Lennox furnace and air conditioner prices typically range from $8,000 to $18,000 for a combined replacement, with many standard, professionally installed systems near $12,000. The final quote depends on equipment size and efficiency, local labor, ductwork condition, electrical or venting changes, and whether the furnace and AC are replaced together.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Gas furnace installed | $4,500 | $7,000 | $11,000 | Typical home, standard installation |
| Central AC installed | $5,000 | $8,000 | $12,000 | Includes indoor coil and outdoor unit |
| Furnace and AC together | $8,000 | $12,000 | $18,000 | Bundled replacement, standard ductwork |
| Equipment only | $2,500 | $5,500 | $9,000 | Furnace and AC equipment; excludes installation |
Assumptions: U.S. dollars, residential split systems, existing usable ductwork, typical access, and licensed contractor installation. Premium equipment, high-cost metro areas, and major system modifications can exceed the ranges.
What Lennox furnace and AC systems typically cost
A Lennox gas furnace alone commonly costs $4,500-$11,000 installed. A central air conditioner replacement commonly costs $5,000-$12,000 installed, including an outdoor condenser and compatible indoor evaporator coil. Costs vary with capacity, efficiency, controls, and the amount of labor needed to adapt existing connections.
Replacing both appliances at the same time generally runs $8,000-$18,000. A straightforward job using entry-level or midrange equipment may fall around $9,000-$13,000; a high-efficiency furnace paired with a premium variable-capacity AC can reach $15,000-$22,000 or more. A combined quote is not necessarily the sum of two separate installs because shared labor and setup may reduce duplication.
Lennox equipment is sold in multiple product tiers, and model names and current lineups can change. Ask the contractor to identify the exact model numbers, furnace input capacity, AC tonnage, efficiency ratings, and included controls rather than comparing estimates by brand name alone. For a typical home with sound ducts, budget about $8,000-$18,000 for a professionally installed Lennox furnace-and-AC replacement.
How furnace, coil, condenser and labor shape the quote
The equipment is only one part of the installed price. The estimate may include a furnace, outdoor AC condenser, indoor coil, thermostat or communicating control, refrigerant line work, venting, electrical connections, startup testing, and disposal of the old appliances. A contractor should list these items separately so a lower bid does not simply omit necessary work.
| Quote component | Typical range | What changes the price | Common unit |
|---|---|---|---|
| Gas furnace equipment | $1,500-$4,500 | Efficiency, capacity, and stages | Per furnace |
| AC condenser and indoor coil | $2,000-$6,000 | Tonnage, efficiency, and compatibility | Per system |
| Installation labor | $1,500-$4,000 | Access, crew time, and system changes | Per project |
| Controls and electrical work | $150-$1,200 | Thermostat type and circuit changes | Per project |
| Removal and disposal | $150-$600 | Number of units and local disposal fees | Per project |
| Permit and inspection | $75-$500 | City or county requirements | Per project |
Labor commonly represents a substantial share of the quote because technicians must remove equipment, connect gas and electrical service, fit the coil and refrigerant lines, and verify safe operation. Rates vary widely; a planning allowance of $75-$150 per technician-hour is useful, but contractors typically quote installation as a project rather than billing every hour separately.
Compare the complete scope, not just the furnace or condenser line item. A quote should explain whether it includes a new indoor coil, refrigerant recovery, startup, permits, disposal, and correction of code-related issues found during installation.
Which tonnage, efficiency and ductwork raise estimates
AC capacity is a major price driver. A smaller home may use a 2-ton system, while larger or hotter homes may need 3-5 tons. As a broad installed planning range, each additional ton can add roughly $500-$1,500, depending on the equipment tier and any changes needed to the coil, refrigerant piping, electrical circuit, or ductwork. Correct sizing requires a load calculation; square footage alone is not enough.
Furnaces are commonly sized around 40,000-100,000 BTU per hour for residential homes. Higher capacity can raise equipment and venting costs, but an oversized unit may cycle inefficiently and provide uneven comfort. A variable-speed blower or two-stage burner often costs more than a basic single-stage design; ask for the model-specific price difference instead of assuming all furnaces in one size cost alike.
Efficiency also affects the budget. Entry-level gas furnaces often have AFUE ratings around 80%-96%, while premium models may provide more precise staging and quieter operation. Central AC equipment commonly spans about 14-20 SEER2, depending on product tier and configuration. Higher-efficiency choices can add $1,000-$4,000 or more to a combined quote, especially when they require communicating controls or installation changes.
Duct leakage, undersized returns, damaged insulation, or a tight attic or crawlspace can add $500-$3,000 or more. Replacing a section of duct may cost about $25-$60 per linear foot, while extensive duct redesign can exceed $5,000. The biggest quote jumps often come from changing capacity, selecting premium efficiency, or correcting ductwork—not from the brand label alone.
How to lower the Lennox replacement price without cutting essentials
Replacing both systems together can avoid separate removal visits and repeated setup, but only when both appliances are near the end of their useful service life or have a clear performance problem. If one unit is relatively new and repairable, get a separate repair estimate before accepting a full-system replacement. A failed part does not automatically mean the entire system needs replacement.
Compare at least three written bids based on the same design conditions: model numbers, capacity, efficiency, thermostat, coil, labor scope, warranty, permits, and disposal. Request a load calculation and ask contractors to explain any difference in tonnage. A quote with a cheaper unit but no coil replacement or permit allowance may not be a true lower-cost alternative.
Standard single-stage equipment may be sufficient for a home with modest comfort needs and well-designed ducts. Compare the installed premium for two-stage or variable-capacity equipment with the expected comfort and operating benefits; do not pay for a feature without a specific reason. Keep existing thermostats or line sets only if the installer confirms compatibility and safe condition.
Scheduling before extreme summer or winter demand may provide more appointment flexibility, although savings are not guaranteed. Clear the work area, arrange access to the furnace and outdoor unit, and confirm whether the contractor charges extra for difficult access. Control scope and compare equivalent bids before choosing a lower-priced model or skipping recommended safety work.
How many hours a Lennox installation takes
A straightforward furnace-only replacement commonly takes 6-10 hours, and an AC-only replacement often takes 6-10 hours. A combined furnace and AC job generally takes one full day, or about 8-14 crew-hours of on-site work, assuming existing equipment locations, usable ductwork, and no major code corrections. A two-person crew may finish within a day even though total labor hours add up across both workers.
Jobs involving new refrigerant lines, a difficult attic location, venting changes, electrical upgrades, or duct repairs can take 1-3 days. The crew may also need a return visit if permits require an inspection before final closeout. Ask whether the estimate includes commissioning tests, such as airflow checks, refrigerant charge verification, combustion testing, and thermostat setup.
Labor pricing can be difficult to compare when bids use fixed project rates. A contractor quoting $2,000 for installation might include a larger crew and startup work, while a lower labor allowance could exclude electrical changes or additional duct fittings. Confirm the expected crew size, job duration, and included startup tasks in writing.
Lennox pricing compared with Goodman and Carrier
For a broadly comparable installed furnace-and-AC setup, Lennox often falls in the midrange to premium portion of the market. As a planning comparison, Goodman systems may be about 5%-20% less, while Carrier systems may be roughly 0%-15% more or comparable, depending on equipment tier, contractor pricing, and local availability. These are not fixed brand-wide price rules.
Compare matched specifications rather than comparing a basic Lennox system with a premium competing model. Useful details include furnace stages and AFUE, AC SEER2 and capacity, blower type, sound ratings, controls, labor warranty, and parts warranty. The quality of sizing, installation, and follow-up service can influence performance and repair costs as much as the equipment brand.
Warranty coverage can differ by model and registration terms. Ask what the parts warranty covers, whether registration is required by a deadline, how long labor coverage lasts, and whether a contractor service plan is optional. A longer parts warranty does not necessarily include labor or refrigerant-related service charges. Use the same capacity and feature level when comparing Lennox with Goodman or Carrier quotes.
What removal, permits and duct repairs add to Lennox quotes
Old-equipment removal and disposal typically add $150-$600 when they are not included in the base installation price. A local permit and inspection may cost $75-$500, with larger charges possible in jurisdictions requiring multiple permits or additional reviews. These costs vary by city and county, so the estimate should state whether permit fees are included or billed separately.
Common extra work includes a new thermostat at $150-$700, a condensate pump at $100-$300, and electrical or disconnect changes at roughly $200-$1,000. Refrigerant line replacement can add about $500-$2,000, depending on length and accessibility. Duct repairs may be priced by the section, by the foot, or as a project; ask for a written description of the affected runs and sealing or insulation work.
Some homes need gas piping, venting, condensate drainage, or combustion-air corrections to meet current code. Minor adjustments may add a few hundred dollars, while extensive upgrades can add $1,000-$3,000 or more. These should be documented as separate line items, with the reason and applicable scope stated. Request an itemized allowance for disposal, permits, electrical work, refrigerant piping, and duct repairs.
How Midwest and coastal labor markets shift installed prices
Regional labor, permit fees, housing access, and contractor demand can shift a Lennox quote substantially. A straightforward replacement in a lower-cost Midwest or rural market may come in 5%-15% below a national planning estimate. Major coastal metros and high-cost Western cities can run 10%-25% above it, particularly where labor rates, parking, permitting, or installation logistics are expensive.
Climate affects equipment selection as well as installation. Homes in long, cold winters may need a furnace with capacity and venting suited to local design temperatures, while hot, humid markets may prioritize AC performance, moisture removal, and duct sealing. A higher-tonnage system is not automatically appropriate in a hot climate; sizing should account for insulation, windows, air leakage, and cooling load.
For a combined system quoted at a $12,000 national planning average, a 10%-15% regional adjustment represents approximately $1,200-$1,800. The actual difference may be smaller or larger based on the contractor and job scope. Compare local quotes using the same model numbers and included work rather than treating a regional percentage as a guaranteed discount or surcharge. Local bids are the best measure of regional pricing because labor and code requirements vary by jurisdiction.
Three Lennox furnace and AC quote examples
Basic replacement: A 1,500-square-foot home with existing ducts, a 60,000-BTU furnace, and a 2.5-ton standard-efficiency AC might receive a $9,000-$11,500 quote. This assumes a direct equipment swap, a basic thermostat, routine disposal, and no electrical or duct modifications.
Midrange replacement: A 2,000-square-foot home with a 70,000-BTU two-stage furnace and a 3-ton mid-efficiency AC might cost $11,500-$15,500 installed. The estimate may include a compatible coil, upgraded controls, permit fees, and about 10-14 crew-hours, with only minor duct sealing.
Premium replacement: A 2,800-square-foot home with a 90,000-BTU high-efficiency furnace, variable-speed blower, and 4-ton variable-capacity AC might cost $16,000-$23,000 or more. The upper end can include communicating controls, new refrigerant lines, difficult access, and duct corrections. A load calculation and equipment compatibility review are especially important at this scale.
These examples illustrate how scope changes the total; they are not model-specific offers. When a contractor proposes a price far outside the ranges, ask which equipment features, site work, warranty coverage, or local requirements explain the difference. A useful quote states the equipment model numbers, capacity, labor scope, and all allowances in one document.