Shopping for a new AC or furnace can be stressful. When you're looking to find the best HVAC system for your home, it's understandable to focus on models with extremely high efficiency ratings.
Surely the most efficient heating and cooling system provides the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
High efficiency isn't the only thing to think about when it comes to new air conditioner installation or installing a new furnace. Although many people focus only on efficiency ratings, proper HVAC system sizing is equally, if not more important for your home's comfort and your utility bills.
Proper sizing has a major impact on humidity control and system longevity. The best HVAC system for your home balances energy efficiency and proper sizing.
In this article, 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 qualified HVAC contractors consider both when helping you select 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 efficiently a cooling system cools your home over a standard cooling season. A SEER2 rating is the updated version of SEER, using test procedures that better reflect real-world operating conditions. Most new air conditioners have a SEER2 rating, simply because this rating is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by something called AFUE, which is for Annual Fuel Utilization Efficiency. Similar to SEER and SEER2 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.
Even so, 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 quality of your ductwork, insulation levels, thermostat settings and, most importantly, system sizing. Even the highest-rated system cannot operate at its best if it is too large or undersized for the home.
Why Proper HVAC Sizing Matters More Than You Think
Many assume a bigger 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. In reality, new heating system installation or air conditioner replacement should be chosen 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 complete an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation considers many factors that affect your home's heating and cooling requirements, including:
- Total square footage
- Ceiling height
- Window size and direction
- Home insultation levels
- Drafts and air leakage
- Regional climate
- Number of occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs long enough to cool your home evenly while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to run more effciently, reducing unnecessary wear that can reduce its service life or lead to costly breakdowns.
When HVAC equipment is properly sized, you get better comfort and more dependable performance.
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. However, that's usually not a great idea.
heating and cooling 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.
Common Problems With Oversized HVAC Systems
An oversized air conditioner or heating system may reach the thermostat setting fast, but that doesn't mean it performs efficiently.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear and tear.
- Reduced humidity control: Oversized air conditioners cool your home too quickly to remove indoor humidity from the air.
- Uneven temperatures: Some rooms get too cold while others aren’t ever cool enough.
- More 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 also can struggle:
- Long run times: The system stays on for extended periods trying to reach the thermostat setting, which also causes additional wear.
- 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 nonstop can increase energy costs.
- 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.
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 always need the highest-efficiency model on the market.
In many cases, a correctly sized, mid-efficiency heating and cooling system will outperform an overly large premium system because it functions 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 long-term goals.
As you think about how to choose a new air conditioner or furnace, think about:
- Energy savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Upfront investment: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can lower long-term energy costs.
- Local utility costs: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's essential your heating or cooling system has adequate capacity to handle areas with extremely cold winters or extremely hot summers.
- 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 be worth the investment.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can lower the overall cost of higher-efficiency systems.
Real-World Example: High Seer vs. Right System Size
How does this work in a real world scenario?
Picture two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system has far more capacity than the home needs because the contractor replaced it with the same size system as 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 more modest efficiency rating on paper, it may provide lower operating costs, better home comfort, improved humidity control and have a longer lifespan because it's correctly matched to the home's needs.
Work With an HVAC Professional Who Designs Solutions Tailored to Your Home
An HVAC replacement should involve much more than selecting a system with the highest efficiency rating. The right system is one that meets your heating and cooling requirements.
At Parker County Cooling & Heating, our knowledgeable technicians perform an HVAC load calculation. We'll carefully evaluate your home's size and layout, your household's heating and cooling preferences and recommend equipment that's designed specifically for your home—not simply the largest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our team will help you identify any available rebates or 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 Parker County Cooling & Heating today. Our team will evaluate your home, answer any questions and help you choose the properly sized high-efficiency system that keeps your family comfortable for years to come.