I have been using Windy City Air Conditioning & Heating for at least 5 years. They come to my house twice a year to do the scheduled maintenance on my air conditioner and heater. If I ever have a problem I just call them up and they send someone right over to take care of it. I have never, in those 5 years, had any type of problem with the company. They are great. I would give them 10 stars if I could. I highly recommend them.