Today we came out for the main level not heating on Goodman 60k natural gas 80% furnace 2010 with 2008 matching 2 ton ac. Cycled equipment from thermostat found high limit switch open. Performed safety inspection with digital camera found severe metal fatigue and hot spots due to age and run time. Heat exchanger is compromised and could fail at anytime. In addition found weak ignition system and gas pressure too high. Due to equipment being at full life expectancy a long term solution is gonna be to update will schedule install supervisor to give options on updating. Bumped down gas pressure and gave bandaid repair options left all equipment in service all though equipment could fail at anytime. Based on our findings today, it might be time to think about getting a brand new system.