Choosing a new air conditioner or furnace can be intimidating. When you're looking to find the best HVAC system for your home, it's natural to focus on models with extremely high 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 you should consider when it comes to new air conditioner installation or furnace replacement. 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 energy bills.
Proper sizing has a major impact on humidity control and system longevity. The best HVAC system for your home delivers energy efficiency and proper sizing.
In thisblog, 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 experienced HVAC professionals consider both when helping you choose 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 effectively a cooling system cools your home over a normal cooling season. A SEER2 rating is the current version of SEER, using evaluation methods that better represent real-world operating conditions. Nearly all new air conditioners have a SEER2 rating, simply because this is the updated rating system for cooling equipment.
Fuel-burning heating system efficiency is rated by AFUE, which is for Annual Fuel Utilization Efficiency. As with 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.
However, high numbers don't necessarily guarantee lower utility bills. Actual heating and air conditioner efficiency depends on many factors, including the installation quality, the quality of your ductwork, how much insulation your home has, thermostat settings and, most importantly, HVAC system sizing. Even the most efficient system cannot operate at its best if it is oversized or undersized for the home.
Why HVAC System Size Matters More Than You Think
Many assume a larger air conditioner or furnace will make their home the most comfortable or that they should just replace their old HVAC system with a new one the same size. The truth is, new heating system installation or AC replacement should be selected 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 companies complete an HVAC load calculation, also called a Manual J calculation, before selecting replacement equipment. A Manual J calculation analyzes many variables that affect your home's heating and cooling load, including:
- Overall square footage
- Room height
- Window size and placement
- Home insultation levels
- Drafts and air leakage
- Regional climate
- Household occupants
- Heat produced from appliances and lighting
- Air duct condition
A properly sized air conditioner runs for enough time to cool your home consistently while removing excess humidity. That means more consistent temperatures, better indoor comfort and improved indoor humidity management. This also allows the equipment to run more effciently, reducing excessive wear and tear that can shorten its lifespan or lead to more repairs and higher repair costs.
When HVAC equipment is properly sized, you get improved comfort and long-lasting performance.
Problems with Oversized and Undersized HVAC Equipment
Many homeowners are tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. However, that's usually not a smart choice.
heating and cooling systems that are bigger than your home needs or undersized can create comfort issues, increase operating costs and reduce efficiency regardless of their SEER rating.
Issues Created by 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 reach the set temperature too fast to remove excess moisture from the air.
- Uneven temperatures: Some rooms get too cold while others never feel comfortable.
- Additional equipment wear: Even though the system reaches the target temperature rapidly, those frequent starts and stops can cause avoidable breakdowns due to the strain.
Drawbacks of Undersized HVAC Systems
An undersized HVAC system has a different set of problems:
- Long run times: The system runs for long periods trying to reach the set temperature, which also causes extra strain.
- Trouble reaching the thermostat setting: Your home may feel cool enough during hot weather or always feel chilly in the winter.
- Greater energy usage: Running for extended periods can increase energy costs.
- Extra stress during severe weather: HVAC systems that are too small can work harder in extreme temperatures, increasing wear and the chance of failure.
Finding the Right Balance Between Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, remember that you don't always need the most efficient model on the market.
In many cases, a professionally sized, mid-efficiency HVAC system will outperform an oversized 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 future plans.
When deciding how to choose a new air conditioner or furnace, consider:
- Energy savings: Higher-efficiency and right-sized systems can decrease electricity use.
- Upfront investment: High-efficiency AC and heating systems often require a larger upfront investment than mid-range models but can help reduce long-term energy costs.
- Energy prices: Areas with higher utility costs may see greater long-term savings from higher-efficiency units.
- Climate: It's crucial your heating or cooling system has the right capacity to handle areas with very cold winters or very hot summers.
- Time you plan to own the home: If you plan to stay 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 reduce the overall cost of high-efficiency HVAC equipment.
Real-World Example: High Seer vs. Right System Size
How does this work in a real world scenario?
Imagine two neighboring homes.
In one, the homeowner chooses a premium high-efficiency HVAC system has far more capacity than the home needs because the contractor replaced it with the same size system as the previous unit. At the neighboring home, an HVAC professional installs a correctly 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, improved humidity control and have a longer lifespan because it's correctly matched to the home's needs.
Choose the HVAC Professional Who Designs the Right Solution
HVAC replacent or installation should involve more than selecting a system with the highest efficiency rating. An ideal system is one that meets your home’s heating and cooling requirements.
At Mountain Air, our skilled HVAC experts 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 properly matched for your home—not simply the highest-capacity, most expensive unit or the one with the highest AFUE or SEER2 rating.
Our team will help you identify any available rebates and 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 Mountain Air now. We'll evaluate your home, answer any questions and help you choose the right-sized efficient system that keeps your family comfortable for years to come.