Choosing a new air conditioner 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 the highest efficiency ratings.
Surely the most efficient heating and cooling system provides the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
High efficiency isn't the only thing to think about 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 often even more important for your home's comfort and your utility bills.
Proper sizing directly impacts humidity control and lasting performance. The best HVAC system for your home delivers energy efficiency and proper sizing.
In thisblog, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why correct HVAC size 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), shows how effectively an AC cools your home over a normal cooling season. A SEER2 rating is the current version of SEER, using testing methods that better simulate real-world operating conditions. Most new air conditioners have a SEER2 designation, simply because this is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by an AFUE rating, which stands for Annual Fuel Utilization Efficiency. As with SEER and SEER2, 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.
Even so, high numbers don't by themselves guarantee lower utility bills. Real-world heating and air conditioner efficiency depends on several key factors, including the installation quality, the quality 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 oversized or undersized for the home.
Why Proper HVAC Sizing Matters More Than Most Homeowners Realize
Many assume a larger air conditioner or furnace will make their home the most comfortable or that they should simply replace their old HVAC system with a same-sized replacement. In reality, new heating system installation or a new air conditioner should be selected based on your home's current heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable contractors perform an HVAC load calculation, also called a Manual J calculation, before suggesting 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 placement
- Home insultation levels
- Air infiltration
- Local climate
- Household occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs long enough to cool your home evenly while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved moisture control. This also allows the equipment to operate 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 properly sized, you get better comfort and more dependable performance.
Problems with Oversized and Undersized Heating and Cooling Systems
You may be tempted to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. The truth is, that often isn't a great idea.
heating and cooling systems that are bigger than necessary 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 work quickly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear.
- Poor humidity removal: Oversized air conditioners cool your home too quickly to remove enough moisture from the air.
- Inconsistent temperatures: Some rooms feel too cool while others never feel comfortable.
- Additional equipment wear: Even though the system reaches the target temperature rapidly, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Issues Created by 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 unnecessary wear and tear.
- Difficulty maintaining the desired temperature: Your home may not feel comfortable during hot weather or feel too cool during winter.
- Greater energy usage: Running nonstop can increase utility bills.
- Greater strain on very hot or cold days: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the likelihood of repairs.
Finding the Right Balance Between Efficiency and Size
When trying to decide between a high SEER vs right-sized system, don't forget 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 overly large premium system because it runs 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 needs.
As you think about how to choose a new air conditioner or furnace, keep these factors in mind:
- Efficiency savings: 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.
- Energy prices: Areas with higher utility costs may see more significant long-term savings from higher-efficiency units.
- Climate: It's essential your heating or cooling system has enough capacity to handle areas with extremely 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 be worth 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 Example: High Seer vs. Right System Size
What does this look like in a real world example?
Suppose there are two neighboring homes.
At the first home, 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. Next door, the second homeowner installs a correctly sized, mid-efficiency system after completing a Manual J calculation.
Even though 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 last longer 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 right system is one that meets your home’s heating and cooling requirements.
At B&B Heating, Cooling, Plumbing & Electrical, our experienced professionals perform an HVAC load calculation. We'll carefully evaluate your home's layout and construction, your household's comfort needs and recommend equipment that's properly matched for your home—not simply the largest, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts will help you identify any available rebates and tax incentives and provide information about HVAC financing options that make high-efficiency systems more accessible for all budgets.
Schedule an HVAC consultation online with B&B Heating, Cooling, Plumbing & Electrical to get started. We'll evaluate your home, answer any questions and help you choose the properly sized energy-efficient system that keeps your family comfortable for the long haul.