Shopping for a new air conditioner or furnace can feel overwhelming. If you want to find the best HVAC system for your home, it's natural 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?
Actually, that’s not always the case.
Efficiency ratings aren’t the only thing you should consider 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 just as, if not more important for your home's comfort and your energy bills.
Proper sizing also influences humidity control and system longevity. The best HVAC system for your home combines efficiency and proper sizing.
In thisblog, 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 trusted HVAC experts consider both when helping you choose the best HVAC system for your home.
What Does a High SEER Rating Actually Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), indicates how efficiently an AC cools your home over a typical cooling season. A SEER2 rating is the updated version of SEER, using evaluation methods 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 AFUE, which is for Annual Fuel Utilization Efficiency. Similar to SEER and SEER2, 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.
Even so, high ratings don't necessarily guarantee lower utility bills. Actual heating and air conditioner efficiency depends on more than just efficiency ratings, including the quality of the installation, the state of your ductwork, your home's insulation, thermostat settings and, most importantly, proper HVAC system sizing. Even the most efficient system cannot perform as intended if it is oversized or too small for the home.
Why Correct HVAC System Sizing Matters More Than You Think
Many assume a larger air conditioner or furnace will heat or cool a home better or that they should just replace their old HVAC system with a new one the same size. Actually, new heating system installation or air conditioner replacement should be sized based on your home's actual heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable technicians perform an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation evaluates many variables that impact 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 produced from appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home evenly while eliminating excess humidity. That means more even temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to perform more effciently, reducing unnecessary wear that can cause it to wear it out sooner or lead to more repairs and higher repair costs.
When HVAC equipment is properly sized, you get better comfort and more reliable operation.
Problems with Oversized and Undersized HVAC Equipment
You may be tempted to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. However, that often isn't a good investment.
HVAC systems that are bigger than necessary or too small 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 works well.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing wear and tear.
- Poor humidity removal: Oversized air conditioners finish cooling cycles too soon to remove indoor humidity from the air.
- Inconsistent temperatures: Some rooms get too cold while others aren’t ever cool enough.
- Increased wear and tear: Even though the system heats or cools your home fast, those frequent starts and stops 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 operates almost continuously trying to reach the set temperature, which also causes extra strain.
- Trouble reaching the thermostat setting: Your home may not feel comfortable during hot weather or always feel chilly in the winter.
- Increased energy consumption: Running almost constantly can increase utility bills.
- Extra stress during severe weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing component strain and the likelihood of repairs.
Why You Should Balance HVAC System Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, don't forget that you don't always need the most efficient model on the market.
In many cases, a correctly sized, mid-efficiency HVAC system will deliver better performance than an oversized premium system because it operates the way it was designed to.
Thebest choice is an energy-efficient HVAC system that's correctly sized for your home, your budget, your climate and your long-term needs.
When deciding how to choose a new air conditioner or furnace, think about:
- Efficiency savings: Higher-efficiency and right-sized systems can decrease electricity use.
- Initial cost: High-efficiency AC and heating systems often cost more initially than mid-range models but can lower long-term energy costs.
- Electricity rates: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Your local climate: It's important your heating or cooling system has adequate capacity to handle areas with very cold winters or extremely hot summers.
- Time you plan to own the home: If you expect to live in your home for many years, the long-term energy savings of a higher-efficiency unit may be worth the investment.
- Available rebates or tax incentives: 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
What does this look like in a real world example?
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 replaced it with the same size system as the previous unit. At the neighboring home, an HVAC professional installs a properly sized, mid-SEER or AFUE 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 have a longer lifespan because it's correctly matched to the home's needs.
Choose the Local HVAC Professional Who Designs the Right Solution
Replacing your HVAC system should involve more than selecting the unit with the highest efficiency rating. An ideal system is one that meets your household heating and cooling requirements.
At H&C Heating and Cooling, our experienced professionals perform an HVAC load calculation. We'll carefully evaluate your home's size and layout, your household's comfort goals and recommend equipment that's properly matched for your home—not simply the biggest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our team 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 H&C Heating and Cooling to get started. Our team will evaluate your home, answer your questions and help you choose the correctly sized energy-efficient system that keeps your family comfortable for many years.