Customer complained that the right back classroom did not seem to be the same temperature as the thermostat and was cooler. I inspected all 3 systems and only found extremely dirty filters. I also tested the temperatures in all classrooms and all were accurate. Customer also mentioned that corporate recently installed they’re own thermostats which have a schedule that’s specifically set for 68 degrees and will not go above 70 degrees. Systems are working properly, 2-18x20x1, 16x20x1. Pics uploaded Sending invoice to email for payment