Sign up 1 comfort club membership and complete 1 system furnace repair and preventative maintenance check. Find system have burnt fuse due to short on thermostat common. Remove the common wire from tstat and operating with battery. The system not operating due to miss fire. Complete combustion calibration and reduce co level. Replace flame sensor. System operating at this time. Change filter 20x25x1. Need to check on a starter kit for ac unit in the spring visit. Not yet collect for repair. We need to call the customer 4:30 pm on 12/02/2020 to collect for repair. Customer was not present to sign the invoice. Customer approved repair over the phone.