Shopping for a new AC or furnace can be intimidating. When you're looking to find the best HVAC system for your home, it's common to focus on models with the highest efficiency ratings.
After all, the most efficient system should deliver the most comfort and lowest energy bills, right?
Not necessarily.
High 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, proper HVAC system sizing is equally, if not more important for your home's comfort and your power bills.
Proper sizing also influences humidity control and long-term reliability. The best HVAC system for your home combines efficiency and proper sizing.
In this blog, 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 experienced HVAC professionals consider both when recommending the best HVAC system for your home.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), measures how effectively an AC cools your home over a typical cooling season. A SEER2 rating is the updated version of SEER, using evaluation methods that better represent real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because this is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is measured by something called AFUE, which is short for Annual Fuel Utilization Efficiency. As with 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.
That said, high numbers don't necessarily 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, how much insulation your home has, thermostat settings and, most importantly, proper HVAC system sizing. Even the most efficient system cannot deliver peak performance if it is oversized or too small for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a larger air conditioner or furnace will make their home the most comfortable or that they should simply replace their old HVAC system with a same-sized replacement. Actually, new heating system installation or a new air conditioner should be sized based on your home's current heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable technicians conduct an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation considers many factors that affect your home's heating and cooling load, including:
- Home square footage
- Room height
- Window size and orientation
- Home insultation levels
- Air infiltration
- Area climate
- Household occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs long enough to cool your home consistently while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. This also allows the equipment to operate more effciently, reducing unnecessary wear that can shorten its lifespan or lead to more repairs and higher repair costs.
When HVAC equipment is properly sized, you get better comfort and long-lasting performance.
Problems with Oversized and Undersized Systems
You may be tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. The truth is, that often isn't a great idea.
HVAC systems that are bigger than necessary or undersized can create comfort problems, 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 work quickly, but that doesn't mean it delivers the best comfort.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing equipment strain.
- Poor humidity removal: Oversized air conditioners reach the set temperature too fast to remove indoor humidity from the air.
- Inconsistent temperatures: Some rooms feel too cool while others never feel comfortable.
- More 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 can have the opposite problem:
- Long run times: The system operates almost continuously 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 always feel chilly in the winter.
- Greater energy usage: Running almost constantly can increase energy costs.
- Added strain during extreme weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing wear and the risk of breakdowns.
Why You Should Balance HVAC System Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, remember that you don't always need the top-efficiency model on the market.
More often than not, a professionally sized, mid-efficiency HVAC 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 correctly sized for your home, your budget, your climate and your long-term needs.
As you think about 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 cost more initially than mid-range models but can help reduce long-term energy costs.
- Local utility costs: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Climate: It's essential your heating or cooling system has enough capacity to handle areas with harsh winter weather or very 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 offset the overall cost of qualifying equipment.
Real-World Example: High Seer vs. Right System Size
How does this play out in a real world example?
Imagine two neighboring homes.
In the first, 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. At the neighboring home, an HVAC professional installs a correctly sized, mid-efficiency 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 have a longer lifespan because it's correctly matched to the home's needs.
Choose the Local HVAC Professional Who Designs Solutions Tailored to Your Home
HVAC replacent or installation should involve more than selecting a system with the highest efficiency rating. The best system is one that meets your heating and cooling requirements.
At Luikart Heating & Cooling, 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 designed specifically for your home—not simply the highest-capacity, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts will let you know about any available rebates and 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 Luikart Heating & Cooling today. We'll evaluate your home, answer your questions and help you choose the right-sized energy-efficient system that keeps your family comfortable for many years.