I had just started running whole-house AC this season, and noticed that it was not cooling the house like it should. A quick check showed that the evaporator coils (inside the furnace/AC) were freezing up soon after I turned on the AC. As usual, I scoured the internet for troubleshooting tips and learned that it was probably either dirty and clogged evaporator coils or low refrigerant. I’m a DIY guy, but this was beyond my skills. So I called up Superior MSI the next morning, and got an appointment later that day–nice! A service guy named O.T. came out as scheduled and we looked at the system together. I had a lot of questions and he answered them very knowledgeably and professionally. Obviously, the evaporator clearly never been opened, because to get at the inside of the evaporator, he had to cut a triangular sheet metal panel in half (which he later repaired with metal tape). I would never have thought to do that, but now I’ll be able to open it and clean it myself. Inside, we saw that the coils were almost totally blocked by a felt-like coating of dust that had restricted the air flow. O.T. peeled this stuff peeled off pretty easily, and then cleaned the coils with solvent. Next, we went outside and he hooked up some gauges to the compressor to check the refrigerant level, which was low. We had a nice discussion about temperature differentials and refrigerant levels as he topped off the refrigerant. Finally, O.T. told me what kind of filter to use in the furnace, since I had been using the wrong size and type. So, now the AC is working great–better than it ever has–and I’m looking forward to the coolest summer that I’ve had in a long time! I think the AC has been under-performing for a few years now due to years of neglect. Thanks to Superior Mechanical Services for a job well done by their professional, courteous and knowledgeable technician. I highly recommend them for any of your heating or cooling needs.