Choosing a new air conditioning system or furnace can feel overwhelming. If you're trying to find the best HVAC system for your home, it's common to look for models with extremely high efficiency ratings.
After all, the most efficient equipment provides the most comfort and lowest energy bills, right?
Not necessarily.
High efficiency isn't the only thing to think about when it comes to new air conditioner installation or replacing your furnace. While many homeowners 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 system longevity. The best HVAC system for your home delivers energy efficiency and correct sizing.
In thisguide, 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 experienced HVAC professionals consider both when helping you choose 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), indicates how effectively an AC cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using testing methods that better represent real-world operating conditions. Most new air conditioners have a SEER2 designation, simply because this rating is the current rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by AFUE, which is for Annual Fuel Utilization Efficiency. As with SEER and SEER2, 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.
Even so, high ratings don't automatically guarantee lower utility bills. Actual heating and air conditioner efficiency depends on many factors, including the way the system is installed, the state of your ductwork, insulation levels, thermostat settings and, most importantly, system sizing. Even the most efficient system cannot perform as intended if it is too large or undersized for the home.
Why Proper HVAC Sizing Matters More Than Most Homeowners Realize
Many assume a larger air conditioner or furnace will work the best or that they should simply replace their old HVAC system with a same-sized replacement. In reality, new heating system installation or air conditioner replacement should be selected based on your home's current heating and cooling needs—not just square footage or the size of the previous unit.
That's why reputable technicians perform an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation analyzes many factors that affect your home's heating and cooling requirements, including:
- Home square footage
- Ceiling height
- Window size and orientation
- Home insultation levels
- Air infiltration
- Area climate
- Household occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs long enough to cool your home evenly while pulling out excess humidity. That means more even temperatures, better indoor comfort and improved moisture control. This also allows the equipment to run more effciently, reducing unnecessary wear that can reduce its service life or lead to costly breakdowns.
When a furnace or AC is the right size for your home, you get improved comfort and more reliable operation.
Problems with Oversized and Undersized Heating and Cooling Systems
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 too large or smaller than your home requires can create comfort issues, increase energy expenses and reduce efficiency regardless of their SEER rating.
Issues Created by Oversized HVAC Systems
An oversized air conditioner or heating system may heat or cool rapidly, but that doesn't mean it delivers the best comfort.
- Short cycling: An oversized HVAC system starts and stops often, reducing efficiency and increasing wear.
- Reduced humidity control: Oversized air conditioners reach the set temperature too fast to remove enough moisture from the air.
- Inconsistent temperatures: Some rooms get too cold while others stay too warm.
- Increased wear and tear: Even though the system works quickly, those constant cycles can cause avoidable breakdowns due to the strain.
Issues Created by Undersized HVAC Systems
An undersized HVAC system can have the opposite problem:
- Continuous operation: The system runs for long periods trying to reach the desired temperature, which also causes additional wear.
- Trouble reaching the thermostat setting: Your home may not feel comfortable during hot weather or never feel warm enough in cold weather.
- Higher energy use: Running for extended periods can increase utility bills.
- Extra stress during severe weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing equipment wear and the risk of breakdowns.
Balancing Efficiency and Size
When trying to decide between a high SEER vs right-sized system, don't forget that you don't automatically need the most efficient model on the market.
In many cases, a professionally 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 properly sized for your home, your budget, your climate and your long-term goals.
As you think about how to choose a new air conditioner or furnace, think about:
- Lower energy costs: Higher-efficiency and right-sized systems can lower electricity use.
- Purchase price: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can lower long-term energy costs.
- Local utility costs: Areas with higher electricity rates may see greater long-term savings from higher-efficiency units.
- Your local climate: It's crucial 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 higher-efficiency systems.
Real-World Situation: High Seer vs. Right System Size
How does this work 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 simply matched the previous unit. At the neighboring home, an HVAC professional installs a right-sized, mid-SEER or AFUE system after completing a Manual J calculation.
Even though the second system has a more modest efficiency rating on paper, it may deliver lower operating costs, better home comfort, improved humidity control and last longer because it's properly matched to the home's needs.
Choose the HVAC Professional Who Designs Solutions Tailored to Your Home
HVAC replacent or installation should involve more than selecting the unit with the top efficiency rating. The best system is one that meets your household heating and cooling requirements.
At Home Comfort, our knowledgeable technicians perform an HVAC load calculation. We'll evaluate your home's layout and construction, your household's comfort needs 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 HVAC experts will connect you with any available tax rebates 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 Home Comfort today. We'll gladly evaluate your home, answer your questions and help you choose the properly sized high-efficiency system that keeps your family comfortable for many years.