Choosing a new air conditioner or furnace can be intimidating. If you want to find the best HVAC system for your home, it's common to focus on models with the highest efficiency ratings.
Surely the most efficient system should deliver the most comfort and lowest energy bills, right?
It’s not quite that simple.
Energy efficiency isn't the only thing you should consider when it comes to new air conditioner installation or installing a new furnace. Although many people focus only on {energy efficiency|efficiency ratings, proper {HVAC system sizing is often even 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 balances efficiency and proper sizing.
In thisarticle, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why correct HVAC 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 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 represent 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 evaluated by an AFUE rating, which is for Annual Fuel Utilization Efficiency. As with SEER and SEER2 ratings, 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.
That said, high numbers don't necessarily guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on more than just efficiency ratings, including the way the system is installed, the condition of your ductwork, insulation levels, thermostat settings and, most importantly, system sizing. Even the highest-efficiency system cannot deliver peak performance if it is bigger than necessary or too small for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a bigger air conditioner or furnace will make their home the most comfortable or that they should simply replace their old HVAC system with a new one the same size. The truth is, new heating system installation or AC replacement should be selected 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 contractors complete an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation evaluates many details that affect your home's heating and cooling load, including:
- Total square footage
- Ceiling height
- Window size and direction
- Home insultation levels
- Air infiltration
- Local climate
- Household occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs long enough to cool your home more uniformly while removing excess humidity. That means more even temperatures, better indoor comfort and improved moisture control. This also allows the equipment to perform more effciently, reducing unnecessary wear that can shorten its lifespan or lead to costly breakdowns.
When a furnace or AC is properly sized, you get greater comfort and more reliable operation.
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. However, that’s rarely a good investment.
heating and cooling systems that are too large or too small can create comfort problems, increase utility costs and reduce efficiency regardless of their SEER rating.
Common Problems With Oversized HVAC Systems
An oversized air conditioner or heating system may work quickly, but that doesn't mean it performs efficiently.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear.
- Poor humidity removal: Oversized air conditioners cool your home too quickly to remove excess moisture from the air.
- Hot and cold spots: Some rooms become too cold while others never feel comfortable.
- Additional equipment wear: Even though the system heats or cools your home fast, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Cons Associated with Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Long run times: The system operates almost continuously trying to reach the set temperature, which also causes additional wear.
- Difficulty reaching thermostat settings: Your home may never feel as cool as you want during hot weather or feel too cool during winter.
- Greater energy usage: Running for extended periods can increase utility bills.
- Added strain during extreme weather: HVAC systems that are too small can struggle in extreme temperatures, increasing wear and the likelihood of repairs.
Balancing Efficiency and Size
When trying to decide between a high SEER vs right-sized system, keep in mind that you don't automatically need the top-efficiency model on the market.
In many cases, a correctly sized, mid-efficiency heating and cooling system will provide better results than an oversized premium system because it functions 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 future plans.
As you consider how to choose a new air conditioner or furnace, keep these factors in mind:
- Lower energy costs: Higher-efficiency and right-sized systems can lower 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 important your heating or cooling system has the right capacity to handle areas with extremely cold winters or very hot summers.
- Length of home ownership: 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 offset the overall cost of high-efficiency HVAC equipment.
Real-World Comparison: High Seer vs. Right System Size
What does this look like in the real world?
Picture two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system that's too big for the house because the contractor simply matched 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.
Although the second system has a lower efficiency rating on paper, it may deliver lower operating costs, better home comfort, improved humidity control and have a longer lifespan because it's appropriately sized to the home's needs.
Choose the Local HVAC Professional Who Designs Personalized Solutions
Replacing your HVAC system should involve much more than selecting a system with the top efficiency rating. An ideal system is one that meets your heating and cooling requirements.
At Age Heating & Cooling, our experienced professionals 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, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will let you know about any available tax rebates and provide information about HVAC financing options that make energy-efficient HVAC systems more accessible for all budgets.
Schedule an HVAC consultation online with Age Heating & Cooling to get started. Our team will evaluate your home, answer your questions and help you choose the right-sized efficient system that keeps your family comfortable for years to come.
