HVAC Replacement Cost Calculator: AC, Heat Pump & Furnace

Conditioned floor area

sq ft

Heated and cooled living space only — skip garages and unfinished basements.

Climate

Hot (about 400 sq ft per ton)Gulf Coast, desert SouthwestMixed (about 500 sq ft per ton)Mid-Atlantic, central statesCold / mild summers (about 600 sq ft per ton)Northern states, mild summers

Sets the rule-of-thumb floor area per ton of cooling.

System to install

Central air conditioner$5,000–$9,500 installed (2–5 ton)Heat pump (heating + cooling)$10,000–$25,000 whole-homeGas furnace only$2,823–$6,897 installedCentral AC + gas furnaceBoth ranges added together

Current system SEER2

Check the yellow EnergyGuide label or the model number. Systems from before 2006 are often SEER 10 or lower.

New system SEER2

Central air conditioner installed

4-ton size for 2,000 sq ft · mixed climate · national average prices

Estimated sizeAbout 48,000 BTU/h

Floor area per tonRule of thumb, mixed climate

Annual cooling savings$1,048 → $699 a year

Simple paybackMidpoint cost ÷ annual cooling savings

Square-feet-per-ton is only a rule of thumb. Ask the contractor for a Manual J load calculation before choosing a size — an oversized system short-cycles, dehumidifies poorly and costs more up front.

Key takeaways

The rule of thumb sizes this home at 4 tons (2,000 sq ft ÷ 500 sq ft per ton).
Going from SEER2 10 to 15 cuts cooling electricity by 33% (1,920 kWh a year).
At $349 a year in savings, the midpoint price takes about 22 years to pay back on cooling alone.

Installed cost estimate

Central AC, 4 ton, installedEquipment, labor and standard materials for a like-for-like replacement.$6,500 – $8,800

Installed cost by system type (4 tons)

Annual cooling cost by SEER2

Detailed numbers

Central AC installed cost by size
Size	Covers about	Installed cost
2 ton	1,000 sq ft	$5,000 – $6,800
3 ton	1,500 sq ft	$5,800 – $7,800
4 ton	2,000 sq ft	$6,500 – $8,800
5 ton	2,500 sq ft	$7,000 – $9,500

Floor area at 500 sq ft per ton for the selected climate. Prices adjusted for your local cost level.

Annual cooling cost for a 4 ton system
SEER2	Electricity	Cooling cost	Saves vs current
13	4,431 kWh	$806	$242
15	3,840 kWh	$699	$349
17	3,388 kWh	$617	$432
20	2,880 kWh	$524	$524

1,200 cooling hours per year at $0.182 per kWh. Current system: SEER2 10 = 5,760 kWh/yr.

Show the math

2,000 sq ft ÷ 500 sq ft per ton = 4 tons → 4 tons (nearest ½ ton, 1.5–5 ton limits)
Central AC, 4 ton, installed: $6,500 – $8,800
Midpoint installed cost = $7,650
Current: 4 tons × 12,000 BTU/h × 1,200 h ÷ (SEER2 10 × 1000) = 5,760 kWh/yr
New: 4 tons × 12,000 BTU/h × 1,200 h ÷ (SEER2 15 × 1000) = 3,840 kWh/yr
Savings = 1,920 kWh × $0.182 = $349.44 per year
Simple payback = $7,650 ÷ $349.44 = 21.9 years

HVAC Replacement Cost Calculator · BuildCalc

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Prices & assumptionsNational typical prices