Grayson arrived promptly at the scheduled appointment time of 9 am. He was courteous and knowledgeable. We have a Trane, 2-stage furnace installed in December 2017 by another company (no longer in business). I appreciated that he took the time to explain what the maintenance involved and answered all of my questions. He completed the 21-point inspection, fixing the air leak in the filter box which caused a whistling sound when the furnace ran, ensured the 2-stage furnace was operating efficiently, and reattached the wire to enable the humidifier to work properly. He was efficient, polite, and pleasant to speak with about the furnace. He knew his stuff!