Choosing a new air conditioner or furnace can be stressful. If you're trying to find the best HVAC system for your home, it's common to focus on models with extremely high efficiency ratings.
After all, 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 that matters 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 has a major impact on humidity control and system longevity. The best HVAC system for your home combines energy efficiency and proper sizing.
In thisguide, 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.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), shows 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 represent real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because this rating is the current rating system for cooling equipment.
Fuel-burning heating system efficiency is measured by AFUE, which is short for Annual Fuel Utilization Efficiency. Like SEER and SEER2, higher AFUE ratings indicate a high-efficiency HVAC system that uses less electricity to heat your home than lower-rated systems under standardized laboratory testing.
However, high ratings don't automatically guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on more than just efficiency ratings, including the installation quality, the state of your ductwork, insulation levels, thermostat settings and, most importantly, system sizing. Even the most efficient system cannot operate at its best if it is bigger than necessary or smaller than needed for the home.
Why Correct HVAC System Sizing Matters More Than You Probably Think
Many assume a larger air conditioner or furnace will make their home the most comfortable or that they should just replace their old HVAC system with a new one the same size. The truth is, 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 the previous unit.
That's why reputable companies perform an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation analyzes many details that impact your home's comfort needs, including:
- Overall square footage
- Ceiling height
- Window size and placement
- Home insultation levels
- Air leakage
- Regional climate
- Number of occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs through longer cooling cycles to cool your home evenly while removing excess humidity. That means more consistent temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to perform more effciently, reducing strain that can cause it to wear it out sooner or lead to costly breakdowns.
When your heating or cooling system is correctly sized, you get greater comfort and more reliable operation.
Problems Caused by Oversized and Undersized Systems
Many homeowners are tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. The truth is, that’s rarely 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.
Drawbacks of 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 cycles repeatedly, reducing efficiency and increasing wear.
- Reduced humidity control: Oversized air conditioners cool your home too quickly to remove indoor humidity from the air.
- Uneven temperatures: Some rooms become too cold while others aren’t ever cool enough.
- Increased wear and tear: Even though the system heats or cools your home fast, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Continuous operation: The system operates almost continuously trying to reach the desired temperature, which also causes unnecessary wear and tear.
- Difficulty reaching thermostat settings: Your home may not feel comfortable during hot weather or never feel warm enough in cold weather.
- Greater energy usage: Running for extended periods can increase energy costs.
- Extra stress during severe weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing wear and the risk of breakdowns.
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 automatically need the highest-efficiency model on the market.
Often, a correctly sized, mid-efficiency heating and cooling system will deliver better performance than an overly large premium system because it operates 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 needs.
When deciding how to choose a new air conditioner or furnace, keep these factors in mind:
- Efficiency savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Upfront investment: 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 more expensive electricity may see greater long-term savings from higher-efficiency units.
- Your local climate: It's essential your heating or cooling system has enough capacity to handle areas with very cold winters or extremely 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 offset the investment.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can lower the overall cost of high-efficiency HVAC equipment.
Real-World Comparison: High Seer vs. Right System Size
What does this look like in a real world example?
Suppose there are two neighboring homes.
In the first, the homeowner chooses a premium high-efficiency HVAC system has far more capacity than the home needs because the contractor replaced it with the same size system as the previous unit. Next door, the second homeowner installs a properly 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 deliver lower operating costs, better home comfort, improved humidity control and last longer because it's appropriately sized to the home's needs.
Work With an HVAC Professional Who Designs Personalized Solutions
An HVAC replacement should involve much more than selecting a model with the top efficiency rating. An ideal system is one that meets your household heating and cooling requirements.
At Allstar Heating & Air Conditioning, our knowledgeable technicians perform an HVAC load calculation. Our team will evaluate your home's layout and construction, your household's heating and cooling preferences and recommend equipment that's properly matched for your home—not simply the biggest, fanciest unit or the one with the highest AFUE or SEER2 rating.
Our HVAC experts will help you identify any available tax rebates 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 Allstar Heating & Air Conditioning today. We'll gladly evaluate your home, answer your questions and help you choose the right-sized energy-efficient system that keeps your family comfortable for the long haul.