Shopping for 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 the highest efficiency ratings.
After all, the most efficient heating and cooling system provides the most comfort and lowest energy bills, right?
Not necessarily.
Efficiency ratings aren’t the only thing you should consider when it comes to new air conditioner installation or installing a new furnace. Even though many focus only on efficiency ratings, proper HVAC system sizing is equally, if not more important for your home's comfort and your power bills.
Proper sizing directly impacts humidity control and long-term reliability. The best HVAC system for your home combines energy efficiency and correct sizing.
In this article, 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 select 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 air conditioner cools your home over a standard cooling season. A SEER2 rating is the current version of SEER, using testing methods that better simulate real-world operating conditions. Today’s new air conditioners have a SEER2 rating, simply because this is the current rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by an AFUE rating, which is for Annual Fuel Utilization Efficiency. Like cooling efficiency ratings, higher AFUE ratings indicate a high-efficiency HVAC system that uses less electricity to keep you comfortable than lower-rated systems under standardized laboratory testing.
However, high ratings don't automatically guarantee lower utility bills. Real-world heating and air conditioner efficiency depends on many factors, including the quality of the installation, the state of your ductwork, insulation levels, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot deliver peak performance if it is too large or undersized for the home.
Why HVAC System Size Matters More Than You Probably Think
Many assume a higher-capacity air conditioner or furnace will work the best or that they should just replace their old HVAC system with a new one the same size. Actually, 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 the previous unit.
That's why reputable technicians complete an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation evaluates many factors that impact your home's heating and cooling load, including:
- Total square footage
- Ceiling height
- Window size and orientation
- Home insultation levels
- Air infiltration
- Local climate
- Number of occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home more uniformly while removing excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. It also helps the equipment to perform more effciently, reducing unnecessary wear that can reduce its service life or lead to costly breakdowns.
When HVAC equipment is the right size for your home, you get greater 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. The truth is, that's usually not a great idea.
heating and cooling 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 heat or cool rapidly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing equipment strain.
- Humidity problems: Oversized air conditioners finish cooling cycles too soon to remove excess moisture from the air.
- Uneven temperatures: Some rooms feel too cool while others never feel comfortable.
- Increased wear and tear: Even though the system reaches the target temperature rapidly, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Long run times: The system runs for long periods trying to reach the desired temperature, which also causes unnecessary wear and tear.
- Trouble reaching the thermostat setting: 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 utility bills.
- Extra stress during severe weather: HVAC systems that are too small can work harder in extreme temperatures, increasing wear and the chance of failure.
Finding the Right Balance Between Efficiency and Size
When trying to decide between a high SEER vs right-sized system, remember that you don't necessarily need the top-efficiency model on the market.
Often, a correctly sized, mid-efficiency HVAC system will deliver better performance than an overly large premium system because it runs 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 consider how to choose a new air conditioner or furnace, consider:
- Lower energy costs: Higher-efficiency and right-sized systems can lower electricity use.
- Initial cost: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can help reduce long-term energy costs.
- Local utility costs: Areas with higher electricity rates may see greater 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 harsh winter weather or extremely hot summers.
- Length of home ownership: 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.
- Financial incentives: 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
What does this look like in a real world example?
Picture 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 only matched the previous unit. Next door, the second homeowner installs a properly sized, mid-efficiency 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 properly matched to the home's needs.
Choose the HVAC Professional Who Designs Personalized Solutions
Replacing your HVAC system should involve more than selecting the unit with the highest efficiency rating. An ideal system is one that meets your home’s heating and cooling requirements.
At JW Brager Heating and Cooling, our knowledgeable technicians perform an HVAC load calculation. Our team will evaluate your home's layout and construction, your household's comfort goals and recommend equipment that's designed specifically for your home—not simply the highest-capacity, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our team 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 JW Brager Heating and Cooling to get started. We'll evaluate your home, answer any questions and help you choose the correctly sized high-efficiency system that keeps your family comfortable for many years.