Problems and repairs of electric soldering iron not heating
(1) If the electric soldering iron does not heat up, the first step is to correctly install the electric soldering iron heating core
After some internal heating electric soldering irons are replaced with new soldering iron cores, the temperature will not go up for a long time when the power is turned on. It can't even melt tin, and the handle is very hot. When checking, if the voltage is normal, you need to remove the soldering iron core to check whether the internal installation is reasonable. Because the inner heating type soldering iron core is the same length as the outer tube shell, the correct installation method is to keep the end of the soldering iron core aligned with the end of the outer tube instead of indenting or protruding. If the soldering iron core is retracted a lot, the installation of the electric heating core tends to the handle, which makes the heat concentrated on the handle end, and the heat on the soldering iron tip cannot reach the temperature of melting tin.
(2) Pay attention to the wiring of the new soldering iron core if the soldering iron does not heat up
The author had an internal heating type electric soldering iron core that was blown out, and the service life was not long even after replacing several soldering iron cores. After careful observation and analysis, it was found that the lead wire of the newly replaced soldering iron core was too short. There is no room for the soldering iron core to expand and contract when it is cold and hot, so that the internal thin resistance wire is broken when the soldering iron core is cold and shrinks after the plug is unplugged. The correct replacement method should be to make the lead wire a little longer, 1-2mm, so that it is not easy to burn out. But at the same time, it should be prevented that the wire end is too long to cause wire touching and short circuit faults.
(3) If the electric soldering iron does not heat up, it is not suitable to use the twisting method to repair the broken heating wire
After the hot wire or root lead of the electric soldering iron is disconnected, it is generally reconnected by twisting method. This method often causes ignition or thermal fuse due to loose contacts and high contact resistance. A more subtle method is to take out the heating wire, first remove the oxide at the joint, and then twist it tightly. Then put a little broken glass and electric porcelain (6:1) powder around the joint. After installing it, turn it on for a few minutes, and the powder will melt and attach to the contacts, making it less likely to fuse and more durable.
