Performed routine fall maintenance on Weatherking furnace in vista. Tested and verified correct operation of system and tested all safeties. Replaced air filter and made sure unit had good airflow. Recommend the following to keep system going long as possible 1. Adding sediment trap to system 2. Replacing hot surface igniter on system 3. Replacing transformer on system (Completed) 4. Adding SS2 switch for Drainline (Completed) 5. Replacing flame sensor 6. Upgrading thermostat