Cost to Replace a 5-Ton AC Unit and Furnace

The cost to replace a 5-ton AC unit and furnace depends on equipment quality, installation complexity, efficiency ratings, ductwork condition, local labor rates, and permit requirements. This guide breaks down typical price ranges, decision factors, financing options, and ways to get accurate estimates for homeowners in the United States.

Item	Typical Cost Range (Materials & Labor)	Notes
5-Ton Air Conditioner (Condensing Unit)	$3,000 – $6,500	Depends on SEER rating and brand
Indoor Coil / Air Handler	$800 – $2,500	Matches outdoor unit; variable-speed adds cost
Gas Furnace (Replacement)	$2,500 – $7,500	AFUE rating and modulating/blower type affect price
Full System (AC + Furnace)	$8,000 – $16,000+	Includes basic installation; higher for premium equipment or ductwork
Ductwork Repair/Replacement	$1,000 – $10,000+	Major variable—adds significantly if needed
Permits & Miscellaneous	$200 – $1,000+	Local codes and inspections vary

How Replacement Costs Are Calculated

Replacing a 5-ton AC unit and furnace combines equipment, labor, materials, and indirect costs. Equipment includes the condenser, indoor coil or air handler, and furnace. Labor varies by region and installer expertise. Materials include refrigerant lines, electrical, thermostats, vents, and mounting hardware.

Additional charges may appear for permits, electrical upgrades, gas line adjustments, and hauling old equipment. Installers typically provide itemized quotes to explain the cost breakdown.

Average Price Ranges For Major Components

5-Ton Outdoor Condenser

A 5-ton outdoor unit typically costs between $3,000 and $6,500 installed. Lower-cost models have standard efficiency (13–15 SEER), while higher-end units (16–22+ SEER) and inverter-driven compressors increase the price.

Indoor Coil Or Air Handler

Indoor components range from $800 to $2,500. Matched systems (same brand/series) ensure warranty coverage and optimal performance. Variable-speed air handlers add comfort but increase cost.

Gas Furnace

Furnace replacement usually falls between $2,500 and $7,500. Basic single-stage furnaces are cheaper; mid-efficiency (80–95% AFUE) and high-efficiency condensing furnaces with two-stage/modulating burners cost more.

Ductwork

Duct repair can be modest ($200–$1,000) or extensive ($2,000–$10,000+). Undersized, leaky, or poorly insulated ducts reduce system efficiency and should be evaluated before installation.

Key Factors That Increase Or Decrease Cost

• Equipment Efficiency: Higher SEER and AFUE ratings cost more but lower utility bills.
• System Type: Matched systems and heat pumps differ in cost compared to split AC + furnace combinations.
• Installation Complexity: Attic, crawlspace, or multi-story installations take longer and may require lifts or special access.
• Duct Condition: Repairing or replacing ducts raises the total significantly.
• Local Labor Rates: Urban and high-cost-of-living areas charge more for labor.
• Permit And Code Requirements: Some jurisdictions require inspections and specialized materials.
• Electrical Or Gas Upgrades: Subpanels, 240V circuits, or gas line modifications add cost.

Energy Efficiency, Rebates, And Long-Term Savings

Choosing higher-efficiency equipment increases upfront cost but reduces operating expenses. A 16–22 SEER AC can use 20–40% less electricity than a 13 SEER unit. High-efficiency furnaces with AFUE ratings of 95%+ substantially reduce fuel use.

Many utility companies, state programs, and federal incentives offer rebates or tax credits for high-efficiency systems or heat pumps. Always check current incentives to lower net cost.

Installation Best Practices And What To Expect

An accurate installation involves load calculation (Manual J), duct design (Manual D), and airflow testing (Manual S recommendations). Proper sizing of a 5-ton unit is crucial—oversizing shortens equipment life and reduces comfort.

Reliable contractors will inspect existing ductwork, electrical, and gas systems and provide a written estimate, timeline, warranty details, and a performance checklist after installation.

Common Add-Ons And Their Costs

• Thermostat Upgrade (Smart, Zoning): $200 – $900
• Line Set Replacement: $200 – $800
• Electrical Circuit/Panel Upgrade: $500 – $3,000
• Additional Registers/Grilles: $50 – $200 each
• Condensate Pump (if needed): $100 – $500
• Zone Dampers And Controls: $800 – $3,500

Financing Options And Return On Investment

Many HVAC companies offer financing plans, often with promotional 0% APR periods. Home equity lines, personal loans, and energy-efficient financing programs are alternatives. Financing spreads cost but increases total paid if interest applies.

Estimate payback by comparing the premium paid for high-efficiency equipment against annual savings in energy bills. Typical payback periods range from 3 to 10 years depending on usage, fuel cost, and equipment efficiency improvement.

How To Get Accurate Quotes

1. Request at least three itemized quotes from licensed HVAC contractors.
2. Ask for Manual J load calculations and documentation of duct testing.
3. Verify contractor licensing, insurance, and customer reviews.
4. Compare warranties: parts, labor, and compressor coverage.
5. Confirm whether the quote includes permits, disposal, and startup testing.

Questions To Ask A Contractor

• Is the 5-ton recommendation based on a Manual J calculation?
• Will the replacement be a matched system from the same manufacturer?
• What efficiency ratings (SEER, AFUE) are included?
• What warranties come with equipment and labor?
• Are permits and inspections included in the price?

Sample Cost Scenarios

Budget Replacement

Lower-end equipment with basic installation for a 5-ton AC and standard furnace: approximately $8,000–$10,000. This scenario usually uses standard-efficiency units and minimal ductwork work.

Mid-Range Replacement

Mid-efficiency matched system with some duct sealing and a programmable thermostat: approximately $10,000–$13,500.

High-End Replacement

High-efficiency inverter AC, modulating furnace, major duct replacement, and zoning: approximately $14,000–$22,000+.

Maintenance Tips To Protect A New System

• Change filters every 1–3 months depending on type and home conditions.
• Schedule annual professional tune-ups for both AC and furnace.
• Keep outdoor condensers clear of debris and maintain 2–3 feet of clearance.
• Monitor airflow and unusual noises; address quickly to avoid major repairs.

When To Replace Versus Repair

If the existing system is over 10–15 years old, requires frequent repairs, uses obsolete refrigerants (R-22), or shows rising energy bills, replacement often yields better value than repeated repairs.

Consider replacement if repair costs exceed 50% of the value of a new system or if efficiency improvements will pay back the investment in a reasonable time.

How Regional Factors Affect Cost

Labor rates and permit fees differ by state and city. Climate influences system selection—colder regions may prioritize high-AFUE furnaces; hotter climates may invest more in high-SEER AC units. Local code requirements can mandate specific efficiency levels or insulation standards.

Frequently Asked Questions

Will Replacing Both At The Same Time Save Money?

Replacing the AC and furnace simultaneously can reduce labor costs, ensure matched components, and improve overall efficiency. Combined replacement often offers better warranty terms and a streamlined installation.

Is A 5-Ton Unit Always The Right Size?

Not always. The correct size should result from a Manual J calculation that considers house insulation, window area, orientation, occupancy, and duct losses rather than relying on square footage alone.

Can A 5-Ton Unit Be Installed On Existing Ductwork?

Possibly, but ductwork should be inspected and tested. Undersized or leaky ducts may prevent the new 5-ton system from delivering proper airflow and efficiency.

Finding A Qualified Installer

Choose contractors with state licensing, good reviews, clear warranties, and strong local references. Verify that installers perform load calculations and offer written, itemized bids. A trustworthy contractor will explain trade-offs between short-term cost and long-term energy savings.

Resources And Incentives

Homeowners can check federal energy incentives, state energy office programs, and local utility rebates. ENERGY STAR and the Database of State Incentives for Renewables & Efficiency (DSIRE) are useful starting points for current incentives.

For precise budgeting, request onsite quotes and include contingencies of 10–20% for unexpected issues discovered during installation.