Shopping for a new air conditioning system or furnace can be stressful. When you're looking to find the best HVAC system for your home, it's understandable to look for models with the highest efficiency ratings.
After all, the most efficient equipment should deliver the most comfort and lowest energy bills, right?
It’s not quite that simple.
Efficiency ratings aren’t the only thing you should consider when it comes to new air conditioner installation or installing a new furnace. Even though many focus only on {energy efficiency|efficiency ratings, proper {HVAC system sizing is equally, if not more important for your home's comfort and your power bills.
Proper sizing directly impacts humidity control and system longevity. 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 experienced HVAC professionals 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 AC cools your home over a typical cooling season. A SEER2 rating is the updated 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 is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by 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 achieve indoor comfort than lower-rated systems under standardized laboratory testing.
However, high ratings don't necessarily guarantee lower utility bills. Actual heating and air conditioner efficiency depends on several key factors, including the installation quality, the quality of your ductwork, insulation levels, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot perform as intended if it is bigger than necessary or too small for the home.
Why HVAC System Size Matters More Than Most Homeowners Realize
Many assume a higher-capacity air conditioner or furnace will work the best or that they should just replace their old HVAC system with a unit of the same capacity. Actually, new heating system installation or a new air conditioner should be sized 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 contractors complete an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation considers many factors that affect your home's heating and cooling load, including:
- Total square footage
- Ceiling height
- Window size and placement
- Insulation
- Air infiltration
- Local climate
- Household occupants
- Heat produced from appliances and lighting
- Air duct condition
A properly sized air conditioner runs long enough to cool your home consistently while removing excess humidity. That means steadier temperatures, better indoor comfort and improved moisture control. This also allows the equipment to run more effciently, reducing strain that can shorten its lifespan or lead to frequent or expensive repairs.
When your heating or cooling system is correctly sized, you get greater comfort and more dependable performance.
Problems with Oversized and Undersized HVAC Equipment
Many homeowners are tempted to buy the most energy efficient, highest-capacity air conditioner or heating system on the market. However, that often isn't a smart choice.
HVAC systems that are bigger than your home needs or too small can create indoor comfort challenges, increase utility costs and reduce efficiency regardless of their SEER rating.
Drawbacks of Oversized HVAC Systems
An oversized air conditioner or heating system may heat or cool rapidly, but that doesn't mean it delivers the best comfort.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing equipment strain.
- Reduced humidity control: Oversized air conditioners reach the set temperature too fast to remove enough moisture from the air.
- Uneven temperatures: Some rooms feel too cool while others stay too warm.
- More 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 can have the opposite problem:
- Long run times: The system stays on for extended periods trying to reach the set temperature, which also causes extra strain.
- Trouble reaching the thermostat setting: Your home may never feel as cool as you want during hot weather or never feel warm enough in cold weather.
- Higher energy use: Running for extended periods can increase energy costs.
- Added strain during extreme weather: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the risk of breakdowns.
Why You Should Balance HVAC System Efficiency and Size
When trying to decide between a high SEER vs right-sized system, don't forget that you don't necessarily need the top-efficiency model on the market.
In many cases, 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 future plans.
As you think about how to choose a new air conditioner or furnace, keep these factors in mind:
- Lower energy costs: Higher-efficiency and right-sized systems can reduce electricity use.
- Upfront investment: High-efficiency AC and heating systems often have a higher purchase price than mid-range models but can help reduce long-term energy costs.
- Energy prices: Areas with more expensive electricity may see more significant long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's essential your heating or cooling system has enough capacity to handle areas with very cold winters or extremely hot summers.
- Time you plan to own the home: 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.
- Rebates and tax credits: 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 work in a real world example?
Picture two neighboring homes.
In the first, 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. Next door, the second homeowner installs a right-sized, moderate-efficiency system after completing a Manual J calculation.
Although 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 properly matched to the home's needs.
Work With an 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. The right system is one that meets your home’s heating and cooling requirements.
At Polar Air & Mechanical, our knowledgeable technicians perform an HVAC load calculation. We'll carefully evaluate your home's layout and construction, your household's heating and cooling preferences 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 HVAC experts will let you know about any available tax rebates and provide information about HVAC financing options that make high-efficiency systems more accessible for all budgets.
Schedule an HVAC consultation online with Polar Air & Mechanical today. We'll 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.
