Performed annual ac maintenance on 16 yr gas package unit ground. Washed unit changed 14-25-1 filter. Checked refrigerant after unit stabilized. Found small dead frog behind circuit board. Removed. Board looks good no burn spots. Checked wiring all tight. Contactor a little worn, keep an eye on it. Fuses and disconnect ok. Blower motor a little dirty working at this time. Plenums for side shot to unit small, so recommend keeping filter clean so it doesn’t restrict airflow. 18 degree temp split.