I have a Frigidaire Gallery Gas Dryer that ignites, heats for about 7 minutes, then gets cold. It is model #FDGR849GHSO and has been converted to propane. If I open the door before the initial 7 minutes are up, it will not heat back up when I close the door. I checked the lint trap and the dryer vent going outside; both seem to be clean and free of obstructions. However, I have not taken the dryer apart to look inside; I am not sure how to go about getting this one apart.