When it comes time to have your air conditioner replaced, one of the first questions you’ll surely have is how much the replacement will cost. The average cost to replace just the outdoor AC unit is around $6,000, but the price could be as low as $4,000 or as high as $15,000 to $20,000. The reason that the price can vary so much is that it depends on the size of your home; what type, brand, and model of new unit you choose; and how energy efficient the unit is.

It also depends on whether you only need to replace the outdoor AC unit itself or some of the system’s other components, such as the evaporator coil and blower. If your current system is more than 10 to 15 years old, it’s generally best to replace all of the components. In this case, you’re usually looking at spending at least a few thousand dollars more. A new blower will usually run about $500, and you should expect to pay around $2,000 to have a new evaporator coil installed.

The fact that the price to replace an AC system can vary so much means it is important that you choose a knowledgeable, reputable HVAC contractor to make sure the job is done right and that you’re getting a good deal. In addition, only a certified HVAC technician will really be able to tell you what size of unit you need. This will ensure you don’t waste your money on an AC that is too small or too large for your home. Let’s take a look at the factors that can help determine what size of AC you need and also some of the other factors that can affect the cost of your replacement unit.

How Home Size and Climate Determine AC Size

Two of the biggest factors that will determine how much your replacement AC unit costs are the size of your home and what type of climate you live in. The climate zone determines how many BTUs of cooling per square foot you need, and the size of your home determines how many total BTUs the unit needs to produce to cool your home efficiently.

The Atlanta area is in U.S. Climate Zone 3. In this zone, the general recommendation is that you need an AC unit that produces somewhere between 30 and 45 BTUs per square foot. This means you will usually need around 60,000 to 90,000 BTUs to cool a 2,000-square-foot home.

Central AC units are measured in tons, and each ton is equal to 12,000 BTUs. This means that for a 2,000-square-foot home, you would usually need somewhere between 5 and 7.5 AC tons. However, the largest residential AC unit on the market is only 5 tons, which means you may need to use two separate units.

Insulation and Air Sealing

How well-insulated your home is and how many gaps it has in the exterior structure are also hugely important in determining what size of AC unit you need and thus how much you can expect your new unit to cost. If you have a newer home that is sufficiently insulated and has a well-sealed exterior envelope, you may only need 20 to 25 BTUs per square foot. If your home is poorly insulated and has lots of air leaks, you will need a much larger AC unit as this will lead your home to experience far greater heat gain.

Understanding Manual J Load Calculations

Professional HVAC technicians always use a formula known as a Manual J calculation when sizing AC units. This formula still takes into account the total square footage of the home, the climate, and the level of insulation, but it also factors in many other important details that can increase or decrease how many BTUs are needed.

The formula generally factors in an additional 500 BTUs for every person living in the home and 1,000 extra BTUs for every exterior door and window. The location of all the windows in the home is also important since this will determine how much heat gain the home gets from the sun. This is why the Manual J calculation also looks at how much direct sunlight or shade the home gets during the day.

Having a Manual J calculation performed is essential for ensuring that your new unit is the right size for your home. Once you know what size unit you need, you can then start estimating costs based on the type of unit you choose and its energy efficiency rating.

Understanding SEER Ratings

The energy efficiency of central air conditioners is calculated using the Seasonal Energy Efficiency Ratio or SEER scale. The minimum rating required by federal law in Georgia is 15 SEER. A 15 SEER unit will always be the cheapest option, but it will also use more energy than a higher-rated unit. If you were to opt for a unit that was rated at 20 SEER or higher, you should expect to pay at least a few thousand dollars more than you would for a basic 15 SEER unit. Nonetheless, a higher SEER unit is still often the most cost-effective option in the long run due to the increased energy savings. This factor is definitely something to take into account when choosing what model of new AC unit you want.

Single-Stage vs. Two-Stage and Variable-Speed ACs

The type of unit you choose will also dictate how much it costs. Single-stage ACs are the most basic type of unit and thus the least expensive. However, they are also the least energy efficient as they always have to run at full power no matter what the temperature is or how much cooling is currently required.

Two-stage AC units are more expensive but will save you quite a bit of money in the long run. A two-stage unit always turns on at low power and will only run on full power on much hotter, more humid days or when your home’s temperature is much higher than the thermostat setting. The fact that the unit can run at low power also means it will usually be much quieter than a single-stage AC.

Variable-speed ACs are the most efficient and thus the most expensive option. These units typically have at least five different power settings so they can better adjust their performance and energy usage based on the current cooling requirements. If you’re looking to upgrade from a single-speed or two-speed unit to a variable-speed AC, you will also need to figure in the cost of having a new blower installed inside your home. This is because variable-speed units require a variable-speed blower whereas the other units have a standard single-speed blower.

As you can see, there are a number of different factors that can determine how much you should expect to pay for an AC replacement. At Bardi Heating, Cooling & Plumbing, we pride ourselves on being honest and upfront about all the work we perform, which is why we will always provide a full cost estimate for your AC replacement before we get started. Our team will also calculate exactly what size of unit you need and help you choose which model best meets your budget and your needs. If you’re in need of AC replacement, HVAC, or plumbing services in Norcross, give us a call today.

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