Windy City Air Conditioning & Heating came out recently to do some maintenance work, along with a minor repair, on our heating unit. They came out as scheduled and everything went smoothly. We've used them before since we have a service contract with them. During our first interaction with Windy City, we were having some problems with our air conditioner. They were the only company with a 24-hour answering service, so having someone physically pick up the phone and answer our call was a big deal to us. They came out and provided us with some emergency service, and we've been with them since then. We just renewed our contract with Windy City, so we will definitely be using them again.