Shopping for a new air conditioning system or furnace can be stressful. If you're trying 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 system should deliver the most comfort and lowest energy bills, right?
Not necessarily.
Energy efficiency isn't the only thing you should consider when it comes to new air conditioner installation or replacing your furnace. Although many people focus only on 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 lasting performance. 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 proper HVAC system sizing is so important and why qualified HVAC contractors consider both when recommending 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 air conditioner cools your home over a normal cooling season. A SEER2 rating is the updated version of SEER, using testing methods that better reflect real-world operating conditions. Nearly all new air conditioners have a SEER2 designation, simply because this is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by something called AFUE, which stands for Annual Fuel Utilization Efficiency. Similar to cooling efficiency ratings, 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.
That said, high ratings don't automatically guarantee lower utility bills. Actual heating and air conditioner efficiency depends on many factors, including the quality of the installation, the state of your ductwork, insulation levels, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot deliver peak performance if it is bigger than necessary or too small for the home.
Why Correct HVAC System Sizing Matters More Than You Probably Think
Many assume a larger 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. The truth is, new heating system installation or AC replacement should be sized based on your home's true heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable contractors complete an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation analyzes many variables that affect your home's heating and cooling requirements, including:
- Overall square footage
- Room height
- Window size and direction
- Home insultation levels
- 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 consistently while eliminating excess humidity. That means steadier temperatures, better indoor comfort and improved moisture control. This also allows the equipment to perform more effciently, reducing excessive wear and tear that can shorten its lifespan or lead to frequent or expensive repairs.
When your heating or cooling system is correctly sized, you get improved comfort and more reliable operation.
Problems with Oversized and Undersized 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 smart choice.
heating and cooling systems that are bigger than your home needs or undersized can create indoor comfort challenges, increase energy expenses 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.
- Poor humidity removal: Oversized air conditioners cool your home too quickly to remove excess moisture from the air.
- Uneven temperatures: Some rooms become too cold while others never feel comfortable.
- More 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 also can struggle:
- Long run times: The system operates almost continuously trying to reach the set temperature, which also causes unnecessary wear and tear.
- Difficulty maintaining the desired temperature: Your home may not feel comfortable during hot weather or always feel chilly in the winter.
- Higher energy use: Running for extended periods can increase monthly energy expenses.
- Extra stress during severe weather: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the risk of breakdowns.
Why You Should Balance HVAC System Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, keep in mind that you don't always need the highest-efficiency model on the market.
More often than not, a professionally sized, mid-efficiency heating and cooling system will deliver better performance than an oversized 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, think about:
- Lower energy costs: Higher-efficiency and right-sized systems can lower electricity use.
- Upfront investment: High-efficiency AC and heating systems often cost more initially than mid-range models but can help reduce long-term energy costs.
- Electricity rates: Areas with more expensive electricity may see more significant long-term savings from higher-efficiency units.
- Climate: It's crucial your heating or cooling system has adequate capacity to handle areas with harsh winter weather or extremely hot summers.
- Length of home ownership: If you intend to remain in your home for many years, the long-term energy savings of a higher-efficiency unit may offset 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 has far more capacity than the home needs because the contractor only 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 more modest efficiency rating on paper, it may provide lower operating costs, better home comfort, more effective humidity control and have a longer lifespan because it's appropriately sized to the home's needs.
Work With an HVAC Professional Who Designs Personalized Solutions
HVAC replacent or installation should involve more than selecting a model with the top efficiency rating. The best system is one that meets your household heating and cooling requirements.
At HCE Systems, our knowledgeable technicians 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 right for your home—not simply the largest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will help you identify 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 HCE Systems to get started. We'll evaluate your home, answer your questions and help you choose the properly sized high-efficiency system that keeps your family comfortable for years to come.