First: Check the handle sensor is welded Conversely, if the sensor is no problem (this is only the screen is generally 18 ℃ constant temperature constant, the actual tip temperature above 560 ℃ redness) and then check whether the six-pin socket five-pin socket weld Anti FET is burned, handle sensor welding reversed.
Secondly, if the screen temperature below 420 ℃ and above the actual temperature reached 560 ℃, in which case the tip redness usually handle no problem, usually FET and thyristor power tube and tip mismatch caused.