Choosing a new air conditioning system or furnace can be intimidating. If you want to find the best HVAC system for your home, it's common to look for models with extremely high efficiency ratings.
After all, the most efficient heating and cooling system provides the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
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 {energy efficiency|efficiency ratings, proper {HVAC system sizing is just as, if not more important for your home's comfort and your utility bills.
Proper sizing has a major impact on humidity control and system longevity. The best HVAC system for your home delivers energy efficiency and correct 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 trusted HVAC experts 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), indicates how efficiently an air conditioner cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using testing methods that better simulate real-world operating conditions. Nearly all 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 measured 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.
However, high numbers 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, insulation levels, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot operate at its best if it is oversized or smaller than needed for the home.
Why HVAC System Size Matters More Than You Think
Many assume a bigger air conditioner or furnace will make their home the most comfortable or that they should simply replace their old HVAC system with a new one the same size. 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 companies conduct an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation analyzes many factors that impact your home's heating and cooling requirements, including:
- Overall square footage
- Ceiling height
- Window size and placement
- Home insultation levels
- Drafts and air leakage
- Regional climate
- Number of occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home consistently while eliminating excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to operate more effciently, reducing unnecessary wear that can reduce its service life or lead to more repairs and higher repair costs.
When your heating or cooling system is correctly sized, you get greater comfort and more reliable operation.
Problems Caused by Oversized and Undersized HVAC Equipment
Many homeowners are tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. The truth is, that's usually not a good investment.
HVAC systems that are bigger than necessary or too small can create indoor comfort challenges, increase utility costs and reduce efficiency regardless of their SEER rating.
Common Problems With Oversized HVAC Systems
An oversized air conditioner or heating system may reach the thermostat setting fast, but that doesn't mean it performs efficiently.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing wear and tear.
- Reduced humidity control: Oversized air conditioners cool your home too quickly to remove enough moisture from the air.
- Uneven temperatures: Some rooms feel too cool while others aren’t ever cool enough.
- Increased wear and tear: Even though the system reaches the target temperature rapidly, those constant cycles can cause avoidable breakdowns due to the strain.
Issues Created by Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Continuous operation: The system runs for long periods trying to reach the desired temperature, which also causes unnecessary wear and tear.
- Trouble reaching the thermostat setting: Your home may feel cool enough during hot weather or never feel warm enough in cold weather.
- Higher energy use: Running for extended periods can increase utility bills.
- Greater strain on very hot or cold days: HVAC systems that are too small can struggle in extreme temperatures, increasing wear and the risk of breakdowns.
Why You Should Balance HVAC System Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, don't forget that you don't automatically need the top-efficiency model on the market.
More often than not, a correctly sized, mid-efficiency heating and cooling system will provide better results than an oversized premium system because it operates 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 long-term needs.
As you consider how to choose a new air conditioner or furnace, consider:
- Energy savings: Higher-efficiency and right-sized systems can lower electricity use.
- Initial cost: High-efficiency AC and heating systems often cost more initially than mid-range models but can reduce long-term energy costs.
- Energy prices: Areas with higher electricity rates may see greater long-term savings from higher-efficiency units.
- Climate: It's crucial your heating or cooling system has the right capacity to handle areas with very cold winters or intense summer heat.
- How long you'll own the home: 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 offset the overall cost of qualifying equipment.
Real-World Situation: High Seer vs. Right System Size
How does this work in the real world?
Suppose there are two neighboring homes.
At the first home, the homeowner chooses a premium high-efficiency HVAC system that's too big because the contractor only matched the previous unit. Next door, the second homeowner installs a properly sized, mid-efficiency 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, more effective humidity control and have a longer lifespan because it's appropriately sized to the home's needs.
Choose the HVAC Professional Who Designs Solutions Tailored to Your Home
Replacing your HVAC system should involve more than selecting the unit with the highest efficiency rating. An ideal system is one that meets your heating and cooling requirements.
At Northglenn Heating & Air Conditioning, our experienced professionals perform an HVAC load calculation. We'll evaluate your home's design, your household's comfort goals and recommend equipment that's right for your home—not simply the largest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will connect you with 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 Northglenn Heating & Air Conditioning to get started. Our team will evaluate your home, answer your questions and help you choose the right-sized energy-efficient system that keeps your family comfortable for many years.