Lennox Premier Dealer Serving Will County, IL

Communities we serve in Will County

GSHA’s published service-area ZIP list includes these Will County communities: Joliet, the county seat, whose city limits also reach into Kendall County; New Lenox, Crest Hill and Romeoville, which lie entirely within Will County; Plainfield, partly in Kendall County; Bolingbrook, shared with DuPage County; and Channahon, which extends into Grundy County. Four more listed communities sit mostly outside Will County but include Will County neighborhoods: Naperville (mostly DuPage County, and served by the city’s own electric utility rather than ComEd), Aurora (mostly DuPage, Kane and Kendall counties), Lemont (mostly Cook County, also DuPage) and Tinley Park (mostly Cook County). In a cross-county town the building department and the electric utility depend on which side of the line your house sits on, and GSHA sorts that out during the estimate.

Lockport, Frankfort and Crete are not on the published ZIP list, although GSHA crews have recently worked in Frankfort and Crete; if you live in Lockport, in Frankfort or Crete, or elsewhere in southern Will County, please confirm your address at (224) 220-3660 or through the estimate form before scheduling. The complete ZIP-code list is on the GSHA service area page.

Lennox equipment guidance for Will County homes

Furnaces first, because the county runs on gas. Lennox’s current gas furnaces range from the Merit Series ML180EK (up to 80% AFUE, single-stage) to condensing models such as the Elite Series EL297VK (up to 97% AFUE, two-stage, variable-speed blower) and the Dave Lennox Signature Collection SLP99VK (up to 99% AFUE, modulating). AFUE is the share of the fuel’s energy that becomes heat in your home over a season, and Nicor Gas’s 2026 furnace rebates apply only at 95% AFUE and above, with a higher tier at 97% and above. In a 1990s house with a non-condensing furnace and a metal flue, a condensing model means new plastic venting and a condensate drain, which GSHA plans before filing the permit; New Lenox requires any venting change to be described on the application.

Heat pumps and dual fuel. A dual-fuel system pairs a Lennox heat pump with the gas furnace: the heat pump cools in summer and heats on electricity in mild weather, and the furnace takes over when temperatures drop. The Elite Series EL21KLV cold-climate heat pump is rated up to 20.50 SEER2 and 10.00 HSPF2, and the Signature Collection SL22KLV cold-climate heat pump up to 21.10 SEER2 and 10.50 HSPF2 (ENERGY STAR Most Efficient Cold Climate 2025). SEER2 measures cooling efficiency and HSPF2 heating efficiency; both are “up to” ratings for a matched system, and the rating your system actually earns depends on the indoor unit. For the roughly one in ten Will County homes heated with propane or electricity, a heat pump is the first thing to price, because ComEd lists incentives for ducted and ductless heat pumps (eligibility rules apply) while Nicor’s furnace rebates do not reach those homes. Straight cooling for a gas-furnace home runs from the Merit Series ML17KC2 (up to 18.00 SEER2, two-stage) through the Elite Series EL22KCV (up to 22.50 SEER2, variable-capacity) to the SL25KCV (up to 25.10 SEER2).

Mini-splits for rooms the ducts never reached. Bonus rooms over garages, finished basements, sunrooms and additions are usually the spaces the original ductwork serves worst. Lennox mini-splits Powered by Samsung handle them without new ducts: the MWLD single-zone cold-climate model is rated up to 25.00 SEER2 and 11.00 HSPF2, and the MMLD multi-zone model (up to 23.00 SEER2 and 10.50 HSPF2) runs several wall, floor console, cassette or slim-ducted indoor heads from one outdoor unit. A house anywhere in the county with no ductwork at all is a candidate for a multi-zone system as the primary heating and cooling; GSHA places the outdoor unit under the same yard rules the towns apply to a central air condenser (Plainfield’s ordinance covers air conditioning equipment generally; Lockport’s table names condensers and leaves similar equipment to the Zoning Administrator).

Thermostats and indoor air, in plain terms. Compatibility is set by the equipment: the Lennox S40 works with premium Lennox communicating equipment only and includes a dual-fuel function that alternates between gas and electric heat; the E40 handles two-stage systems; and the Merit Series M40 works with multi-stage non-communicating equipment. New Lenox requires a programmable thermostat with any furnace installation, and both Nicor Gas and ComEd list smart-thermostat rebates, so GSHA specifies the thermostat with the furnace. On indoor air quality, the plain facts: the Healthy Climate Carbon Clean 16 media air cleaner is MERV 16 and, in lab tests, removes up to 99.99% of particles down to 3 microns and up to 95% down to 0.3 microns; Healthy Climate whole-home dehumidifiers remove 80, 100 or 130 pints per day in muggy summers; a humidifier adds moisture when gas heat dries the house in winter; and an ERV or HRV brings in outdoor air while recovering up to 75% or up to 82% of the energy. GSHA describes what each device does to the air; we make no health claims.

Permits, utilities and installation considerations

In Will County the contractor pulls the permit and the municipality inspects the work; GSHA handles the application, spec sheets, contractor registration and inspections. Here is what the municipalities we checked publish.

• Village of New Lenox. The Miscellaneous Permits Guide requires a permit for air conditioning units and furnaces, submitted with the manufacturer’s specifications, whether the unit is a direct replacement or a high-efficiency upgrade, and any change to the venting. It also requires a programmable thermostat with a furnace, liquid-tight flexible metallic conduit outdoors, a breaker no larger than the condenser label allows and a final inspection; allow three to five working days, and an emergency installation still needs the application filed the next business day. Contractors must register with the village; Building Department (815) 462-6490.
• City of Lockport. The building permit FAQ requires permits for mechanical-system replacements, treats HVAC as an over-the-counter permit and makes the property owner responsible for seeing that one is obtained; contractors register with the Building Department first. The HVAC Replacement application asks for spec sheets, a plat of survey showing any outdoor unit and wiring by a licensed electrician, submitted in person or to building@lockport.org (Building Services, (815) 838-0549). Zoning Table 156.023 allows a condenser in a corner side, interior side or rear yard, not the required front yard.
• City of Joliet. The building code page covers mechanical and electrical changes, lists HVAC inspections after completion and requires contractor registration, a Certificate of Insurance, a per-project Letter of Intent and a Joliet-accepted HVAC contractor license. The contractor, not the homeowner, must pull the permit; applications go to permitapplication@joliet.gov or City Hall, and permits are not issued over the counter (residential permit information). The residential forms list no furnace-specific application, so GSHA confirms the current form with the Building & Inspectional Services Division, (815) 724-4070.
• Village of Plainfield. Permits go through the Permitting & Licensing Portal, and the building codes page lists the adopted mechanical, fuel gas and electrical codes. The pages do not spell out the furnace and air-conditioner replacement rule, so GSHA confirms it with the Building Department, (815) 439-2937. Zoning Sec. 9-14, Table II-2 permits air conditioning equipment only in rear, side and corner side yards at least four feet from all property lines, never in the front yard, and the noise regulations (Sec. 6-232) limit residential sound at the property line to 55 dBA from 7 a.m. to 7 p.m. and 50 dBA overnight, so on a small lot GSHA weighs the distance to the lot line against the outdoor unit’s published sound rating (Lennox rates the SL25KCV at as low as 58 dB, a manufacturer rating for the unit, not a measurement at your lot line).
• Unincorporated Will County. The Land Use Department Building Section permits through its SmartGov portal. Building Ordinance Sec. 150.003 requires a permit in advance for heating equipment and electrical installations, with an emergency-repair exception if the permit is applied for the next business day, and every contractor must be registered with the county. Contact (815) 727-8634 or building@willcountylanduse.com.
• Other municipalities (Bolingbrook, Romeoville, Crest Hill, Channahon, Naperville, Aurora, Lemont, Tinley Park) have their own building departments; GSHA confirms the requirement for your address before scheduling.

Utilities and rebates. Nicor Gas’s service territory names Will County communities including Aurora, Bolingbrook, Channahon, Crest Hill, Frankfort, Crete and Joliet, and New Lenox, Lockport and Plainfield name Nicor Gas on their own resident pages; a ZIP lookup on nicorgas.com is the definitive check. ComEd delivers electricity in New Lenox, Lockport, Plainfield and Joliet, but most of Naperville, including its Will County portion, is served by the city’s municipally owned Electric Utility, so ComEd programs do not apply to Naperville Electric customers. Nicor Gas’s 2026 residential rebates are for Nicor customers, require professional installation during 2026 and a claim within 90 days of installation or by January 31, 2027; they list furnace tiers at 95% and 97% AFUE, a larger amount when a smart thermostat is submitted on the same application, and no air conditioner or heat pump rebate. ComEd’s heating and cooling discounts cover ducted, ductless and geothermal heat pumps and its appliance rebates include ENERGY STAR smart thermostats; eligibility requirements apply and offers change. Check current eligibility with Nicor Gas and ComEd, and GSHA will say which quoted equipment qualifies.

Gas, electrical and what GSHA handles. A condensing furnace needs a gas line sized for its input and a condensate drain; GSHA sizes and runs the piping, and meter-capacity questions go to Nicor Gas. A heat pump, air conditioner or mini-split needs its own circuit sized to the manufacturer’s label and an outdoor disconnect; Lockport requires a licensed electrician for the wiring, and GSHA’s own licensed electricians do that work on every job. GSHA files the permit with the spec sheets and any plat of survey, meets the inspector, commissions the equipment, walks you through it and registers the Lennox warranty.

Recent GSHA work in Will County

GSHA crews have recently worked in Joliet, Romeoville, Crest Hill and Channahon, and in Frankfort and Crete in the southern part of the county, where we ask homeowners to confirm coverage for their address before booking.

More Lennox pages

Lennox Premier Dealer in Northern Illinois (main page) · Lennox furnaces · Lennox air conditioners · Lennox heat pumps · Lennox mini-splits · Lennox thermostats

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