Ken arrived at the scheduled time for the bi-annual Carrier heat pump maintenance. He cleaned the furnace water filter, changed the two air filters, and thoroughly checked other components. He remembered, even though I had forgotten, that I had prepared for the work. Best Heating & Cooling is the best heating and air conditioning service that I've had in the 43 years that I have lived here. During the record cold spell a few weeks ago, my house stayed toasty warm. Thanks for the professionalism.