Troubleshooting a Model 7700

Our Model 7700 soldering irons are known for lasting a long time, but after enough years of use they might need some maintenance. Luckily, our irons are easy to service and troubleshooting a model 7700 doesn’t take much time! This guide will give you some ideas on what might be the issue with your iron.


The most common cause of problems is the battery. After around 10 years of use, the battery can get too corroded to work properly. Eventually, it will stop taking a charge altogether. To check this, simply open your iron up and see if you notice any corrosion on the battery. If you do, it’s probably time for a new one. Fortunately, this is an easy problem to solve. All you will need is a replacement battery to get your iron up and running again.

7733 Replacement Soldering Iron Battery

A replacement battery for a 7700


This is a less common problem, but we have seen cases where a transformer goes bad. If you have a voltage tester, see what the output of the charger is. It should be around 1.7VDC. If it’s low or nonexistent, then you’ll need a new transformer. Like the battery, the transformer is also easy to replace. You can find them here.

Other Issues

If the issue isn’t with the transformer or the battery, then you may want to send it in so we can take a look at it. The fusible link might have have been fried, or any number of other random things. You can find the 7700 rebuild program here. We’ll replace any parts that aren’t working and test the iron and charger.

Hopefully this guide has helped you with troubleshooting a model 7700. Have any tips for how to prolong the life of your iron? Be sure to contact us.