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 the highest efficiency ratings.
After all, the most efficient equipment 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 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 also influences humidity control and lasting performance. The best HVAC system for your home balances energy efficiency and correct 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 helping you choose the best HVAC system for your home.
High Seer Ratings: What Do They Mean?
A SEER rating, (Seasonal Energy Efficiency Ratio), indicates how effectively a cooling system cools your home over a typical cooling season. A SEER2 rating is the newer version of SEER, using test procedures that better reflect real-world operating conditions. Today’s 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 measured by an AFUE rating, which is short for Annual Fuel Utilization Efficiency. As with SEER and SEER2 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. Actual heating and air conditioner efficiency depends on many factors, including the quality of the installation, the condition of your ductwork, how much insulation your home has, thermostat settings and, most importantly, proper HVAC system sizing. Even the most efficient system cannot operate at its best if it is too large or smaller than needed for the home.
Why Proper HVAC Sizing Matters More Than You Probably Think
Many assume a larger air conditioner or furnace will work the best or that they should simply replace their old HVAC system with a unit of the same capacity. Actually, new heating system installation or a new air conditioner should be selected based on your home's true heating and cooling needs—not just square footage or the size of the previous unit.
That's why reputable contractors conduct an HVAC load calculation, also called a Manual J calculation, before recommending replacement equipment. A Manual J calculation considers many details that affect your home's comfort needs, including:
- Home square footage
- Room height
- Window size and direction
- Insulation
- Air infiltration
- Local climate
- Household occupants
- Heat generated by appliances and lighting
- Ductwork condition
A properly sized air conditioner runs for enough time to cool your home consistently while pulling out excess humidity. That means more even temperatures, better indoor comfort and improved humidity control. Proper sizing also helps the equipment to run more effciently, reducing unnecessary wear that can shorten its lifespan or lead to costly breakdowns.
When your heating or cooling system is properly sized, you get greater comfort and long-lasting performance.
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 often isn't a smart choice.
heating and cooling systems that are bigger than necessary or smaller than your home requires can create comfort problems, 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 cycles repeatedly, reducing efficiency and increasing wear.
- High indoor humidity: Oversized air conditioners finish cooling cycles too soon to remove excess moisture from the air.
- Uneven temperatures: Some rooms feel too cool while others stay too warm.
- 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.
Cons Associated with 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 thermostat setting, which also causes additional wear.
- Difficulty maintaining the desired temperature: 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 for extended periods can increase utility bills.
- Extra stress during severe weather: HVAC systems that are too small can run extremely hard in extreme temperatures, increasing component strain and the likelihood of repairs.
Why You Should Balance HVAC System Efficiency and Size
When trying to decide between a high SEER vs right-sized system, keep in mind that you don't necessarily need the top-efficiency model on the market.
More often than not, a professionally sized, mid-efficiency HVAC system will deliver better performance than an oversized premium system because it runs the way it was designed to.
Thesmartest choice is an energy-efficient HVAC system that's matched for your home, your budget, your climate and your long-term needs.
As you consider how to choose a new air conditioner or furnace, keep these factors in mind:
- Lower energy costs: Higher-efficiency and right-sized systems can decrease electricity use.
- Purchase price: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can lower long-term energy costs.
- Energy prices: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's crucial your heating or cooling system has enough capacity to handle areas with extremely cold winters or extremely hot summers.
- Length of home ownership: If you plan to stay in your home for many years, the long-term energy savings of a higher-efficiency unit may be worth the investment.
- Financial incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can lower the overall cost of higher-efficiency systems.
Real-World Comparison: High Seer vs. Right System Size
How does this work in a real world example?
Suppose there are two neighboring homes.
In one, 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. At the neighboring home, an HVAC professional installs a right-sized, mid-efficiency system after completing a Manual J calculation.
Even though the second system has a lower efficiency rating on paper, it may deliver lower operating costs, better home comfort, improved humidity control and last longer because it's correctly matched to the home's needs.
Work With an HVAC Professional Who Designs Solutions Tailored to Your Home
Replacing your HVAC system should involve much more than selecting a system with the top efficiency rating. An ideal system is one that meets your household heating and cooling requirements.
At Ambience HVAC, Inc., our knowledgeable technicians perform an HVAC load calculation. We'll carefully evaluate your home's layout and construction, your household's comfort needs and recommend equipment that's designed specifically for your home—not simply the largest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will help you identify any available rebates or tax incentives and provide information about HVAC financing options that make energy-efficient HVAC systems more accessible for all budgets.
Schedule an HVAC consultation online with Ambience HVAC, Inc. to get started. We'll evaluate your home, answer your questions and help you choose the properly sized high-efficiency system that keeps your family comfortable for many years.