Performed furnace clean and tune; started by inspecting the exhaust and intake pvc ensuring all connections were secured, I then removed and cleaned burners along with the flame sensor, Next I cleared out the drain line and removed a section of line for better pitch, I then cycled the system on and checked gas pressures, lastly I performed a combustion test verifying no CO in the airstream as well as replaced the 16x25x1 filter. This system is currently operating normal and heating at 52 degrees at this time job complete.