THIS COMPANY PUT MY FAMILY'S LIFE IN DANGER. I would give negative stars if I could. This company did a "repair" on my furnace back in 2012 that was done incorrectly (under home warranty). Thankfully the fail safe worked over the years. Apparently the flame was turning on but the fan was not wired to turn on to blow heat so eventually the system would overheat and kill power as well as turn on the fan to cool the unit. I was feeling heat coming through the vents so I thought the system was working. This past summer I had NV Energy install a new thermostat. The installer never went into the attic (although Vern tried to implicate NV Energy as doing something wrong). When I switched to heat this winter, the unit would run for a few minutes then I would lose power to the thermostat. My initial thought was that there was an issue with the thermostat so I had NV Energy come back out to check it. They did. No issues with the tstat, told me to call a HVAC company. I was hesitant to call back to Windy City because of the many times they had to come out for the first "repair" (6+ times over a few weeks). I called another company, Air Zone Cooling and Heating, they took one look and told me the previous company "butchered" my system. In fact, they refused to work on my system because of the potential liability issue. They took pictures to show me what was done and talked me through what was happening and told me the danger I had been in. They turned off the gas and disconnected the electricity to not expose my family to more danger. They told me that the reason I didn't notice the issue prior to the new tstat was that the Windy City tstat is a battery operated unit so it always works as long as the battery is good. He explained to me that the NV Energy tstat works off the furnace low voltage and because the safety switch was tripping due to the system over heating and the tstat would lose power. So I called back to Windy City in the hopes that they would correct their mistake. Two visits later they told me they fixed the unit. I had them run through a cycle of the furnace with me and they did. I paid them almost $530 because they said the timing board was bad. Not trusting them I called the Air Zone back to make sure things were safe and Windy City was no longer putting my family in danger. He ran some diagnostics and determined that the repair was now done correctly and that the new wiring is what should have been done years ago. I showed him the invoice that I paid to Windy City and he was flabbergasted. He let me know that Windy City RIPPED ME OFF. He told me on his first visit, the first thing he checked was the timing board (because the fan wasn't turning on). He put in a brand new timing board and the fan never came on like it should. So replacing the timing card DID NOT REPAIR MY UNIT, IT WAS THE WIRING CHANGE that made the fan turn on. Windy City charged me for replacing a timing board that was not bad to cover up their mistake from years ago. And in the mean time charged me for replacing a board that was not bad. I called and emailed with Vern at Windy City in an effort to correct the situation. They refused to admit that they made any wiring changes, I even sent before and after pictures showing the change in wiring and the written reports from Air Zone. They were unwilling to budge and kept insisting that the timing board was bad. Vern offered a one year membership into their Premier Club for free in which they'll come check my unit twice a year. What a joke!!! There's no way I'll have this company near my house ever again. I will be working with my credit card company and small claims court, if necessary, to get my money back. If I can save someone the hassle, please stay away from this company.

They were horrible, the guy was a complete jerk didn't follow through on what he said that he was going to do didn't do what he said he going to do, tried to get more money out of me after I already agreed to, so I had to pay somebody else to finish the job that he started. They did a terrible job didn't finish the work we had to call them back after a few weeks to paint the frame of the air conditioning unit which they installed, they didn't paint it they left bare metal on the roof and they didn't put the condensation tube that was suppose to drain off the roof onto the ground they just left the condensation ripping right onto the roof to wreck my unit ridiculous I tell everybody don't use these people complete jerks.

Perfect gentleman that I would welcome in my house again!!

Well, he did not fix the problem and did nothing to get the ac working again.

Dishonest and incompetent
First problem, I paid for a arocool pro series evaporative cooler. What they attempted to install was a cheaper model with windy stickers placed over every factory marking identifying what the cooler truly was.  When I brought this obvious amateurish attempt at deception up to the owner I got indignant anger. On top of that they tried to install it in an area that due to county building code was unacceptable. A county building inspector caught the problem after they made a big hole in the side of the house.
Now I have a Rube Goldberg mess of ducting that the sun beats down on greatly reducing the effectiveness of this contraption.
Second problem, I was sold on a six zone A.C. system (very energy efficient). this system has never worked right. If one zone (the master bedroom or living room) is set to 72 the other zones are much colder, the other two bedroom's will be at 65 and the dining room will be at 67. During winter if the master or living room is at 72 than the others will be at 80+. 
 I have call them back to fix this problem, to get what they said they would provide, what I paid for but no joy.

They worked really well around my schedule. They had the best price and they were good. They did as well as the companies that wanted $10,000.

I am so happy I finally made the decision to replace my system. Windy City showed up at the time promised and the their employees were very knowledgeable and polite. The total time to install the unit was less than I expected and they also took extra care not to leave a mess. I would recommend Windy City to anyone who needs any air conditioning or heating work done.