Shopping for a new air conditioning system or furnace can be stressful. When you're looking to find the best HVAC system for your home, it's understandable 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.
High efficiency isn't the only thing that matters when it comes to new air conditioner installation or installing a new furnace. Although many people focus only on energy efficiency, proper HVAC system sizing is equally, if not more important for your home's comfort and your energy bills.
Proper sizing also influences humidity control and long-term reliability. The best HVAC system for your home balances 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 recommending the best HVAC system for your home.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), shows how effectively an AC cools your home over a normal cooling season. A SEER2 rating is the newer version of SEER, using evaluation methods that better represent real-world operating conditions. Most new air conditioners have a SEER2 rating, simply because that is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by something called AFUE, which is short for Annual Fuel Utilization Efficiency. Like 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.
Even so, high ratings 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 state of your ductwork, how much insulation your home has, thermostat settings and, most importantly, system sizing. Even the most efficient system cannot perform as intended if it is bigger than necessary or undersized for the home.
Why HVAC System Size Matters More Than You Probably Think
Many assume a bigger air conditioner or furnace will make their home the most comfortable or that they should just replace their old HVAC system with a same-sized replacement. Actually, 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 size of the previous unit.
That's why reputable technicians conduct 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 comfort needs, including:
- Home square footage
- Ceiling height
- Window size and orientation
- Insulation
- Air infiltration
- Regional climate
- Household occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs through longer cooling cycles to cool your home evenly while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved moisture control. It also helps the equipment to run more effciently, reducing strain that can cause it to wear it out sooner or lead to costly breakdowns.
When a furnace or AC is properly sized, you get greater comfort and more reliable operation.
Problems Caused by Oversized and Undersized HVAC Equipment
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 good investment.
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 performs efficiently.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing wear.
- Poor humidity removal: Oversized air conditioners finish cooling cycles too soon to remove enough moisture from the air.
- Hot and cold spots: Some rooms get too cold while others never feel comfortable.
- Increased 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.
Cons Associated with 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 unnecessary wear and tear.
- Difficulty maintaining the desired temperature: Your home may feel cool enough during hot weather or feel too cool during winter.
- Increased energy consumption: Running almost constantly can increase utility bills.
- Greater strain on very hot or cold days: HVAC systems that are too small can work harder in extreme temperatures, increasing component strain and the risk of breakdowns.
Why You Should Balance HVAC System 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 top-efficiency model on the market.
More often than not, a professionally sized, mid-efficiency heating and cooling system will outperform an overly large premium system because it runs the way it was designed to.
Thesmartest choice is an energy-efficient HVAC system that's properly sized for your home, your budget, your climate and your future plans.
As you think about how to choose a new air conditioner or furnace, keep these factors in mind:
- Lower energy costs: 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.
- Electricity rates: Areas with higher electricity rates may see more significant long-term savings from higher-efficiency units.
- Your local climate: It's important 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 justify the investment.
- Financial incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can lower the overall cost of higher-efficiency systems.
Real-World Comparison: High Seer vs. Right System Size
How does this work in a real world example?
Picture two neighboring homes.
In the first, the homeowner chooses a premium high-efficiency HVAC system that's too big 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, mid-SEER or AFUE system after completing a Manual J calculation.
Even though the second system has a lesser efficiency rating on paper, it may provide lower operating costs, better home comfort, improved humidity control and have a longer lifespan because it's correctly matched to the home's needs.
Work With an HVAC Professional Who Designs Personalized Solutions
Replacing your HVAC system should involve more than selecting a model with the highest efficiency rating. The best system is one that meets your household heating and cooling requirements.
At Giordanos Heating and Air Conditioning, our experienced professionals perform an HVAC load calculation. We'll evaluate your home's design, your household's comfort needs 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 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 Giordanos Heating and Air Conditioning today. We'll gladly evaluate your home, answer your questions and help you choose the right-sized high-efficiency system that keeps your family comfortable for years to come.