Choosing 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 focus on models with extremely high efficiency ratings.
Surely the most efficient system will provide the most comfort and lowest energy bills, right?
Not necessarily.
Efficiency ratings aren’t the only thing that matters when it comes to new air conditioner installation or installing a new furnace. Even though many focus only on 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 lasting performance. The best HVAC system for your home delivers energy 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 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), indicates how efficiently an air conditioner cools your home over a standard cooling season. A SEER2 rating is the updated version of SEER, using evaluation methods that better reflect real-world operating conditions. Most new air conditioners have a SEER2 designation, simply because this is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by AFUE, which stands for Annual Fuel Utilization Efficiency. As with 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.
That said, high numbers don't automatically guarantee lower utility bills. Real-world heating and air conditioner efficiency depends on more than just efficiency ratings, including the quality of the installation, the quality of your ductwork, how much insulation your home has, thermostat settings and, most importantly, system sizing. Even the highest-rated system cannot operate at its best if it is oversized or undersized for the home.
Why HVAC System Size Matters More Than You Probably Think
Many assume a higher-capacity 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. The truth is, new heating system installation or a new air conditioner should be chosen based on your home's true heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable companies complete an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation evaluates many details that affect your home's heating and cooling requirements, including:
- Total square footage
- Room height
- Window size and orientation
- Home insultation levels
- Drafts and air leakage
- Local 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 evenly while pulling out excess humidity. That means steadier temperatures, better indoor comfort and improved indoor humidity management. It also helps the equipment to perform more effciently, reducing unnecessary wear that can reduce its service life or lead to costly breakdowns.
When HVAC equipment is the right size for your home, you get improved comfort and more dependable performance.
Problems with Oversized and Undersized Heating and Cooling Systems
It might be tempting to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. However, that’s rarely a good investment.
HVAC systems that are too large or undersized can create comfort problems, increase operating costs 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 starts and stops often, reducing efficiency and increasing wear.
- Humidity problems: Oversized air conditioners reach the set temperature too fast to remove indoor humidity from the air.
- Uneven temperatures: Some rooms feel too cool while others never feel comfortable.
- Increased wear and tear: Even though the system reaches the target temperature rapidly, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Long run times: The system stays on for extended periods trying to reach the set temperature, which also causes unnecessary wear and tear.
- Difficulty reaching thermostat settings: Your home may never feel as cool as you want during hot weather or feel too cool during winter.
- Increased energy consumption: Running almost constantly can increase monthly energy expenses.
- Added strain during extreme weather: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the risk of breakdowns.
Finding the Right Balance Between Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, remember that you don't necessarily need the most efficient model on the market.
In many cases, a correctly sized, mid-efficiency heating and cooling system will deliver better performance than an oversized premium system because it functions 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 future plans.
As you think about how to choose a new air conditioner or furnace, consider:
- 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.
- Local utility costs: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Your local climate: It's crucial your heating or cooling system has adequate 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 be worth the investment.
- Rebates and tax credits: Manufacturer promotions, {utility|equipment rebates and tax credits can offset the overall cost of qualifying equipment.
Real-World Comparison: High Seer vs. Right System Size
What does this look like in the real world?
Imagine two neighboring homes.
In one, 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-efficiency system after completing a Manual J calculation.
Although the second system has a lower 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 properly matched to the home's needs.
Work With an HVAC Professional Who Designs Personalized Solutions
An HVAC replacement should involve more than selecting a system with the highest efficiency rating. An ideal system is one that meets your household heating and cooling requirements.
At Northglenn Heating & Air Conditioning, our knowledgeable technicians perform an HVAC load calculation. Our team will evaluate your home's design, your household's heating and cooling preferences and recommend equipment that's designed specifically for your home—not simply the highest-capacity, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our team 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 Northglenn Heating & Air Conditioning today. Our team will evaluate your home, answer any questions and help you choose the properly sized energy-efficient system that keeps your family comfortable for many years.