I have Amana electric dryer, purchased in 2009. Worked great until last October, had no heat. Would start, drum spun and would complete time cycle, just not dry clothes. Investigated and found 240v heater relay on control board melted and smelled burnt. While I had it apart, I checked all components, including thermostats, thermistors, heater element, door switch, sensor. everything was okay. Unit ran for 6 months and last week found same problem, heater relay burned and melted, first inch of wire connected to relay burnt. Appliance pros warranteed the control board and I reinstalled. It ran for 5 loads on sensor dry, first load on time dry caused heater relay to burn up. All components are within spec, there are no shorts. What am I missing? Please help.

Thanks for the input, heater is not shorted to ground. I have 9.7 ohms resistance. Input voltage is solid 242 v. No drop during 5 min run. All connections are tight at panel, receptacle and block.
Question back to you, how much resistance should a 6' dryer cord have? Prongs to lugs vary from 0.1- 0.3 ohms. Is it possible the dryer cord is bad?