Best HVACRepair Guide

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.

Short answer

A new furnace costs $3,000–$10,000 installed (gas). A central AC runs $4,500–$16,000 depending on home size (about $7,000–$11,500 for 2,000 sq ft), and a ducted heat pump $10,000–$25,000. Replacing furnace and AC together: $10,500–$18,500.

ESTIMATOR
What are you replacing?
ft²
Fuel
yrs
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  • 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

system age (years) × repair cost ($) > 5,000 → replace

A 6-year-old AC with a $500 repair scores 3,000: repair it. A 14-year-old AC with a $1,500 repair scores 21,000: put that money toward a new, more efficient unit. Scores close to 5,000 are a judgment call, so get a second quote.

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?

EquipmentTypical lifespan
Central AC15–20 years
Furnace15–30 years
Heat pump10–20 years
Source: HomeGuide 2026. Gas furnaces typically 15–25 years; electric 20–30.

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.

SizeBTUInstalled
1.5 tons18,000 BTU$4,700–$6,500
2 tons24,000 BTU$5,000–$6,800
2.5 tons30,000 BTU$5,400–$7,200
3 tons36,000 BTU$5,800–$7,800
3.5 tons42,000 BTU$6,200–$8,300
4 tons48,000 BTU$6,500–$8,800
5 tons60,000 BTU$7,000–$9,500
Entry-level efficiency, national average.
Home sizeAC tonsInstalled
1,000 ft²1.5 – 2$4,500–$7,000
1,200 ft²2 – 2.5$5,000–$7,500
1,500 ft²2.5 – 3$6,000–$8,500
1,600 ft²3 – 3.5$6,200–$9,000
1,800 ft²3 – 4$6,500–$10,000
2,000 ft²3.5 – 4.5$7,000–$11,500
2,200 ft²4 – 5$7,800–$12,500
2,500 ft²4.5 – 5$8,500–$13,500
3,000 ft²5+$10,000–$16,000+
Average total cost to replace a central AC by home size. Source: HomeGuide 2026.
Efficiency ratingTotal 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
SEER2 is the current DOE test standard (since 2023). Higher SEER2 costs more up front and less every month.

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 sizeInstalled
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
FuelInstalled
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 sizeInstalled
1,000 ft²$6,000–$8,500
1,500 ft²$8,000–$10,500
2,000 ft²$10,000–$20,000
2,500 ft²$12,000–$22,000
3,000 ft²$18,000–$25,000
3,500 ft²$20,000–$28,000
4,000+ 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). R-410A equipment manufactured or imported before 2025 can still be installed: a final EPA rule issued on May 21, 2026 removed the January 1, 2026 installation deadline for it. State rules can be stricter, so ask your installer. An existing R-410A system can still be 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.
Next toolRepair Cost

Frequently asked questions

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.

What is the average lifespan of an HVAC system?

With regular maintenance, a central AC lasts 15–20 years and a gas furnace 15–25 years. Heat pumps, which run year-round, last 10–20 years.

How much is a new HVAC system for a 2,000 sq ft house?

A new furnace and central AC installed together typically cost $10,500–$18,500. For a 2,000 sq ft home, the AC alone runs about $7,000–$11,500 and a gas furnace about $3,000–$6,500.

What time of year is it cheapest to replace an HVAC system?

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.

Best HVAC Repair GuideHVAC replacement cost & repair-or-replace calculator
Updated
ScaleNot to scale — national price ranges

Estimates for planning only. Prices vary by region, home, and contractor. Gas, refrigerant, and high-voltage work must be done by a licensed technician.