When my central A/C quit, their service tech said my thermostat was bad. He wanted another $200 to install a $30 thermostat on top of the $79 service charge. I told him that was a little steep and that I would replace the part myself. After successfully replacing the thermostat the A/C still did not work so I called a different company to diagnose the problem. As it turns out, The thermostat was not the problem.The DeAngelis tech had left an electrical plug disconnected under the cover on the A/C unit (intentionally?). I don't know if it was an accident or a scam, but it shouldn't have happened. His "mistake" cost me an unnecessary service call. When I called and spoke with the owner, I told him what his tech did and I felt his company was to blame. I politely asked him if he would simply share the cost of my second service call and pay half. He basically told me that he knew he already lost me as a customer so he wasn't going to give me a dime. DON"T TRUST DeAngelis Heating!