems that are too large or undersized can create comfort problems, increase utility costs 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 starts and stops often, reducing efficiency and increasing equipment strain.
- Humidity problems: 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.
- Increased wear and tear: Even though the system heats or cools your home fast, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Cons Associated with Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Long run times: The system runs for long periods trying to reach the desired temperature, which also causes extra strain.
- Difficulty reaching thermostat settings: Your home may never feel as cool as you want during hot weather or never feel warm enough in cold weather.
- Higher energy use: Running for extended periods can increase monthly energy expenses.
- Added strain during extreme weather: HVAC systems that are too small can work harder in extreme temperatures, increasing equipment wear and the likelihood of repairs.
Balancing Efficiency and Size
When trying to decide between a high SEER vs right-sized system, remember that you don't always need the most efficient model on the market.
In many cases, a correctly sized, mid-efficiency heating and cooling system will provide better results than an overly large premium system because it functions 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 future plans.
As you consider 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 have a higher purchase price than mid-range models but can help reduce long-term energy costs.
- Electricity rates: Areas with more expensive electricity may see better long-term savings from higher-efficiency units.
- Climate: It's important your heating or cooling system has the right capacity to handle areas with very cold winters or intense summer heat.
- How long you'll 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 offset the investment.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can reduce the overall cost of higher-efficiency systems.
Real-World Comparison: High Seer vs. Right System Size
How does this work in a real world example?
Picture two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system that's too big because the contractor simply matched the previous unit. Next door, the second homeowner installs a correctly sized, moderate-efficiency system after completing a Manual J calculation.
While the second system has a lower efficiency rating on paper, it may deliver lower operating costs, better home comfort, improved humidity control and have a longer lifespan because it's appropriately sized to the home's needs.
Choose the Local HVAC Professional Who Designs Solutions Tailored to Your Home
HVAC replacent or installation should involve much more than selecting a model with the top efficiency rating. The right system is one that meets your heating and cooling requirements.
At Botts & Tye Air Conditioning and Heating, our knowledgeable technicians perform an HVAC load calculation. We'll evaluate your home's size and layout, your household's comfort needs 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 heating and cooling specialists will let you know about 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 Botts & Tye Air Conditioning and Heating to get started. We'll gladly evaluate your home, answer your questions and help you choose the right-sized efficient system that keeps your family comfortable for years to come.