The average AC replacement costs $5,500 to $12,500 for the condenser unit and installation. A complete AC + furnace system runs $7,500 to $15,500.
Air conditioner replacement cost depends on the size of your home, the efficiency rating you choose, and the complexity of the installation. The condenser unit itself typically costs $2,500 to $6,000, with installation labor adding another $2,000 to $4,000.
If your furnace or air handler is also aging, most contractors recommend replacing both at the same time. Mismatched systems can reduce efficiency by 10–15% and may void manufacturer warranties.
| AC Size | Home Size | AC Only | AC + Furnace |
|---|---|---|---|
| 2 Ton | 800–1,200 sq ft | $5,000–$7,500 | $7,500–$10,500 |
| 2.5 Ton | 1,200–1,500 sq ft | $5,500–$8,000 | $8,000–$11,500 |
| 3 Ton | 1,500–2,000 sq ft | $6,000–$9,000 | $8,500–$13,000 |
| 3.5 Ton | 2,000–2,600 sq ft | $6,500–$10,000 | $9,500–$14,500 |
| 4 Ton | 2,600–3,200 sq ft | $7,500–$11,000 | $10,500–$16,000 |
| 5 Ton | 3,200+ sq ft | $8,500–$12,500 | $11,500–$18,000 |
Your AC is over 15 years old
Repair costs exceed $3,000 or 50% of replacement cost
Your system uses R-22 refrigerant (phased out)
Frequent breakdowns or inconsistent cooling
Energy bills have increased significantly
Your AC runs constantly but doesn't cool properly
A good rule of thumb: if the repair cost multiplied by the system's age in years exceeds $5,000, replacement is usually the better investment. For example, a $1,500 repair on a 12-year-old system (1,500 × 12 = $18,000) strongly suggests replacement.