Shopping for 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 focus on models with extremely high efficiency ratings.
Surely the most efficient heating and cooling system will provide the most comfort and lowest energy bills, right?
Not necessarily.
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, proper HVAC system sizing is just as, if not more important for your home's comfort and your utility bills.
Proper sizing also influences humidity control and long-term reliability. The best HVAC system for your home combines efficiency and proper sizing.
In thisarticle, 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 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 a cooling system cools your home over a normal cooling season. A SEER2 rating is the newer version of SEER, using testing methods that better reflect real-world operating conditions. Most new air conditioners have a SEER2 efficiency rating, simply because this rating is the new rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by an AFUE rating, which is for Annual Fuel Utilization Efficiency. Similar to SEER and SEER2, higher AFUE ratings indicate a high-efficiency HVAC system that uses less electricity to achieve indoor comfort than lower-rated systems under standardized laboratory testing.
Even so, high ratings don't necessarily guarantee lower utility bills. Actual heating and air conditioner efficiency depends on several key factors, including the way the system is installed, the state of your ductwork, how much insulation your home has, thermostat settings and, most importantly, system sizing. Even the highest-efficiency system cannot perform as intended if it is bigger than necessary or undersized for the home.
Why Correct HVAC System Sizing 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 same-sized replacement. In reality, new heating system installation or air conditioner replacement should be sized based on your home's actual heating and cooling needs—not just square footage or the size of your existing equipment.
That's why reputable technicians conduct an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation analyzes many variables that affect your home's heating and cooling load, including:
- Home square footage
- Ceiling height
- Window size and direction
- Home insultation levels
- Air leakage
- Local climate
- Number of occupants
- Heat produced from appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home evenly while eliminating excess humidity. That means more even temperatures, better indoor comfort and improved humidity control. This also allows the equipment to operate more effciently, reducing excessive wear and tear that can reduce its service life or lead to frequent or expensive repairs.
When your heating or cooling system is correctly sized, you get improved comfort and more dependable performance.
Problems Caused by Oversized and Undersized Heating and Cooling Systems
Many homeowners are tempted to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. However, that’s rarely a smart choice.
HVAC systems that are too large or smaller than your home requires can create comfort issues, increase energy expenses and reduce efficiency regardless of their SEER rating.
Common Problems With Oversized HVAC Systems
An oversized air conditioner or heating system may heat or cool rapidly, but that doesn't mean it works well.
- Short cycling: An oversized HVAC system starts and stops often, reducing efficiency and increasing wear and tear.
- High indoor humidity: Oversized air conditioners reach the set temperature too fast to remove indoor humidity from the air.
- Hot and cold spots: Some rooms get too cold while others aren’t ever cool enough.
- Additional equipment wear: Even though the system heats or cools your home fast, those constant cycles can cause avoidable breakdowns due to the strain.
Cons Associated with Undersized HVAC Systems
An undersized HVAC system can have the opposite problem:
- Long run times: The system runs for long periods trying to reach the set temperature, which also causes unnecessary wear and tear.
- Difficulty maintaining the desired temperature: Your home may never feel as cool as you want during hot weather or feel too cool during winter.
- Higher energy use: Running for extended periods can increase monthly energy expenses.
- Greater strain on very hot or cold days: HVAC systems that are too small can work harder in extreme temperatures, increasing wear and the likelihood of repairs.
Balancing Efficiency and Size
When trying to decide between a high SEER vs right-sized system, remember that you don't automatically need the highest-efficiency model on the market.
Often, a properly sized, mid-efficiency heating and cooling system will outperform an oversized premium system because it runs the way it was designed to.
Thebest choice is an energy-efficient HVAC system that's properly 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, think about:
- Lower energy costs: 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 help 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 extremely cold winters or intense summer heat.
- Length of home ownership: If you expect to live in your home for many years, the long-term energy savings of a higher-efficiency unit may offset the investment.
- Financial incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can offset the overall cost of high-efficiency HVAC equipment.
Real-World Situation: High Seer vs. Right System Size
How does this play out in the real world?
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 simply matched the previous unit. The other homeowner installs a properly sized, moderate-efficiency system after completing a Manual J calculation.
While the second system has a lower efficiency rating on paper, it may deliver 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 the Right Solution
An HVAC replacement should involve much more than selecting a system with the top efficiency rating. The right system is one that meets your home’s heating and cooling requirements.
At Integrity AC & Heating LLC, our experienced professionals perform an HVAC load calculation. We'll 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 biggest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will let you know about any available tax rebates and provide information about HVAC financing options that make energy-efficient HVAC systems more accessible for all budgets.
Schedule an HVAC consultation online with Integrity AC & Heating LLC now. We'll evaluate your home, answer your questions and help you choose the right-sized efficient system that keeps your family comfortable for years to come.
