Lennox Furnace Prices & Installation Cost in Woodstock, IL and Chicagoland (2026)

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Illustrative Lennox installed-price examples are $4,785 for ML180UH045E36AK and $7,137.50 for SLP99UH070XV36BK; estimates depend on size, efficiency and what your ductwork and venting need. Lennox identifies the furnace model suffix K as refrigerant detection-ready. The exact furnace, indoor coil, controls and detection components must be checked for the proposed system. Website prices are budget guides before available rebates, not binding quotes. Every installation is custom; an in-home consultation is required for your final written estimate. Final cost may be lower or higher; eligible rebates may reduce it.

At a glance
Installed price examples$4,785 (ML180UH045E36AK); $7,137.50 (SLP99UH070XV36BK). Final pricing depends on equipment sizing and installation requirements
SeriesMerit® (value) · Elite® (better) · Dave Lennox Signature® Collection (best)
Efficiency80% AFUE to up to 99% AFUE, depending on the exact model
R-454B readyK denotes refrigerant detection-ready; exact equipment and detection-component compatibility must be verified
WarrantyCoverage varies by exact model, application, registration and selected warranty option; review the applicable Lennox warranty certificate
RebatesNicor Gas: $225 (97%+ AFUE) / $150 (95%+ AFUE) in 2026 · Lennox seasonal promotions
TimelineIn-home estimate → confirm equipment availability, installation scope and scheduling
FinancingSynchrony, Service Finance Company, rent-to-own (Microf)
Want a Lennox furnace price for your home?
Free in-home estimate with a heating load calculation. Same-week installation in most of McHenry, Lake, Kane, Cook and DuPage counties.

Lennox furnace installation by county. GSHA Services is a Lennox Premier Dealer. See the Lennox pages for McHenry County, Lake County, Kane County, DuPage County, Cook County and Will County for local permit rules, gas-utility rebate programs and the communities we serve in each county.

Find your county: GSHA, an authorized Lennox dealer, serves

McHenry · Lake · Cook · Kane · DuPage · Will · Boone County, IL

What does the “K” at the end of a Lennox furnace model mean?

Lennox uses the furnace model suffix K for refrigerant detection-ready equipment. Compatibility with an R-454B cooling system depends on the exact furnace, indoor coil, controls and required detection components. The coil and furnace installation instructions determine the required configuration.

  • Compare exact models. Heating ratings, controls, dimensions and warranty terms should be checked for the specific equipment selected.
  • Planning a cooling upgrade: confirm the matched equipment and required refrigerant detection components before selecting a replacement furnace.
  • Furnace-only replacements: compatibility with the existing coil and controls must be confirmed for your installation.

Which Lennox furnace should you buy? Merit vs. Elite vs. Signature

Lennox sells three tiers. The right one depends on how long you plan to stay in the house, how uneven your rooms feel today, and whether you want a communicating smart thermostat. Here is how we explain them at the kitchen table:

Series2026 models (K)AFUEHeatingBest forEstimated installed price
Merit®ML180EK, ML180VK, ML196EK, ML296VK, ML297VK80–97%Single-stage (ML1xx) or two-stage (ML29x)Budget replacement, rentals, homes you may sell within 5–7 years$4,785 (ML180EK)
Elite®EL280EK, EL296EK, EL296VK, EL297EK, EL297VK80–97%Two-stage (constant-torque or variable-speed blower)Most families: quieter, even heat, better humidity control, lifetime heat exchanger on 96–97% models$5,213.75 (EL280EK); $6,511.25 (EL297VK)
Dave Lennox Signature®SL280VK, SLP99VK80% / 99%Two-stage variable-speed or fully modulatingForever homes, allergy or noise-sensitive households, whole-home iComfort S40 systems$5,450 (SL280VK); $7,137.50 (SLP99VK)

Ultra-low-NOx versions (SL297NVK, SL280NVK, EL195NEK, EL180NEK) are regional products built for California air-quality rules; ask us to confirm suitability and current availability for your installation.

Merit® Series Lennox furnace prices

Merit® Series furnaces are Lennox’s value line and the most popular choice when a furnace fails mid-winter and you need reliable heat at the lowest price from a top-tier brand. All Merit models use efficient ECM blower motors (Power Saver™ constant-torque on the “E” models, full variable-speed on the “V” models) with heat-exchanger coverage determined by the exact model and applicable warranty certificate. The two-stage ML296VK and the new 97% ML297VK bring Elite-style comfort into the Merit price band.

Elite® Series Lennox furnace prices

Elite® Series furnaces are the sweet spot for most Chicagoland homes. Selected Elite models offer two-stage heating. Warranty coverage is model-specific. Qualifying models rated at least 97% AFUE may be eligible for the $225 Nicor Gas rebate when all program requirements are met. Choose a “V” (variable-speed) model if you have an air conditioner or heat pump, humidity problems or want the quietest operation; the “E” (constant-torque) models save a few hundred dollars.

Dave Lennox Signature® Collection furnace prices

The Signature® Collection is the best furnace Lennox makes. The SLP99VK is a fully modulating, variable-speed furnace rated up to 99% AFUE — with the exact efficiency rating depending on the selected configuration — and with an iComfort® S40 thermostat it adjusts its output in tiny increments to hold your setpoint within half a degree. The SL280VK is the top 80% AFUE furnace for homes where high-efficiency venting is impractical. Both feature SilentComfort™ sound-dampening design. Warranty coverage depends on the exact model, application, registration and selected coverage option.

* Website prices are budget guides before available rebates, not binding quotes. Every installation is custom; an in-home consultation is required for your final written estimate. Final cost may be lower or higher; eligible rebates may reduce it. A heating load calculation is required to size your furnace correctly.

What affects the price of a Lennox furnace installation?

  • Furnace size (BTU/h). Chicagoland homes usually need 60,000–110,000 BTU/h. We size to a heating load calculation for a -20°F design day, not a guess, and we select toward the upper end of the allowed range so the house holds temperature on the coldest nights.
  • Efficiency and venting. 80% furnaces vent through the existing chimney or metal flue. 93–99% condensing furnaces need PVC intake/exhaust and a condensate drain (sometimes a condensate pump), which adds material and labor but saves 15–20% on gas every winter.
  • Stages and blower. Two-stage and modulating furnaces with variable-speed blowers cost more up front and pay it back in comfort, quieter operation and lower electric use.
  • Thermostat. A Lennox iComfort® S40 unlocks communicating features on Elite “V” and Signature models; we also install ecobee and Nest.
  • Your ductwork. Plenums, transitions, a new filter cabinet (we recommend a 4-inch media filter), return-air upgrades and sealing.
  • Permits and inspection. Included in every quote — we pull the mechanical permit in your village and meet the inspector.

Rebates & incentives for 2026

  • Nicor Gas 2026 rebates: $225 for a 97%+ AFUE furnace, $150 for 95%+ AFUE, $25 for a qualifying smart thermostat, plus a $25 bonus when the furnace and thermostat are on the same application. Equipment must be installed Jan 1–Dec 31, 2026 and applied for within 90 days (or by Jan 31, 2027). GSHA prepares the paperwork for you.
  • Manufacturer offers: see the current Lennox promotion and Carrier Cool Cash (through November 20, 2026) pages for dates and qualifying systems.
  • Federal 25C tax credit: the 30% Energy Efficient Home Improvement credit ended for equipment placed in service after December 31, 2025, so it does not apply to 2026 installations. Utility rebates and manufacturer promotions still do.

All current promotions · Financing · Tax credit history

Financing — apply online in minutes

Flexible monthly payments for qualified customers. Pick the lender that fits your budget; approval usually takes minutes.

Synchrony Financial

  • No-interest-if-paid-in-full promotional plans
  • Fixed monthly payment options
  • Fast credit decision
Apply with Synchrony
Subject to credit approval.

Service Finance Company

  • Short- and long-term plans
  • Low fixed APR options
  • Home-improvement lender
Apply with Service Finance
Subject to credit approval.

Rent-to-Own (Microf)

  • Options for challenged credit
  • No credit-score minimum on most plans
  • Own the system at the end of the term
Rent-to-own details
See program terms.

Why buy your Lennox furnace from GSHA Services?

  • Lennox Premier Dealer with two local offices — Woodstock (McHenry County) and Lake Bluff (Lake County) — serving homes within about 50 miles, including southern Wisconsin.
  • Every install gets a load calculation, combustion analysis and a permit. We set gas pressure and temperature rise to Lennox specs, test for CO and leave you the combustion printout.
  • Upfront, written price before we start — no surprise charges. Free in-home estimates and free second opinions on cracked heat exchangers.
  • We service what we sell, 24/7. Emergency repair, annual tune-ups and our GSHA PROTECT maintenance plan.
  • Family-owned, BBB Accredited since 2015, licensed, bonded and insured HVAC contractor. We also handle the Nicor rebate and Lennox promotion paperwork.

Other furnace brands we install

Not sure Lennox is the right fit? We are also a Carrier Factory Authorized Dealer. Compare Carrier prices below or ask us for a side-by-side quote.

Carrier gas furnace

Carrier furnace prices and installation cost

 Furnace installation

Furnace installation & replacement overview

Frequently asked questions

How much does a Lennox furnace cost installed in the Chicago suburbs?
In 2026, illustrative installed prices are Lennox Merit furnaces at $4,785 (ML180EK), Elite furnaces at $5,213.75 (EL280EK) and Dave Lennox Signature furnaces at $5,450 (SL280VK), with the modulating SLP99VK at $7,137.50. Website prices are budget guides before available rebates, not binding quotes. Every installation is custom; an in-home consultation is required for your final written estimate. Final cost may be lower or higher; eligible rebates may reduce it. A heating load calculation is required to size your furnace correctly.
What is the difference between a Lennox ML196E and ML196EK?
Lennox identifies the K furnace suffix as refrigerant detection-ready. Compare the exact model ratings and verify compatibility with the indoor coil, controls and required detection components before installation.
Is the Lennox SLP99VK worth it?
The SLP99V family offers variable-capacity heating and efficiency ratings up to 99% AFUE. The right choice depends on your heating load, comfort needs, installation requirements and budget. Actual energy use depends on the home and system operation; rebates require separate eligibility verification.
Which Lennox furnace qualifies for the 2026 Nicor Gas rebate?
Nicor Gas offers $150 for qualifying furnaces rated at least 95% AFUE and $225 for qualifying furnaces rated at least 97% AFUE. Efficiency alone does not establish eligibility: the customer, exact equipment, installation and application must meet program requirements. Qualifying equipment must be installed in 2026; apply within 90 days or by January 31, 2027, whichever comes first. Eligible furnace-and-thermostat bundles have separate requirements.
Do I need a new thermostat with a Lennox furnace?
Single-stage Merit and constant-torque Elite “E” furnaces work with any standard or Wi-Fi thermostat (ecobee, Nest, Honeywell). Variable-speed Elite “V” and Signature furnaces work with those too, but a Lennox iComfort® S40 unlocks communicating control, remote diagnostics and the finest staging. We include thermostat options in every quote.
How long does a Lennox furnace installation take?
Most straightforward replacements are done in one working day (4–8 hours). Converting from an 80% furnace to a high-efficiency condensing model adds PVC venting and a condensate drain and may run into a second day. Furnace-plus-AC replacements are typically one long day.
What warranty comes with a Lennox furnace?
Warranty coverage depends on the exact model, residential or other application, registration, jurisdiction and selected coverage option. Review the applicable Lennox warranty certificate and registration requirements. Any GSHA installation or workmanship coverage should be stated separately in your written agreement.
How quickly can you replace a failed Lennox furnace?
Replacement timing depends on the required model, size, equipment availability and installation scope. Call (224) 220-3660 or book online to confirm current availability and scheduling for your home.
Ready for a Lennox furnace quote?
Call now or book your free in-home estimate. We answer 24/7.

Last updated September 16, 2026 by the GSHA Services team. Website prices are budget guides before available rebates, not binding quotes. Every installation is custom; an in-home consultation is required for your final written estimate. Final cost may be lower or higher; eligible rebates may reduce it. A heating load calculation determines the right size for your home.