Should I repair or replace my air conditioner?

By Dana Whitlock. Updated October 13, 2026. How we work.

Cheap parts and the sealed system

Most AC breakdowns on a 95-degree afternoon come down to a small part. Capacitors, contactors, fan motors, relays and thermostats fail often, especially in heat waves, and each costs a sliver of what a new system does. Fix them, unless the system is very old.

The other group is the sealed refrigerant system: the compressor, the outdoor condenser coil, the indoor evaporator coil and the copper lines between them. Repairs there are expensive and labor-heavy, and on older equipment they collide with refrigerant rules. Nearly every hard repair-or-replace call lives in this group.

When fixing it makes sense

Lean toward repair when the system has plenty of years left and the sealed system is untouched. A sealed-system failure can still make sense to fix when the part is under warranty.

• A capacitor, contactor or condenser fan motor failure on a system of any reasonable age.
• A clogged condensate drain, or a coil that froze because the filter was filthy.
• One findable refrigerant leak on a system under about 10 years old.
• A compressor or coil failure still covered by the manufacturer's parts warranty.
• Thermostat or low-voltage wiring problems.

When a new system makes sense

Lean toward replacement when the sealed system fails on an older unit, when leaks keep coming back, or when the system runs on a refrigerant no longer allowed in new equipment.

• Compressor failure out of warranty on a system past about 10 to 12 years.
• An evaporator coil with pinhole leaks. ACHR News describes formicary corrosion, in which acids from household chemicals eat through copper coils, as hard to locate and prone to recurring.
• A system that has needed refrigerant added more than once.
• Any major sealed-system repair on an R-22 system.
• A system that can't keep the house comfortable on hot days even when it's working right.

How refrigerant rules change the decision

Most systems installed before about 2010 run on R-22, which is being phased out under the Clean Air Act. Federal rules at 40 CFR 82.15 have barred using R-22 in newly manufactured equipment since January 1, 2010, and allow continued use of used, recovered and recycled R-22 for existing equipment. So an R-22 system can still be serviced, from a shrinking supply. Sinking a large share of a new system's price into an R-22 compressor or coil is rarely good value.

Systems installed in roughly 2010 through 2024 mostly use R-410A. EPA's HFC rule at 40 CFR 84.54 restricts installing new residential air conditioning systems that use refrigerants with a global warming potential of 700 or higher, effective January 1, 2025, with a limited allowance for systems built entirely from components manufactured before that date. New equipment now uses lower-GWP refrigerants, mostly the mildly flammable A2L types such as R-454B and R-32. Technicians can still repair existing R-410A systems.

The pinch comes with partial replacement. A new outdoor unit designed for an A2L refrigerant generally needs a matching indoor coil and often new line sets or fittings, so swapping just the condenser on an older R-410A system is harder than it used to be. When a contractor proposes replacing one half of a split system, ask what refrigerant each piece uses and whether the pair is a manufacturer-matched system.

Doing the arithmetic

Divide the repair cost by the years the system can realistically keep running. Divide the replacement cost shown above by the years a new system should last. Compare.

Say a 6-year-old system in a northern state needs a new condenser fan motor, quoted at about 5 percent of the replacement figure for your area. DOE's analysis puts split-system AC life at about 24 years in the North, so even a conservative 15-year expectation leaves around 9 more years. Five percent over 9 years is roughly half a percent per year. A new system over 15 to 20 years runs 5 to 7 percent per year. Repair.

Now a 13-year-old system in a hot-humid area with a failed compressor, out of warranty, quoted at about 40 percent of a new system. DOE's hot-humid average is about 18 years, so maybe 4 or 5 more years if nothing else gives out. Forty percent over 4.5 years is close to 9 percent per year, well above the 6 or so percent a new system costs. Replace. You also get a current refrigerant and a new coil.

The calculator on this page runs the same comparison with your numbers.

Where the 50 percent rule fits for AC

The old shortcut says to replace when a repair costs more than half the price of a new system. Past about 10 years, it agrees with the cost-per-year math most of the time. On a younger system it can steer you wrong. A warranty-covered compressor may leave only labor and refrigerant on the bill, so a scary quote can shrink a lot.

Other things that move the line

Climate and age. DOE's lifetime estimates for split-system central air conditioners are about 24.1 years in the North, 24.9 years in the hot-dry region and 18.0 years in the hot-humid region. Builder and inspector charts are more cautious, mostly landing between 7 and 15 years, with condensers up to 20. Coastal and Gulf systems tend to give out sooner.

Efficiency standards. Federal minimum efficiency standards for central air conditioners changed on January 1, 2023, and are now rated in SEER2. A mid-2000s system is far less efficient than anything on the market now, so in hot places with long cooling seasons the energy savings pull the replacement date earlier.

Warranty. Check whether the compressor and coil are still covered and whether the system was registered. Parts coverage commonly excludes labor and refrigerant, and on a compressor job those are a big slice of the bill.

The furnace or air handler. Your indoor coil sits on the furnace or inside an air handler, and the blower pushing your cool air belongs to that unit. If the furnace is also near the end, replacing both at once means paying once for removal, matching and setup.

Safety. Electrical parts in the outdoor unit store high voltage, and A2L refrigerants are mildly flammable. Diagnosis and repair belong to a licensed HVAC technician. Your part is the thermostat, the filter, one breaker reset, and clearing leaves and grass clippings away from the outdoor unit.