HVAC replacement cost & repair-or-replace calculator
Price a new furnace, central AC or heat pump for your home size, then put your current repair quote against it. The verdict uses the two rules contractors use themselves.
A new furnace costs $3,000–$10,000 installed (gas). A central AC runs $5,000–$9,500 by size, and a ducted heat pump $10,000–$25,000. Replacing furnace and AC together: $10,500–$18,500.
- Sourced range for your size
- Adjusted for your choice (derived)
Repair or replace? The two rules
Replace when age × repair cost is over $5,000, or when the repair is more than half the price of a new system. Otherwise, repairing is usually the better deal.
The $5,000 rule
A 6-year-old AC with an $800 compressor-capacitor repair scores 4,800: repair it. A 14-year-old AC with the same $800 repair scores 11,200: put that money toward a new, more efficient unit.
The 50% rule
If one repair costs more than half of what a replacement costs, replace, especially once the unit is past the middle of its expected life.
How long do AC units and furnaces last?
| Equipment | Typical lifespan |
|---|---|
| Central AC | 15–20 years |
| Furnace | 15–30 years |
| Heat pump | 10–20 years |
Central AC replacement and installation cost
A new AC for a 2,000 sq ft home is usually 3.5–4.5 tons and costs about $7,000–$11,500 installed.
Central air installation cost: replacing an existing central AC runs $5,300–$10,500. Adding central air to a home without ducts costs $9,000–$16,000, because the ductwork is part of the job. Cost of a new HVAC system (AC and furnace together): $10,500–$18,500.
| Size | BTU | Installed |
|---|---|---|
| 1.5 tons | 18,000 BTU | $4,700–$6,500 |
| 2 tons | 24,000 BTU | $5,000–$6,800 |
| 2.5 tons | 30,000 BTU | $5,400–$7,200 |
| 3 tons | 36,000 BTU | $5,800–$7,800 |
| 3.5 tons | 42,000 BTU | $6,200–$8,300 |
| 4 tons | 48,000 BTU | $6,500–$8,800 |
| 5 tons | 60,000 BTU | $7,000–$9,500 |
| Home size | AC tons |
|---|---|
| 1,000 ft² | 1.5 – 2 |
| 1,200 ft² | 2 – 2.5 |
| 1,500 ft² | 2.5 – 3 |
| 1,600 ft² | 3 – 3.5 |
| 1,800 ft² | 3 – 4 |
| 2,000 ft² | 3.5 – 4.5 |
| 2,200 ft² | 4 – 5 |
| 2,500 ft² | 4.5 – 5 |
| 3,000 ft² | 5+ |
| Efficiency rating | Total installed |
|---|---|
| 13–14 SEER (≤13.4 SEER2) | $5,300–$7,900 |
| 15–16 SEER (14–14.7 SEER2) | $6,700–$9,300 |
| 17–18 SEER (15–17.2 SEER2) | $7,500–$10,600 |
| 19–21 SEER (16.5–18.5 SEER2) | $9,100–$12,200 |
| 22–26 SEER (up to 25.8 SEER2) | $11,400–$17,300 |
New furnace cost by home size and fuel
A new furnace for a 1,500–2,500 sq ft home costs $3,000–$6,500 installed. Gas furnaces run $3,000–$10,000 depending on efficiency and venting.
| Home size | Installed |
|---|---|
| 1,000–1,500 ft² | $2,000–$4,500 |
| 1,500–2,500 ft² | $3,000–$6,500 |
| 2,500–3,500 ft² | $4,000–$9,500 |
| 3,500+ ft² | $5,500–$10,000 |
| Fuel | Installed |
|---|---|
| Natural gas | $3,000–$10,000 |
| Electric | $2,500–$7,000 |
| Oil | $4,000–$10,000 |
| Propane | $3,000–$12,000 |
Heat pump installation cost by home size
An air-source heat pump costs $10,000–$25,000 installed for most homes. It replaces both the AC and the furnace in mild and moderate climates.
| Home size | Installed |
|---|---|
| ≤ 1,000 ft² | $6,000–$8,500 |
| 1,000–1,500 ft² | $8,000–$10,500 |
| 1,500–2,000 ft² | $10,000–$20,000 |
| 2,000–2,500 ft² | $12,000–$22,000 |
| 2,500–3,000 ft² | $18,000–$25,000 |
| 3,000–3,500 ft² | $20,000–$28,000 |
| 3,500+ ft² | $22,000–$32,000 |
What changed for 2026 buyers
Three rule changes affect a 2026 replacement: new refrigerants, higher minimum efficiency, and the end of the federal 25C tax credit.
New refrigerants: R-454B and R-32
Since January 1, 2025, new central AC and heat pump systems must be built with lower-GWP refrigerants, mainly R-454B (ducted systems) and R-32 (ductless). Equipment built with R-410A before 2025 can still be installed: in December 2025 the EPA said enforcing the 2026 installation cutoff is a low priority while it reconsiders the rule. An existing R-410A system can keep being repaired and recharged.
Minimum efficiency (SEER2)
Since 2023, a new split central AC must be at least 13.4 SEER2 in the North and 14.3 SEER2 in the Southeast and Southwest. When the outdoor unit is replaced, the indoor coil usually has to be replaced too so the pair is rated together.
The federal 25C tax credit has ended
The Energy Efficient Home Improvement Credit (up to $2,000 for heat pumps) does not apply to equipment installed after December 31, 2025. If you installed in 2025, you can still claim it on your 2025 return with IRS Form 5695. For 2026 installs, look at utility and state rebates instead.
How to pay less for a new system
- Replace in spring or fall. Contractors are less busy between cooling and heating seasons, and an unhurried install beats an emergency one in July.
- Get three written quotes with model numbers, so you compare the same equipment.
- Ask for a load calculation (Manual J) instead of a same-size swap. Oversized units cost more and short-cycle.
- Check utility and state rebates for high-efficiency equipment before you sign. The federal 25C credit no longer applies to 2026 installs.
Questions homeowners ask
How much is a new AC unit for a 2,000 sq ft house?
About $7,000–$11,500 installed for a 3.5–4.5 ton central AC at standard efficiency. High-efficiency (SEER2 16+) units add a few thousand dollars.
How much does a new furnace cost for a 2,000 square foot house?
Typically $3,000–$6,500 installed. Electric furnaces are cheaper to install; high-efficiency (95%+ AFUE) gas furnaces cost more because they need PVC venting and a condensate drain.
Is it worth replacing a 30-year-old furnace?
Usually yes. Thirty years is past the 15–25 year life of most gas furnaces, older units often run at 60–80% efficiency versus 95%+ today, and an aging heat exchanger is a carbon-monoxide risk. Replace it on your schedule rather than after a mid-winter failure.
How many years should an AC last?
A central AC lasts 15–20 years with regular maintenance. Heat pumps, which run year-round, last 10–20 years.
What time of year is cheapest to replace HVAC?
Spring and fall. Demand drops between seasons, so you have room to compare quotes and schedule the install instead of paying emergency rates.
Should I replace my AC and furnace at the same time?
If both are within a few years of the end of their life, yes: one install visit, matched equipment, and a single warranty. Replacing both costs about $10,500–$18,500.
Estimates for planning only. Prices vary by region, home, and contractor. Gas, refrigerant, and high-voltage work must be done by a licensed technician.