Lennox Premier Dealer Serving McHenry County, IL

Communities we serve in McHenry County

GSHA’s published service area covers these McHenry County communities by ZIP code: Woodstock, home of our headquarters; Crystal Lake, the county’s largest municipality; the City of McHenry; and Cary, Harvard, Lake in the Hills, Marengo, Spring Grove and Wonder Lake. Four more straddle a county line and also appear on our neighboring county pages: Algonquin and Huntley extend into Kane County, and Fox Lake and Island Lake lie in both Lake and McHenry counties; part of Cary is also in Cuba Township, Lake County. The village or city, not the county line, decides which building department issues the permit.

Johnsburg and Bull Valley are not on the ZIP-code list although our crews have recently worked in both, so if you live there or in unincorporated McHenry County, confirm your address with us first. The full ZIP-code list is on our service area page.

Lennox equipment guidance for McHenry County homes

With about 85 percent of county homes on utility gas, the typical replacement is a gas furnace matched with an air conditioner or heat pump, and the furnace’s AFUE rating matters because Nicor Gas’s 2026 rebates are tiered at 95 and 97 percent AFUE. The Dave Lennox Signature Collection SLP99VK is rated up to 99% AFUE with modulating heat, the Elite EL297VK up to 97% AFUE with two-stage heat and a variable-speed blower, and the Merit ML296VK up to 96% AFUE; 80 percent models such as the EL280EK (up to 80% AFUE) fall outside the rebate, and Lennox lists all four as dual-fuel capable. Cooling ratings are matched-system ratings: the Elite EL22KCV air conditioner (up to 22.50 SEER2) reaches its rated efficiency only with a specific indoor coil and blower, so we quote the pair we propose.

The county’s roughly 3,000 propane homes and 13,800 electrically heated homes are where a heat pump changes the picture most; the Census does not say where they are, so the test is a propane tank in the yard or electric heat inside. A Lennox cold-climate heat pump such as the SL22KLV (up to 21.10 SEER2 and 10.50 HSPF2, ENERGY STAR Most Efficient Cold Climate 2025) handles heating in milder weather and, in a dual-fuel setup, hands off to a gas or propane furnace at a switchover the load calculation sets against Woodstock’s 0 F winter design temperature. Gas homes can replace a worn-out air conditioner with a heat pump the same way; Nicor Gas lists no heat-pump rebate, while ComEd’s Home Heating & Cooling Discounts cover ducted, ductless and geothermal heat pumps.

With a 1989 median build year, many houses have a finished basement, bonus room or addition the original ducts never reached; a Lennox mini-split, Powered by Samsung, gives that space its own heating and cooling, and the single-zone MWLD cold-climate model (up to 25.00 SEER2 and 11.00 HSPF2) also suits older county homes that were never ducted. Thermostat choice follows the equipment: the Lennox S40 works with premium Lennox communicating equipment only and includes a dual-fuel control, the M40 works with multi-stage non-communicating equipment, and the E40 is rated for three heating and two cooling stages on a heat pump (two and two on a conventional system). Nicor’s 2026 thermostat rebate requires an ENERGY STAR certified smart thermostat on a natural gas system with working Wi-Fi, so we confirm certification for the model we propose.

Indoor air quality here is mostly winter dryness, summer basement humidity and duct dust. The Healthy Climate Carbon Clean 16 media air cleaner uses a MERV 16 filter that Lennox rates, in lab tests, at up to 99.99 percent of particles down to 3 microns and up to 95 percent down to 0.3 microns; the HCWB17 bypass humidifier provides up to 17 gallons of moisture per day, and Healthy Climate whole-home dehumidifiers remove 80, 100 or 130 pints per day. These are comfort and equipment-care measures, not health treatments.

Permits, utilities and installation considerations

Permits and inspections

Every furnace, air conditioner or heat pump replacement here needs a permit and inspection, which GSHA pulls and schedules. The rules differ by municipality:

• Woodstock. The city’s Building Permit Information page lists “Furnace, new or replacement” and new central air conditioning as permit projects; applications go through the OpenGov portal. The city says express permits generally issue in 3 to 5 business days and other permits take 10 to 15; we confirm which applies to your job. Inspections need 48 hours’ notice, under a city code that adopts the 2020 International Residential Code with local amendments.
• Crystal Lake. The permit page lists “HVAC and Air Conditioning” among required residential permits, takes applications through the 24/7 “ez APP” system, and processes residential applications within 10 working days or less.
• City of McHenry. The Building Permits page classes Furnace/AC as a counter-based permit, issued at application in person or within 24 hours online once the fee is paid, with 24-hour notice for inspections; the codes page lists the 2015 IRC, IMC and IFGC, the 2024 IECC and the 2014 NEC with amendments.
• Unincorporated McHenry County. Addresses outside any village or city go through the county’s Building Division (2021 ICC codes and 2020 NEC), which issues furnace/air permits over the counter, applies a stormwater review to most permits and takes applications through its SmartGov portal (Permit FAQs, Permit Resources).

Addresses inside any other village or city, such as Cary, Huntley or Harvard, go through that municipality’s own building department, as the county Building Division page directs; we file with whichever department covers your address.

Where the outdoor unit can go

We check the plat of survey against the local rule first. Crystal Lake (UDO Section 3-300): central air units at least 15 feet from a neighboring residential dwelling, discharging upward, never in the required front yard, which on Crystal Lake waterfront lots is the water side. City of McHenry (Section 11-14-4): mechanical equipment only in rear and interior side yards, never between the front or corner side lot line and the house. Woodstock (UDO Chapter 7A): accessory mechanical equipment at least 1 foot from a side or rear lot line. Unincorporated county (Table 16.60-1): no more than 3 feet into a side or rear setback, never the front setback, and never a recorded easement without the easement holder’s written permission.

Of the codes we reviewed (Woodstock, the City of McHenry and unincorporated McHenry County), only Woodstock publishes decibel limits, and its noise code exempts HVAC equipment at a single-family detached home when it is in good repair and operating within the manufacturer’s specifications; the City of McHenry’s noise code and the county’s nuisance noise ordinance use nuisance standards without decibel numbers. Lennox rates the SL25KCV air conditioner as low as 58 dB and the EL18KSLV heat pump as low as 54 dB, and we keep the unit away from a neighbor’s bedroom windows where the lot allows.

Utilities and rebates

Nicor Gas’s tariff names McHenry County cities and villages including Woodstock, Crystal Lake, McHenry, Algonquin, Cary, Harvard, Huntley, Lake in the Hills, Marengo, Spring Grove and Wonder Lake, plus unincorporated territory; check your ZIP with its service area tool, which notes that areas within a ZIP code may vary. ComEd delivers electricity, and no municipal electric utility was identified in McHenry County; propane homes buy from private suppliers. Nicor’s 2026 residential rebates for current residential customers are tiered at 95 and 97 percent AFUE for furnaces and include a smart-thermostat rebate (ENERGY STAR certified, on a natural gas system with working Wi-Fi, one per household); install in 2026 and claim at apply.nicorgasrebates.com within 90 days or by January 31, 2027. ComEd’s Home Heating & Cooling Discounts cover ducted, ductless mini-split and geothermal heat pumps, heat pump water heaters and ENERGY STAR certified smart thermostats, with eligibility requirements and offers that can change; its 2026 appliance rebate application requires a current ComEd residential delivery customer and a claim within 60 days of purchase or by February 28, 2027. Check current eligibility with ComEd and Nicor Gas; GSHA supplies the model numbers, ratings and invoice the applications ask for.

Gas, venting and electrical work

Moving from an 80 percent furnace to a condensing model means new PVC venting and a condensate drain, and a water heater left alone on a masonry chimney is checked for a liner, which we price in the estimate if needed. A heat pump may need a new disconnect, circuit or panel upgrade, done by GSHA’s own licensed electricians under the same permit; we also handle gas meter, regulator and piping changes, including propane lines. Well and septic are outside the HVAC permit, but we review the condensate drain route on site.

Recent GSHA work in McHenry County

GSHA crews have recently worked in Woodstock, Crystal Lake, McHenry, Huntley, Algonquin, Cary, Wonder Lake, Spring Grove, Marengo and Harvard, and also in Johnsburg and Bull Valley, which are outside the published ZIP list, so homeowners there should confirm their address with us first.

More Lennox pages

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

Other counties

• Lake County, ILLake Bluff office
• Kane County, ILserved from Woodstock and Lake Bluff
• DuPage County, ILserved from Woodstock and Lake Bluff
• Cook County, ILserved from Woodstock and Lake Bluff
• Will County, ILserved from Woodstock and Lake Bluff