How Much Does a New AC Unit Cost?

A new central air conditioner costs $4,500 to $8,500 installed in the Springfield area, with most three-ton residential replacements landing between $5,500 and $7,000. Larger four and five-ton systems run $6,500 to $9,500, and high-efficiency variable-speed equipment reaches $8,000 to $12,500. Those figures are for a complete installed system, not equipment alone, which is the number that actually matters to you.

Be careful comparing quotes that are not quoting the same job. An outdoor condenser by itself might be $1,800 to $3,500, and a quote built around that figure is either omitting the indoor evaporator coil or assuming your existing one is compatible. Mismatched coils are a real problem: the system will run, but it will not hit its rated efficiency and the compressor works harder than designed. Any quote worth comparing includes the condenser, a matched indoor coil, refrigerant line evaluation, electrical connection, disposal of the old equipment, and full commissioning.

Tonnage is the largest single price driver and it should come from a load calculation, not from square footage. The old rule of one ton per 500 square feet ignores insulation, window area and orientation, air sealing and duct condition. Oversizing is the more common error and it produces a specific complaint here: the system cools the air quickly, satisfies the thermostat, shuts off before it has removed much moisture, and leaves a Springfield August feeling cool but clammy. Longer runs at lower output are what actually dehumidify.

Efficiency rating moves the price next. SEER2 is the current standard, with baseline equipment around 14 and high-efficiency units into the low 20s. Each step up costs more upfront and less to run, but the payback depends heavily on how many cooling hours you actually accumulate. Springfield gives roughly three to four months of meaningful cooling load, which is far less than a Gulf Coast climate, so payback on the highest tiers stretches long. The better argument for premium equipment here is comfort rather than economics, since variable-speed systems control humidity considerably better.

Ductwork is the variable that surprises people. If your existing ducts are sound and correctly sized, the new system connects to them and nothing changes. If they leak significantly, are undersized for the new equipment, or have runs that have come loose in the crawlspace, connecting new equipment to them wastes a good part of what you just spent. Duct sealing typically adds $600 to $1,800 and is frequently the difference between a system that performs as specified and one that disappoints.

On repair versus replacement, the practical framework is age against repair cost. Under about ten years with a repair under $1,000, repair almost always wins. Over fifteen years with a failed compressor, replacement almost always wins, because a compressor replacement on an old unit costs a substantial fraction of a new system while leaving every other aging component in place. Between those two, weigh the repair against the remaining life and factor in whether you are on R-22.

R-22 deserves its own paragraph. Systems using R-22 refrigerant, generally installed before 2010, face a supply that has been phased down until the cost per pound is now high enough that a single significant recharge can approach a meaningful share of a replacement. If your system is R-22 and it has a leak, the arithmetic almost always favors replacement even if the unit is otherwise functional.

Replacing the furnace at the same time is worth pricing rather than dismissing. A combined AC and furnace replacement runs $9,000 to $16,000, which is less than the two jobs done separately because the labor happens once. If your furnace is a similar age to your condenser, doing both together avoids paying a second crew to open the same cabinet in two years, and it ensures the blower is properly matched to the new outdoor equipment. Our AC installation and furnace installation pages break down each side.