Choosing a new AC or furnace can be intimidating. If you want 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 will provide the most comfort and lowest energy bills, right?
It’s not quite that simple.
Energy efficiency isn't the only thing to think about when it comes to new air conditioner installation or furnace replacement. While many homeowners focus only on efficiency ratings, proper HVAC system sizing is just as, if not more important for your home's comfort and your energy bills.
Proper sizing also influences humidity control and system longevity. The best HVAC system for your home combines energy efficiency and proper sizing.
In this blog, 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 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), shows how effectively a cooling system cools your home over a typical cooling season. A SEER2 rating is the updated version of SEER, using evaluation methods that better simulate 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 short 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 keep you comfortable than lower-rated systems under standardized laboratory testing.
However, high numbers don't automatically 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, proper HVAC system sizing. Even the highest-rated 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 Think
Many assume a larger air conditioner or furnace will work the best or that they should simply replace their old HVAC system with a unit of the same capacity. In reality, new heating system installation or a new air conditioner 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 technicians complete 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 load, including:
- Total square footage
- Room height
- Window size and placement
- Home insultation levels
- Drafts and air leakage
- Local climate
- Household occupants
- Heat produced from appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home more uniformly while removing excess humidity. That means more even temperatures, better indoor comfort and improved humidity control. Proper sizing also helps the equipment to run more effciently, reducing excessive wear and tear that can cause it to wear it out sooner or lead to costly breakdowns.
When your heating or cooling system is the right size for your home, you get improved comfort and more reliable operation.
Problems Caused by Oversized and Undersized Systems
Many homeowners are tempted to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. However, that’s rarely a smart choice.
heating and cooling systems that are too large or smaller than your home requires 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 work quickly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear and tear.
- Reduced humidity control: Oversized air conditioners finish cooling cycles too soon to remove enough moisture from the air.
- Hot and cold spots: Some rooms feel too cool while others stay too warm.
- 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 can have the opposite problem:
- Long run times: The system operates almost continuously trying to reach the desired temperature, which also causes extra strain.
- Difficulty maintaining the desired temperature: Your home may feel cool enough during hot weather or never feel warm enough in cold weather.
- Higher energy use: Running almost constantly can increase monthly energy expenses.
- Added strain during extreme weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing wear and the chance of failure.
Finding the Right Balance Between 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 most efficient model on the market.
More often than not, a professionally sized, mid-efficiency HVAC system will provide better results than an overly large 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 long-term goals.
As you think about how to choose a new air conditioner or furnace, think about:
- Energy savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Initial cost: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can reduce long-term energy costs.
- Energy prices: Areas with more expensive electricity may see greater long-term savings from higher-efficiency units.
- Climate: It's crucial your heating or cooling system has adequate capacity to handle areas with very cold winters or extremely hot summers.
- Length of home ownership: If you plan to stay in your home for many years, the long-term energy savings of a higher-efficiency unit may offset the investment.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can reduce the overall cost of qualifying equipment.
Real-World Example: High Seer vs. Right System Size
How does this play out 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. Next door, the second homeowner installs a correctly sized, mid-efficiency system after completing a Manual J calculation.
Although the second system has a lesser efficiency rating on paper, it may deliver lower operating costs, better home comfort, more effective humidity control and last longer because it's properly matched to the home's needs.
Choose the Local HVAC Professional Who Designs Personalized Solutions
HVAC replacent or installation should involve much more than selecting the unit with the highest efficiency rating. The best system is one that meets your heating and cooling requirements.
At Dave's Diversified Services, our skilled HVAC experts 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 properly matched for your home—not simply the biggest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts will help you identify any available rebates or tax incentives and provide information about HVAC financing options that make energy-efficient HVAC systems more accessible for all budgets.
Schedule an HVAC consultation online with Dave's Diversified Services today. Our team will 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.