So for the past few months I have been printing in my Ender 3 and everything ran smoothly. But suddenly a few days ago I tried to print and the hot end temperature just keeps on rising past the set temperature of 230. I tried PID tuning, changing the nozzle, hot rod, and the thermistor nothing seems to work.... I even took out the main board and check whether the solder joints are loose, none so far. Any ideas on how to fix the problem?