Goodman GMP100-5 RevB
Horizontal, supply terminating on left side.
I checked everything I can think of to check. No obstructions blocking airflow. I even pulled off plenums and still tripping. Limit is good. Temp gets to 240 in about 5 minutes.Gas pressure was at 3"wc so I can't turn it up cause it will trip quicker. No obstructions in flue. I pulled that off too and still tripping. I ran combustion test and nothing out of ordinary. It still runs at 81% efficiency before it trips. I pulled blower out and everything was clear. I could see all the way through. Blower cap and motor okay. I calculated cfm at 1851 cfm with a 40 degree heat rise. I tried to run in all different speeds and still tripped.The unit is only getting super hot where the limit is. Normal temps at top and bottom of heat exchangers. Never ran into this problem..suggestions are kindly welcomed cause I'm pulling my hair out on this one.
Ray in Texas