Shopping for a new air conditioning system or furnace can be intimidating. If you're trying 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 equipment should deliver the most comfort and lowest energy bills, right?
It’s not quite that simple.
Energy efficiency isn't the only thing you should consider when it comes to new air conditioner installation or replacing your furnace. Although many people 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 has a major impact on humidity control and system longevity. The best HVAC system for your home combines efficiency and correct sizing.
In thisguide, 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 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), shows how efficiently an air conditioner cools your home over a normal cooling season. A SEER2 rating is the newer version of SEER, using testing methods that better represent real-world operating conditions. Most new air conditioners have a SEER2 efficiency rating, simply because this rating is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is measured by something called AFUE, which is for Annual Fuel Utilization Efficiency. Like cooling efficiency ratings, higher AFUE ratings indicate a high-efficiency HVAC system that uses less electricity to heat your home than lower-rated systems under standardized laboratory testing.
Even so, high numbers don't automatically guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on more than just efficiency ratings, including the way the system is installed, the state of your ductwork, your home's insulation, thermostat settings and, most importantly, system sizing. Even the highest-rated system cannot perform as intended if it is bigger than necessary or too small for the home.
Why HVAC System Size Matters More Than You Probably Think
Many assume a bigger air conditioner or furnace will heat or cool a home better or that they should simply replace their old HVAC system with a unit of the same capacity. The truth is, new heating system installation or a new air conditioner should be chosen based on your home's current heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable technicians perform an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation analyzes many factors that affect your home's heating and cooling requirements, including:
- Home square footage
- Room height
- Window size and orientation
- Home insultation levels
- Air leakage
- Local climate
- Number of occupants
- Heat produced from appliances and lighting
- Air duct condition
A properly sized air conditioner runs for enough time to cool your home more uniformly while pulling out excess humidity. That means more even temperatures, better indoor comfort and improved indoor humidity management. This also allows the equipment to run more effciently, reducing strain that can reduce its service life or lead to costly breakdowns.
When HVAC equipment is properly sized, you get improved comfort and more dependable performance.
Problems with Oversized and Undersized Heating and Cooling Systems
You may be tempted to buy the most energy efficient, largest-capacity air conditioner or heating system on the market. In reality, that's usually not a smart choice.
heating and cooling systems that are bigger than your home needs or smaller than your home requires can create comfort problems, increase utility costs and reduce efficiency regardless of their SEER rating.
Drawbacks of Oversized HVAC Systems
An oversized air conditioner or heating system may reach the thermostat setting fast, but that doesn't mean it delivers the best comfort.
- Short cycling: An oversized HVAC system cycles repeatedly, reducing efficiency and increasing wear.
- Humidity problems: Oversized air conditioners cool your home too quickly to remove indoor humidity from the air.
- Hot and cold spots: Some rooms get too cold while others aren’t ever cool enough.
- Increased wear and tear: Even though the system works quickly, those repeated on-and-off cycles can cause avoidable breakdowns due to the strain.
Issues Created by Undersized HVAC Systems
An undersized HVAC system also can struggle:
- Continuous operation: The system operates almost continuously 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 energy costs.
- Greater strain on very hot or cold days: HVAC systems that are too small can work harder in extreme temperatures, increasing wear and the risk of breakdowns.
Why You Should Balance HVAC System Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, keep in mind that you don't automatically need the most efficient model on the market.
More often than not, a correctly sized, mid-efficiency HVAC system will provide better results than an overly large premium system because it operates 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 long-term goals.
When deciding how to choose a new air conditioner or furnace, consider:
- Efficiency savings: Higher-efficiency and right-sized systems can decrease 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.
- Local utility costs: Areas with more expensive electricity may see better long-term savings from higher-efficiency units.
- Climate: It's essential your heating or cooling system has adequate capacity to handle areas with extremely cold winters or very hot summers.
- Time you plan to own the home: If you intend to remain in your home for many years, the long-term energy savings of a higher-efficiency unit may offset the investment.
- Available rebates or tax 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?
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 simply matched the previous unit. The other homeowner installs a properly sized, mid-efficiency system after completing a Manual J calculation.
While 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 have a longer lifespan because it's appropriately sized to the home's needs.
Choose the HVAC Professional Who Designs Solutions Tailored to Your Home
HVAC replacent or installation should involve more than selecting a model with the highest efficiency rating. An ideal system is one that meets your home’s heating and cooling requirements.
At Dave's Diversified Services, our knowledgeable technicians perform an HVAC load calculation. We'll 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, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our heating and cooling specialists will help you identify 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 Dave's Diversified Services now. Our team will evaluate your home, answer any questions and help you choose the right-sized high-efficiency system that keeps your family comfortable for many years.