It seems that Harker's top priority is to get paid rather than to satisfy its customers, even when it is clear that work was done unprofessionally. The technicians are generally good, but the customer service people answering the phones are rude and even hostile - so if you have a problem that you need to discuss with customer service, you probably won?t be very successful finding a fair solution. If the lack of courtesy and support provided by the customer service people are a reflection of the customer satisfaction, then many customers must have had a similarly bad experience as I did. Our story begins in November 2008 when we got our thermostat replaced by Harker. Replacement work went fine, but about a month later, at 7 pm on a Sunday night, the furnace would not turn on - not exactly ideal considering that the low for the night was forecasted to be below zero. We called MG&E who came out immediately and determined that there was a problem with the thermostat. They told us that we should call Harker since the work that they did was probably still under warranty. Harker came out and diagnosed the problem as a short in the thermostat wire going from the thermostat to the furnace, and not the thermostat itself. My feeling at this time was that the short was in the thermostat and not the wire, but since they are the professionals, I thought they must know what they are doing, so we told them to go ahead and replace the wire for $213. However, within a couple of months it became clear that the problem was misdiagnosed after the thermostat began, again, to short out. After changing the settings on the thermostat when warmer weather arrived in the spring, the thermostat had to be turned on and off repeatedly in order to get the furnace to run. I called Harker and explained that the thermostat they installed was faulty and needed to be replaced. After the technician diagnosed a short in the thermostat, he replaced the thermostat with a new one. He told us the charges were $135 for the service. I told the technician that I was not going to pay for the service charges since the problem was misdiagnosed several months earlier when I had to pay $213 to replace the thermostat wire, which obviously did not actually needed to be replaced. To add insult to injury, I noticed that after the technician left, he installed the new thermostat off-center, so now we must have someone else come out and move it or paint the wall. I was sent invoices for the service charges, but after talking to the lady in customer service to explain why I did not think I should be charged again after the wrong diagnosis was made, her response was the labor is guarantied for 30 days. She did not care what I had to say and was unfriendly at best. I also told her the thermostat was installed incorrectly the second time, but she did not even take notice of this issue. She finally agreed to split the difference of $135 after a lot of hostility. So in the end, the new thermostat we had installed by Harker cost us $543 ($263 for the first thermostat, $213 for replacing the wire, and $68 ($135/2) for replacing the first thermostat). Update: Due to the strong recommendation of a friend and Harkers good customer ratings on Angies list, I gave Harker a second chance when we moved to our new home (they also installed the furnace in the home, which is also why I thought it would be good to call them). We needed someone to adjust the inline dampers in our 3-year old home to improve the airflow to a second story bedroom. The technician was extremely helpful, friendly, and responsive. He improved the airflow to the bedroom and gave good advise on how to keep the upstairs bedrooms cooler during very hot summer days. The people answering the phones also seemed much friendlier than they used to be, too (they no longer made me feel like I was bothering, or disturbing them with my call). I would rate this last experience with Harker very positively - it seems that Harker might have gotten the message after reading my last review and greatly improved their customer service.