HELLO Can my heater go bad in the hot end? I get "failure to heat" messages. Not the bed, ran test, no problems. More or less isolated to hot end. Would watch temp rise to 200. Start out fine but after 120 would climb, then drop back cpl degrees. This would happen few times and never get higher than 170. SO CAN THAT LIL BARREL HEATER GO BAD AS I DESCRIBED??