Shopping for a new air conditioner or furnace can feel overwhelming. If you're trying to find the best HVAC system for your home, it's understandable to focus on models with the highest efficiency ratings.
After all, the most efficient equipment will provide the most comfort and lowest energy bills, right?
Not necessarily.
Efficiency ratings aren’t the only thing you should consider when it comes to new air conditioner installation or furnace replacement. Although many people focus only on {energy efficiency|efficiency ratings, proper {HVAC system sizing is equally, if not more important for your home's comfort and your power bills.
Proper sizing has a major impact on humidity control and long-term reliability. The best HVAC system for your home balances energy 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 qualified HVAC contractors consider both when helping you choose 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), measures how effectively a cooling system cools your home over a typical cooling season. A SEER2 rating is the current version of SEER, using testing methods that better reflect real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because that is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is measured by an AFUE rating, which is short for Annual Fuel Utilization Efficiency. Similar to 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.
That said, high ratings don't by themselves 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 most efficient system cannot perform as intended if it is oversized or undersized for the home.
Why Correct HVAC System Sizing Matters More Than You Think
Many assume a higher-capacity 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. The truth is, 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 the previous unit.
That's why reputable contractors conduct an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation analyzes many factors that affect your home's heating and cooling requirements, including:
- Home square footage
- Ceiling height
- Window size and placement
- Insulation
- Air leakage
- Local climate
- Number of occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs through longer cooling cycles 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 shorten its lifespan or lead to frequent or expensive repairs.
When a furnace or AC is correctly sized, you get improved comfort and more reliable operation.
Problems with Oversized and Undersized HVAC Equipment
It might be tempting to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. The truth is, that often isn't a good investment.
HVAC systems that are bigger than your home needs or undersized can create indoor comfort challenges, 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 delivers the best comfort.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear and tear.
- Humidity problems: Oversized air conditioners cool your home too quickly to remove indoor humidity from the air.
- Hot and cold spots: Some rooms become too cold while others never feel comfortable.
- Additional equipment wear: Even though the system works quickly, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- 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 not feel comfortable during hot weather or never feel warm enough in cold weather.
- Increased energy consumption: Running nonstop can increase energy costs.
- Added strain during extreme weather: HVAC systems that are too small can work harder 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 most efficient model on the market.
In many cases, a professionally sized, mid-efficiency heating and cooling system will deliver better performance than an oversized premium system because it operates 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.
When deciding how to choose a new air conditioner or furnace, consider:
- Energy savings: Higher-efficiency and right-sized systems can lower electricity use.
- Purchase price: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can help reduce long-term energy costs.
- Electricity rates: Areas with more expensive electricity may see better long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's important your heating or cooling system has adequate capacity to handle areas with extremely cold winters or very hot summers.
- How long you'll 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.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can offset the overall cost of high-efficiency HVAC equipment.
Real-World Situation: High Seer vs. Right System Size
How does this play out in a real world example?
Imagine 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 only matched the previous unit. The other homeowner installs a properly sized, mid-efficiency system after completing a Manual J calculation.
Even though the second system has a lower efficiency rating on paper, it may deliver lower operating costs, better home comfort, more effective humidity control and last longer because it's appropriately sized to the home's needs.
Choose the HVAC Professional Who Designs Personalized Solutions
HVAC replacent or installation should involve more than selecting a model with the highest efficiency rating. An ideal system is one that meets your home’s heating and cooling requirements.
At Dearing's Service & Solutions, our skilled HVAC experts perform an HVAC load calculation. We'll carefully evaluate your home's layout and construction, your household's comfort goals and recommend equipment that's designed specifically for your home—not simply the largest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will connect you with any available rebates or tax incentives 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 Dearing's Service & Solutions now. Our team will evaluate your home, answer any questions and help you choose the properly sized efficient system that keeps your family comfortable for years to come.