One of the largest misconceptions of hot melt packaging machinery is that maintenance on a glue applicator gun means replacing the entire assembly. That is not always the case. While sometimes, glue guns do need to be replaced, there are other times when a module or nozzle could be a cheaper solution to your problem.

What’s the difference?

It is pretty simple. The glue gun is the entire assembly (minus the nozzle). This includes the cordset, heating element, RTD, manifold and module. Essentially, if you order a glue gun, once you receive it the only thing you need to do is plug it in, attach the in-line filter assembly though the back fitting, screw on a nozzle and you are good to go. The reason to replace the entire gun would be if you get an error code on your melter main board that the gun zone is either not heating or not reading the RTD. If you get the gun zone heater error, that means that the heating element has stopped working and the gun needs to be replaced. If you get the gun zone RTD error, that means that the temperature can no longer be regulated and the gun needs to be replaced.

However, if you get no main board error code, but your gun is dripping or not dispensing glue at all, that could be a module or nozzle issue.

Modules are the mechanisms that attach to the front of the glue gun manifold to dispense the glue. These modules are operated by air and springs within the module body that control the piston to dispense the glue for easy release and clean cut off. If you are experiencing dripping, or no clean glue cut off, then most likely there is char in the spring that is holding the piston up and leaving the module open. Or, in some cases, the seals within the module could be stiff from usage and wear, and no longer creating the tight seal required for precision dispensing. In either of these instances, the module would need to be replaced.

If you are getting no glue at all to come out of the module, most likely your nozzle is clogged. The nozzle, or tip, is typically attached to the module and can easily be changed by screwing it off and on. In some cases, such as zero cavity or reduced cavity modules, the nozzle is fixed and can only be replaced by rebuilding the entire module, replacing the tip, piston and seals.

If you have any questions about which part of your glue gun you need to replace, please give us a call at 561-272-5442 or email sales@ussefl.com.