Shopping for a new air conditioner or furnace can be intimidating. When you're looking to find the best HVAC system for your home, it's common to focus on models with extremely high efficiency ratings.
Surely the most efficient heating and cooling system should deliver the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
High efficiency isn't the only thing you should consider 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 power bills.
Proper sizing also influences humidity control and long-term reliability. The best HVAC system for your home combines energy efficiency and correct sizing.
In thisarticle, 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 experienced HVAC professionals consider both when helping you select 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), shows how efficiently an air conditioner cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using evaluation methods that better simulate real-world operating conditions. Most new air conditioners have a SEER2 efficiency 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 cooling efficiency 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 ratings don't by themselves 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, your home's insulation, thermostat settings and, most importantly, proper HVAC system sizing. Even the highest-rated system cannot operate at its best 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 higher-capacity air conditioner or furnace will make their home the most comfortable or that they should just replace their old HVAC system with a unit of the same capacity. Actually, new heating system installation or air conditioner replacement should be sized based on your home's current heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable technicians perform an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation evaluates many factors that affect your home's comfort needs, including:
- Home square footage
- Room height
- Window size and direction
- Insulation
- Drafts and air leakage
- Local climate
- Household occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs for enough time to cool your home evenly while pulling out excess humidity. That means more even temperatures, better indoor comfort and improved humidity control. It also helps the equipment to operate more effciently, reducing excessive wear and tear that can reduce its service life or lead to costly breakdowns.
When your heating or cooling system is the right size for your home, you get improved comfort and more dependable performance.
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. The truth is, that’s rarely a great idea.
heating and cooling systems that are bigger than your home needs or undersized can create comfort issues, increase energy expenses 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 works well.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing equipment strain.
- Reduced humidity control: Oversized air conditioners finish cooling cycles too soon to remove indoor humidity from the air.
- Inconsistent temperatures: Some rooms get too cold while others never feel comfortable.
- Increased wear and tear: Even though the system works quickly, those constant cycles can cause avoidable breakdowns due to the strain.
Cons Associated with Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Continuous operation: The system operates almost continuously trying to reach the thermostat setting, which also causes extra strain.
- Difficulty maintaining the desired temperature: Your home may never feel as cool as you want during hot weather or never feel warm enough in cold weather.
- Increased energy consumption: Running nonstop can increase monthly energy expenses.
- Extra stress during severe weather: HVAC systems that are too small can run extremely hard 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, keep in mind that you don't automatically need the most efficient model on the market.
Often, a properly sized, mid-efficiency HVAC system will outperform an oversized premium system because it runs the way it was designed to.
Theideal choice is an energy-efficient HVAC system that's properly sized 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 lower electricity use.
- Initial cost: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can help reduce long-term energy costs.
- Local utility costs: Areas with higher utility costs may see greater 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 extremely 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 justify the investment.
- Available rebates or tax incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can lower 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 scenario?
Imagine two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system that's too big for the house because the contractor replaced it with the same size system as 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 lower efficiency rating on paper, it may provide 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 Local HVAC Professional Who Designs the Right Solution
Replacing your HVAC system should involve much more than selecting a model with the top efficiency rating. The right system is one that meets your household heating and cooling requirements.
At Pratt Brothers, our skilled HVAC experts 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 highest-capacity, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will help you identify any available rebates and 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 Pratt Brothers now. Our team will evaluate your home, answer your questions and help you choose the right-sized high-efficiency system that keeps your family comfortable for many years.