Leith Heating and Cooling Inc. is a veteran-owned, family-run heating and cooling company based in Elgin, IL, serving the Fox Valley and nearby areas like South Elgin, Carpentersville, Dundee, Bartlett, St. Charles, Geneva, Algonquin, Huntley, and Lake in the Hills. Need AC repair, furnace repair, boiler repair, or heating repair near Elgin or the Fox Valley? Our technicians provide clear diagnostics, upfront communication, options, and quality workmanship for homes and businesses. We also offer HVAC installation and replacement, seasonal tune-ups, heat pumps, ductless mini-splits, thermostat service, ductwork, and indoor air quality solutions. 24/7 emergency service available, plus online estimates, financing, and service agreements.