Marengo, IL Heating & Cooling

Full-Service HVAC Contractor for Marengo, IL

Marengo is a city in McHenry County, and we reach it from our Elgin shop with the same trucks, parts and technicians that cover the rest of the Fox Valley. Furnace, air conditioner, heat pump and boiler repair, replacement and maintenance on every major brand, with the phone answered 24 hours a day.

Call (847) 224-2420
Book Online
  • Furnace, AC, heat pump and boiler
  • Nicor Gas Contractor Circle member
  • ComEd Heat Pump-Trained
  • 24/7 emergency service

One Contractor for the Whole System

Heating

Furnaces and Boilers

Gas furnace repair, replacement and tune-ups, plus hot-water and steam boiler service for radiator and baseboard homes.

Cooling

Air Conditioners and Heat Pumps

AC repair on any brand, R-32 replacements, and cold-climate inverter heat pumps that heat and cool from one unit.

No ducts

Ductless Mini-Splits

Daikin single and multi-zone systems for additions, bonus rooms and older homes that were never ducted.

Full-service means one call whether the furnace quit, the air conditioner is icing up or the boiler is banging. Owner Jeff Kerley holds EPA 608 Universal and NATE certifications in Air Conditioning Installation and Gas Heating Installation, and the team carries Daikin and Amana factory training. Reach us any hour at (847) 224-2420.

24/7 Emergency HVAC Service in Marengo

No heat below freezing, no cooling in a heat wave, or a boiler leaking on the basement floor: those do not wait for business hours, and neither do we. Check the thermostat, the breaker and the furnace door switch first; if that does not fix it, call (847) 224-2420 and we will quote the after-hours visit on the phone before we dispatch.

If you smell gas, leave the house right away, call 911 from outside, and call your gas utility’s emergency line from outside before calling us. See emergency furnace repair, emergency AC repair and emergency boiler repair for what counts as an emergency and what can wait until morning.

Furnace Repair and Replacement in Marengo

Furnaces here run hard from November through March against design temperatures near 0°F, and the first cold snap is when the weak ones fail. We repair every major brand. Igniters, flame sensors, pressure switches, inducer motors and control boards are the common failures, and most of those repairs typically land between about $150 and $900.

A cracked heat exchanger, or a repair bill past half the cost of a new unit on a furnace over 15 years old, is where furnace replacement makes more sense. A 95% or 97% AFUE condensing furnace qualifies for a Nicor Gas instant discount of $150 or $225, or $200 or $275 with a qualifying smart thermostat on the same invoice.

Cooling, Heat Pumps and Boilers

Humid summers

AC Repair and Replacement

Capacitors, contactors and fan motors commonly run $150–$700. Refrigerant leaks and compressors can run into the thousands, where the repair-or-replace conversation starts.

ComEd discounts

Heat Pump Installation

A qualifying ducted cold-climate heat pump such as the Amana S-Series gets $900–$2,000 off from ComEd, or pair it with a gas furnace as a dual-fuel system.

Hot-water & steam

Boiler Service

Cold radiators, kettling, pressure swings and lockouts repaired on any brand. Laars boilers installed, with $350 or $500 Nicor discounts on qualifying units.

R-410A is being phased down and its price is rising, so new cooling equipment uses R-32. See AC repair, AC replacement, heat pump installation, dual-fuel systems and boilers.

What a Service Call Costs in Marengo

Repairs start with a flat diagnostic fee to find the problem. During office hours (9 a.m. to 5 p.m., Monday through Friday) the service call is $130; weekday evenings after 5 p.m. it is $180, and nights, weekends and holidays are $260. Each includes 30 minutes of travel and 30 minutes of diagnostics, and parts are extra. Once we know what failed, you get a flat-rate repair price and approve it before any work starts. We file the permit where the municipality requires one.

After-hours and emergency service calls are priced higher than business-hours calls, and we quote that on the phone before we dispatch. Replacement quotes are free, written, sized from the house rather than the old nameplate, and include the discounts. Financing prequalifies in about 2 minutes with no impact to your credit score.

Marengo HVAC Services

Heating, cooling, boilers, ductless and indoor air quality for Marengo from one contractor. Each service below has its own page.

24/7 no heat

Furnace Repair in Marengo

No heat, short cycling or a furnace that clicks and never lights, diagnosed and repaired on any brand.

Nicor discounts

Furnace Replacement in Marengo

95% and 97% AFUE furnaces with the Nicor Gas discount taken off the invoice, quoted free and in writing.

All brands

AC Repair in Marengo

Capacitors, contactors, fan motors and refrigerant leaks on every major brand, priced before the work starts.

Free quotes

AC Replacement in Marengo

R-32 equipment, sized from the house, with a free written quote and the old unit hauled away.

ComEd discounts

Heat Pump Installation in Marengo

Cold-climate inverter heat pumps, including Amana S-Series, with $900–$2,000 off on qualifying ducted systems.

Hot-water & steam

Boiler Repair in Marengo

Cold radiators, banging, pressure problems and lockouts on hot-water and steam boilers of any brand.

No ductwork

Ductless Mini-Split Installation in Marengo

Daikin single and multi-zone systems for additions, bonus rooms and houses that were never ducted.

AprilAire

Indoor Air Quality in Marengo

Whole-home humidifiers, dehumidifiers and media air purifiers installed on your existing furnace or air handler.

Any hour

Emergency Furnace Repair in Marengo

No heat below freezing is an emergency. We answer around the clock and quote the after-hours call before we roll.

Any hour

Emergency AC Repair in Marengo

AC not cooling in a July heat wave, handled the same day whenever we can get there.

$240 / year

Maintenance Plan in Marengo

Spring and fall tune-ups on one system, plus one free business-hours service call and 5% off services.

Also available in Marengo: air handler repair, smart thermostat installation, humidifier installation, dehumidifier installation, air purifier installation, duct cleaning and airflow diagnostics and dual-fuel heat pump and furnace systems.

Rebates in Marengo

Marengo is served by ComEd and Nicor Gas, and both instant discounts are applied right on your invoice at installation: $900–$2,000 on a qualifying ducted heat pump, $500 or $1,000 on a qualifying ductless system, $225 on a furnace at 97%+ AFUE or $150 at 95% AFUE, and $350 on a qualifying 95% AFUE boiler or $500 on a combination boiler. There is no application and nothing to mail in.

See ComEd Instant Discounts and Nicor Gas Instant Discounts for the qualifying equipment, or ask for the numbers on your free quote.

Marengo HVAC FAQs

Do you really cover Marengo from Elgin?

Yes. Marengo is inside our McHenry County service area, and our technicians reach it from our Elgin shop for repairs, replacements, maintenance and 24/7 emergency calls.

Do I need a permit to replace a furnace or air conditioner in Marengo?

We file the permit where the municipality requires one and schedule the inspection as part of the installation, so there is nothing for you to chase.

Do ComEd and Nicor Gas discounts apply in Marengo?

Yes. Marengo is in ComEd and Nicor Gas territory, so both instant discounts come off the invoice at installation.

What does an after-hours call cost in Marengo?

After-hours and emergency service calls are priced higher than business-hours calls, and we quote the call on the phone before we dispatch. Repairs are flat-rate and approved by you before any work starts.

Do you work on boilers in Marengo?

Yes. We repair hot-water and steam boilers of any brand, install Laars boilers, and handle the radiators, baseboard and controls that go with them.

Do you service all brands, and how do I book?

Yes. We install Amana and Daikin and repair every major brand of furnace, air conditioner, heat pump, boiler and mini-split. Call (847) 224-2420 any hour, or book online and pick a time that works for you.

Other Towns We Serve

Don’t see your town? Call (847) 224-2420. View all service areas.

Your Marengo HVAC Team

Full-service heating and cooling for Marengo from a team based in Elgin.

Call (847) 224-2420
Book Online

Planning a replacement? Request a free quote or see financing options.

Discount amounts reflect the 2026 Nicor Gas Energy Efficiency Program for qualifying equipment installed January 1 through December 31, 2026, and are subject to change or cancellation due to funding limits. Rest Assured HVAC LLC is an independent contractor and is not affiliated with or endorsed by Nicor Gas.

Discount amounts reflect the 2026 ComEd Energy Efficiency Program for qualifying equipment and are subject to change or cancellation due to funding limits. Rest Assured HVAC LLC is an independent contractor and is not affiliated with or endorsed by ComEd.