Choosing a new air conditioning system or furnace can be intimidating. When you're looking to find the best HVAC system for your home, it's natural to look for models with the highest efficiency ratings.
Surely the most efficient system provides 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 furnace replacement. Even though many 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 power bills.
Proper sizing also influences humidity control and lasting performance. The best HVAC system for your home combines efficiency and proper sizing.
In thisarticle, 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 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 effectively a cooling system cools your home over a normal cooling season. A SEER2 rating is the current version of SEER, using testing methods that better reflect real-world operating conditions. Most new air conditioners have a SEER2 designation, simply because this rating is the current rating system for cooling equipment.
Fuel-burning heating system efficiency is evaluated by something called AFUE, which is short for Annual Fuel Utilization Efficiency. Like SEER and SEER2 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.
That said, high ratings don't by themselves guarantee lower utility bills. Everyday heating and air conditioner efficiency depends on many factors, including the installation quality, the state of your ductwork, how much insulation your home has, thermostat settings and, most importantly, proper HVAC system sizing. Even the highest-efficiency system cannot deliver peak performance if it is bigger than necessary or smaller than needed for the home.
Why HVAC System Size Matters More Than You Probably Think
Many assume a larger air conditioner or furnace will heat or cool a home better or that they should just replace their old HVAC system with a new one the same size. Actually, new heating system installation or air conditioner replacement should be sized based on your home's actual heating and cooling needs—not just square footage or the capacity of the old system.
That's why reputable contractors conduct an HVAC load calculation, also called a Manual J calculation, before suggesting replacement equipment. A Manual J calculation analyzes many factors that impact your home's comfort needs, including:
- Home square footage
- Ceiling height
- Window size and placement
- Home insultation levels
- Air leakage
- Local climate
- Household occupants
- Heat produced from 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 steadier temperatures, better indoor comfort and improved indoor humidity management. Proper sizing also helps the equipment to operate more effciently, reducing strain that can shorten its lifespan or lead to frequent or expensive repairs.
When HVAC equipment is properly sized, you get improved comfort and more reliable operation.
Problems Caused by Oversized and Undersized Heating and Cooling Systems
Many homeowners are tempted to buy the most energy efficient, biggest air conditioner or heating system on the market. The truth is, that’s rarely a smart choice.
heating and cooling systems that are bigger than necessary or too small 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 starts and stops often, reducing efficiency and increasing wear and tear.
- Reduced humidity control: Oversized air conditioners cool your home too quickly to remove excess moisture from the air.
- Inconsistent temperatures: Some rooms become too cold while others never feel comfortable.
- Additional equipment wear: 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 has a different set of problems:
- Long run times: The system runs for long periods trying to reach the desired temperature, which also causes extra strain.
- Difficulty reaching thermostat settings: Your home may not feel comfortable during hot weather or feel too cool during winter.
- Higher energy use: Running almost constantly can increase utility bills.
- Extra stress during severe weather: HVAC systems that are too small can struggle in extreme temperatures, increasing component strain and the likelihood of repairs.
Finding the Right Balance Between Efficiency and Size
When weighing the pros and cons of a high SEER vs right-sized system, keep in mind that you don't necessarily need the top-efficiency model on the market.
Often, a professionally sized, mid-efficiency HVAC system will outperform an oversized premium system because it functions 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.
As you consider how to choose a new air conditioner or furnace, think about:
- Energy savings: Higher-efficiency and right-sized systems can reduce electricity use.
- Initial cost: High-efficiency AC and heating systems often cost more initially than mid-range models but can lower long-term energy costs.
- Local utility costs: Areas with higher utility costs may see more significant long-term savings from higher-efficiency units.
- Seasonal weather conditions: It's essential your heating or cooling system has the right capacity to handle areas with harsh winter weather or very 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 justify the investment.
- Available rebates or tax incentives: Manufacturer promotions, {utility|equipment rebates and tax credits can reduce the overall cost of higher-efficiency systems.
Real-World Example: High Seer vs. Right System Size
How does this work in the real world?
Suppose there are two neighboring homes.
At the first home, 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 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 properly matched 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. An ideal system is one that meets your heating and cooling requirements.
At Jack's Heating, Cooling, Stoves & Fireplaces, our skilled HVAC experts perform an HVAC load calculation. We'll evaluate your home's design, your household's comfort goals and recommend equipment that's properly matched for your home—not simply the largest, fanciest 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 efficient heating and cooling systems more accessible for all budgets.
Schedule an HVAC consultation online with Jack's Heating, Cooling, Stoves & Fireplaces now. We'll gladly evaluate your home, answer any questions and help you choose the properly sized efficient system that keeps your family comfortable for the long haul.