1）Disconnect the power plug, wait unit the desoldering gun temperature down to room temperature.

2）Loosen screws and disassemble desoldering gun.

3）Cut off the wire of heating element, prepare a new heating element (model no. 5SS-331N-H).as follow figure.

4）Connect heating element：

Put the heating element on the black heating element holder, insert the heat shrink tube（Φ3x25mm）and metal tube (Φ2x6mm) to the wire, connect wire and pull the metal tube to the connect position, crimping the metal tube with crimper tool, pull the heat shrink tub to the metal tube and heating.

-- Long blue wire (ground) connects to the yellow wire in handle

-- Two white wires (heating element) connect to the two red wire, no need to distinguish positive electrode and negative electrode.

-- Two blue wires (Sensor) connect to the black and blue wire in handle, no need to distinguish positive electrode and negative electrode.

-- Any one wire connect to the Sleep control sensor

5）Measure the resistance value again, make sure the value is correct. Short the desoldering gun nozzle and shell of plug, and the resistance value should be 0Ω.

6）Assembly desoldering gun again, do not press the wire or put into the wrong position.