Choosing a new air conditioner or furnace can be stressful. When you're looking to find the best HVAC system for your home, it's common to focus on models with the highest efficiency ratings.
Surely the most efficient equipment provides the most comfort and lowest energy bills, right?
Actually, that’s not always the case.
High efficiency isn't the only thing to think about when it comes to new air conditioner installation or installing a new furnace. While many homeowners focus only on {energy efficiency|efficiency ratings, proper {HVAC system sizing is equally, if not more important for your home's comfort and your energy bills.
Proper sizing has a major impact on humidity control and lasting performance. The best HVAC system for your home balances efficiency and correct sizing.
In thisarticle, we'll explain what an air conditioner's SEER rating or SEER2 rating actually measures, why correct HVAC size is so important and why trusted HVAC experts consider both when recommending 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), measures how effectively 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 simulate real-world operating conditions. Today’s new air conditioners have a SEER2 designation, 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 for Annual Fuel Utilization Efficiency. Similar to 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 ratings don't necessarily guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on more than just efficiency ratings, including the quality of the installation, the condition of your ductwork, your home's insulation, thermostat settings and, most importantly, proper HVAC system sizing. Even the highest-efficiency system cannot perform as intended if it is oversized or smaller than needed for the home.
Why Proper HVAC Sizing Matters More Than You Think
Many assume a larger 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 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 evaluates many details that affect your home's heating and cooling load, including:
- Total square footage
- Room height
- Window size and placement
- Home insultation levels
- Air leakage
- Regional climate
- Household occupants
- Heat generated by appliances and lighting
- Air duct condition
A properly sized air conditioner runs through longer cooling cycles 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 run more effciently, reducing excessive wear and tear that can cause it to wear it out sooner or lead to costly breakdowns.
When HVAC equipment is the right size for your home, you get improved comfort and more reliable operation.
Problems Caused by Oversized and Undersized HVAC Equipment
You may be tempted to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. However, that's usually not a great idea.
HVAC systems that are too large or undersized can create comfort issues, increase operating 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 performs efficiently.
- Short cycling: An oversized HVAC system turns on and off frequently, reducing efficiency and increasing wear and tear.
- Poor humidity removal: Oversized air conditioners finish cooling cycles too soon to remove indoor humidity from the air.
- Inconsistent temperatures: Some rooms get too cold while others aren’t ever cool enough.
- More wear and tear: Even though the system heats or cools your home fast, those frequent starts and stops 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 runs for long periods trying to reach the desired temperature, which also causes extra strain.
- Difficulty maintaining the desired temperature: Your home may feel cool enough during hot weather or never feel warm enough in cold weather.
- Greater energy usage: Running almost constantly can increase utility bills.
- 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.
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 most efficient model on the market.
In many cases, a correctly sized, mid-efficiency HVAC system will outperform an overly large premium system because it functions the way it was designed to.
Thebest 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:
- Energy savings: 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 more significant long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's crucial your heating or cooling system has adequate capacity to handle areas with very cold winters or intense summer heat.
- How long you'll 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 justify the investment.
- Financial incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can offset the overall cost of qualifying equipment.
Real-World Situation: High Seer vs. Right System Size
How does this play out in a real world scenario?
Picture two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system that's too big because the contractor only matched the previous unit. At the neighboring home, an HVAC professional installs a right-sized, moderate-efficiency system after completing a Manual J calculation.
Even though the second system has a more modest efficiency rating on paper, it may provide lower operating costs, better home comfort, more effective humidity control and last longer because it's appropriately sized to the home's needs.
Choose the HVAC Professional Who Designs Personalized Solutions
HVAC replacent or installation should involve more than selecting a system with the highest efficiency rating. The best system is one that meets your home’s heating and cooling requirements.
At Western Mechanical, Inc., our skilled HVAC experts perform an HVAC load calculation. Our team will evaluate your home's layout and construction, your household's comfort goals and recommend equipment that's right for your home—not simply the biggest, latest and greatest unit or the one with the highest AFUE or SEER2 rating.
Our team will connect you with 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 Western Mechanical, Inc. today. We'll gladly evaluate your home, answer your questions and help you choose the correctly sized high-efficiency system that keeps your family comfortable for the long haul.