Shopping for a new air conditioning system or furnace can feel overwhelming. When you're looking to find the best HVAC system for your home, it's natural to focus on models with extremely high efficiency ratings.
Surely the most efficient equipment will provide the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
Energy efficiency isn't the only thing to think about when it comes to new air conditioner installation or installing a new furnace. Even though many focus only on {energy efficiency|efficiency ratings, proper {HVAC system sizing is often even more important for your home's comfort and your energy bills.
Proper sizing directly impacts humidity control and long-term reliability. The best HVAC system for your home delivers energy efficiency and correct 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 select 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 typical cooling season. A SEER2 rating is the newer version of SEER, using test procedures that better simulate real-world operating conditions. Nearly all 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 an AFUE rating, which is short for Annual Fuel Utilization Efficiency. Like SEER and SEER2, 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.
However, high numbers don't necessarily guarantee lower utility bills. Actual heating and air conditioner efficiency depends on more than just efficiency ratings, including the way the system is installed, the quality of your ductwork, insulation levels, thermostat settings and, most importantly, system sizing. Even the highest-efficiency system cannot operate at its best if it is oversized or smaller than needed for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a bigger air conditioner or furnace will heat or cool a home better or that they should simply replace their old HVAC system with a new one the same size. In reality, 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 your existing equipment.
That's why reputable contractors perform 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 requirements, including:
- Overall square footage
- Ceiling height
- Window size and direction
- Home insultation levels
- Air infiltration
- Regional climate
- Household occupants
- Heat produced from appliances and lighting
- Air duct condition
A properly sized air conditioner runs for enough time to cool your home consistently while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved humidity control. This also allows the equipment to operate more effciently, reducing strain that can cause it to wear it out sooner or lead to more repairs and higher repair costs.
When a furnace or AC is the right size for your home, you get better comfort and more dependable performance.
Problems Caused by Oversized and Undersized Systems
It might be tempting to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. The truth is, that’s rarely a good investment.
HVAC systems that are too large or smaller than your home requires can create comfort issues, increase utility costs 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 performs efficiently.
- Short cycling: An oversized HVAC system starts and stops often, reducing efficiency and increasing wear and tear.
- Humidity problems: Oversized air conditioners finish cooling cycles too soon to remove enough moisture from the air.
- Hot and cold spots: Some rooms become too cold while others never feel comfortable.
- Increased wear and tear: Even though the system heats or cools your home fast, 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:
- Continuous operation: The system runs for long periods trying to reach the thermostat setting, which also causes extra strain.
- Difficulty maintaining the desired temperature: Your home may feel cool enough during hot weather or feel too cool during winter.
- Increased energy consumption: Running for extended periods can increase monthly energy expenses.
- Extra stress during severe weather: HVAC systems that are too small can work harder in extreme temperatures, increasing equipment wear 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, remember that you don't automatically need the top-efficiency model on the market.
Often, a properly sized, mid-efficiency HVAC 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 matched for your home, your budget, your climate and your future plans.
When deciding how to choose a new air conditioner or furnace, consider:
- Efficiency savings: Higher-efficiency and right-sized systems can decrease electricity use.
- Upfront investment: High-efficiency AC and heating systems often cost more initially than mid-range models but can reduce long-term energy costs.
- Energy prices: Areas with higher utility costs may see more significant long-term savings from higher-efficiency units.
- Your local climate: It's essential your heating or cooling system has adequate capacity to handle areas with extremely cold winters or very hot summers.
- Time you plan to own the home: If you plan to stay 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 reduce the overall cost of higher-efficiency systems.
Real-World Example: High Seer vs. Right System Size
How does this work in the real world?
Suppose there are two neighboring homes.
In the first, the homeowner chooses a premium high-efficiency HVAC system that's too big because the contractor simply matched the previous unit. At the neighboring home, an HVAC professional installs a correctly sized, moderate-efficiency system after completing a Manual J calculation.
Although the second system has a more modest efficiency rating on paper, it may deliver lower operating costs, better home comfort, improved humidity control and last longer because it's appropriately sized to the home's needs.
Choose the Local HVAC Professional Who Designs Personalized Solutions
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 Classic Air, our experienced professionals perform an HVAC load calculation. Our team will evaluate your home's size and layout, your household's comfort needs and recommend equipment that's right for your home—not simply the biggest, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts 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 Classic Air to get started. 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 the long haul.