HVAC Replacement Cost in Knoxville, TN (2026)
Updated October 2026 · Knoxville, TN · index 0.91
How much does a new HVAC system cost in Knoxville? For a 3-ton system with central AC + gas furnace, homeowners in Knoxville, TN pay about $9,600 on average, and most quotes land between $6,550 and $12,600 — $2,178 to $4,208 per ton. The price covers removing the old system, the new outdoor and indoor equipment, a new line set, electrical and condensate connections, the thermostat, the permit, start-up and commissioning.
The HVAC replacement price in Knoxville runs 9% below the U.S. average: construction labor in the Knoxville area runs 15% below the national mean, materials 1% below. The same job averages $10,500 nationally and about $9,700 at the Tennessee statewide index.
HVAC Replacement cost calculator for Knoxville
1.5 to 5 ton
Are you a HVAC contractor? Price jobs like this in 60 seconds
HVAC replacement price in Knoxville by system type
What a 3-ton system costs in Knoxville with each system type, installed:
| Option | Average · range |
|---|---|
| Central AC + gas furnacesplit AC, matched coil and an 80,000 BTU furnace$3,193 per ton | $9,600$6,550 – $12,600 |
| Heat pump + air handlerall-electric split heat pump, no furnace$2,962 per ton | $8,900$5,950 – $11,800 |
| Cold-climate heat pump + air handlervariable-speed heat pump rated for deep winter$3,383 per ton | $10,100$6,850 – $13,500 |
The least expensive option in Knoxville is heat pump + air handler, at about $8,900; cold-climate heat pump + air handler averages $10,100, 1.1 times as much.
Cost to replace an HVAC system in Knoxville by size
With central AC + gas furnace, priced for Knoxville, TN:
| Size | Average · range |
|---|---|
| A 2-ton system$4,158 per ton | $8,300$5,700 – $11,000 |
| A 3-ton system$3,193 per ton | $9,600$6,550 – $12,600 |
| A 4-ton system$2,711 per ton | $10,800$7,400 – $14,300 |
Some costs stay the same whatever the size — load calculation and equipment sizing, mechanical permit and inspection, old system removed, refrigerant recovered — so a bigger job costs less per unit: $2,711 per ton for a 4-ton system against $4,158 for a 2-ton system.
What an HVAC replacement in Knoxville includes
Line by line, the $9,600 average for a 3-ton system breaks down like this: 32% labor, 65% materials and equipment, and $280 in permit fees passed through at cost.
| Line | Low – high |
|---|---|
| Load calculation and equipment sizing | $70 – $210 |
| Mechanical permit and inspection | $150 – $400 |
| Old system removed, refrigerant recovered | $310 – $550 |
| Gas furnace (about 80,000 BTU) | $1,400 – $2,500 |
| Outdoor unit, set on a new pad | $2,100 – $3,900 |
| Matched indoor coil | $900 – $1,950 |
| New refrigerant line set (25 ft) | $350 – $550 |
| Disconnect, whip and thermostat wire | $190 – $310 |
| Condensate drain and safety switch | $100 – $240 |
| Gas connection and furnace venting | $290 – $540 |
| Plenums and transitions to the ducts | $240 – $550 |
| Programmable or smart thermostat | $210 – $380 |
| Evacuation and refrigerant charge | $100 – $210 |
| Start-up and commissioning | $100 – $240 |
| Warranty registration and walk-through | $50 – $120 |
Each line is the price book's U.S. rate for that step, scaled by 0.76 to the installed price published sources give for the whole job (see how these prices are built), times Knoxville's index of 0.91; permit fees are not scaled.
Get free quotes from Knoxville contractors
Describe your project once and JobFlex sends it to a local HVAC contractor who prices it for your home — free, no account needed.
What affects HVAC replacement prices in Knoxville
Labor and materials in Knoxville
Construction wages in the Knoxville area run 15% below the U.S. mean (BLS, May 2025), and materials in its ZIP codes price 1% below the national average. Together they give Knoxville a construction cost index of 0.91.
Where Knoxville sits in Tennessee
Knoxville is the 6th most expensive of the 6 Tennessee cities in our index, against a statewide index of 0.92. Nashville is the dearest at 0.96; no Tennessee city in it costs less.
Against the rest of the country
Of the 306 U.S. cities in JobFlex's index, Knoxville ranks 256th from the most expensive. The job that averages $9,600 here averages $10,500 at the national rate.
Climate a system is sized for in Tennessee
Contractors size equipment for the local design temperatures. Across Tennessee's counties the median is about 93°F on a hot summer day and 15°F on a cold winter night (ENERGY STAR county table), and your county can differ. A standard heat pump handles most winters here; a furnace or a cold-climate model covers the coldest nights.
Sales tax in Tennessee
Tennessee's base state sales tax is 7%, and cities and counties can add their own. How it applies to a home-improvement contract varies, so ask whether a quote includes it. Prices on this page are before tax.
What a Knoxville contractor will ask before quoting
- Job type — new construction, replacement or upgrade — and the evidence for it
- Heating and cooling load for this house (not the old nameplate), tonnage, fuel and refrigerant
- Ducts, line set, circuit, gas line and flue: keep, fix or replace, each with its reason
- Water heater in scope, and whether it shared the old flue
- Panel main amps, free slots and the new equipment's MCA
- Permits, tests and incentives that apply in this state
HVAC replacement cost in other Tennessee cities
A 3-ton system with central AC + gas furnace averages $9,600 in Knoxville; $9,800 in Memphis, $9,800 in Chattanooga, $9,800 in Murfreesboro.
| City | Average · range |
|---|---|
| Memphis, TN2% more | $9,800$6,650 – $12,900 |
| Chattanooga, TN2% more | $9,800$6,650 – $12,900 |
| Murfreesboro, TN2% more | $9,800$6,650 – $12,900 |
| Franklin, TN5% more | $10,100$6,900 – $13,300 |
| Nashville, TN5% more | $10,100$6,900 – $13,300 |
HVAC replacement price in Knoxville: questions
How much does a new HVAC system cost in Knoxville, TN?
About $9,600 for a 3-ton system with central AC + gas furnace, and most Knoxville quotes fall between $6,550 and $12,600. That is 9% below the U.S. average, where the same job averages $10,500.
What is the HVAC price per ton in Knoxville?
$2,178 to $4,208 per ton, about $3,193 on average with central AC + gas furnace. Smaller jobs cost more per unit, because the fixed costs are spread over less.
How much is a 4-ton system in Knoxville?
$7,400 to $14,300, about $10,800 on average, with central AC + gas furnace — $2,711 per ton.
Do you need a permit for HVAC replacement in Knoxville?
Yes — installing HVAC or fuel-burning equipment needs a permit nearly everywhere, Knoxville included. The prices on this page carry $150–$400 for the permit and inspection.
Does the price include sales tax in Tennessee?
No. The prices here are before tax; Tennessee's base state rate is 7%, plus any local rate.
What size HVAC system does a house in Knoxville need?
It is worked out with a Manual J load calculation for the house — included in the prices above — not from square footage alone. Here it is run against design temperatures of about 93°F in summer and 15°F in winter (the Tennessee median).
Other home projects in Knoxville
HVAC replacement cost in Tennessee
How these prices are built
Every price on this page comes from JobFlex's contractor price book: what a homeowner pays a licensed contractor for each step of the job, as a U.S. national average per unit, with the contractor's overhead and profit included and sales tax left out. The HVAC replacement is priced step by step, then multiplied by Knoxville's construction cost index of 0.91.
Where the price book's steps for an option add up to more than 20% over the installed price a published source gives for the whole job, every step but a permit fee is scaled down to the middle of that range: central AC + gas furnace × 0.76 (HomeCostCalcs 2026: $7,000–$14,000); heat pump + air handler × 0.76, following central AC + gas furnace; cold-climate heat pump + air handler × 0.76, following central AC + gas furnace.
The index weighs local construction wages (BLS Occupational Employment and Wage Statistics, May 2025) at 60% and the area's material prices (Craftsman ZIP-area factors) at 40%. Published indices for Knoxville, each on its own base: HUD 0.89, Craftsman 1.03. Treat any city figure as about ±5%; a contractor's quote for your house is the number to plan with.
Contractors in Knoxville build quotes like these with JobFlex's HVAC estimator.
- HomeCostCalcs 2026: furnace + AC replacement $7,000-$14,000 standard, $10,000-$20,000 high efficiency
- Today's Homeowner 2025: complete HVAC system install $5,000-$12,500