Shopping for a new air conditioning system or furnace can be stressful. If you want to find the best HVAC system for your home, it's natural to look for models with the highest efficiency ratings.
Surely the most efficient equipment should deliver 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 furnace replacement. Although many people focus only on energy efficiency, proper HVAC system sizing is often even more important for your home's comfort and your power bills.
Proper sizing has a major impact on humidity control and long-term reliability. The best HVAC system for your home combines efficiency and correct sizing.
In this article, 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 trusted HVAC experts consider both when helping you choose the best HVAC system for your home.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), measures how efficiently an air conditioner cools your home over a normal cooling season. A SEER2 rating is the current version of SEER, using evaluation methods that better reflect real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because this rating 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 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 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-efficiency system cannot operate at its best if it is oversized or smaller than needed for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a higher-capacity air conditioner or furnace will work the best or that they should simply replace their old HVAC system with a new one the same size. In reality, new heating system installation or AC replacement should be chosen based on your home's actual heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable technicians complete an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation evaluates many variables that affect your home's heating and cooling requirements, including:
- Total square footage
- Room height
- Window size and placement
- Home insultation levels
- Drafts and air leakage
- Area climate
- Number of occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs long enough to cool your home consistently while eliminating 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 shorten its lifespan or lead to frequent or expensive repairs.
When HVAC equipment is the right size for your home, you get improved comfort and long-lasting performance.
Problems with Oversized and Undersized Systems
It might be tempting to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. The truth is, that's usually not a smart choice.
HVAC systems that are too large or smaller than your home requires can create indoor comfort challenges, increase operating costs and reduce efficiency regardless of their SEER rating.
Issues Created by Oversized HVAC Systems
An oversized air conditioner or heating system may reach the thermostat setting fast, 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 cool your home too quickly to remove excess moisture from the air.
- Hot and cold spots: Some rooms get too cold while others aren’t ever cool enough.
- 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.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Long run times: The system runs for long periods trying to reach the set temperature, which also causes extra strain.
- Trouble reaching the thermostat setting: 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 utility bills.
- Added strain during extreme weather: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the likelihood of repairs.
Balancing Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, don't forget that you don't necessarily need the top-efficiency model on the market.
Often, a correctly sized, mid-efficiency heating and cooling system will provide better results than an overly large premium system because it operates the way it was designed to.
Thesmartest 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, consider:
- Efficiency savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Initial cost: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can lower long-term energy costs.
- Electricity rates: Areas with higher utility costs may see more significant long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's important your heating or cooling system has the right capacity to handle areas with harsh winter weather or very 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 be worth the investment.
- Available rebates or tax incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can reduce 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?
Suppose there are two neighboring homes.
In the first, 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 right-sized, moderate-efficiency system after completing a Manual J calculation.
While the second system has a more modest efficiency rating on paper, it may deliver 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 highest efficiency rating. An ideal system is one that meets your heating and cooling requirements.
At Siloam Springs Heating & AC, our knowledgeable technicians perform an HVAC load calculation. Our team will evaluate your home's design, your household's comfort goals and recommend equipment that's right for your home—not simply the biggest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts will let you know about 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 Siloam Springs Heating & AC now. We'll gladly evaluate your home, answer any questions and help you choose the correctly sized efficient system that keeps your family comfortable for many years.
