I have a contract with Flanders Heating & Air Conditioning to do maintenance work on my furnace. They recently came out and did a maintenance check on my system. It was working fine until they did maintenance and then it would not work at all. I called them back and they came back out and got it going again. The first serviceman did not seem to know what he was doing. The second serviceman was very knowledgeable. I had a similar experience last year when they did the maintenance check. I will continue to use them because I have a contract with them but I may look around when the contract ends.