Problems about cascada.

We have a client meet problems with his old spray gun now. He bought our powder coating machine COLO-600 in two year ago, recently he said his gun have problems, he can not adjust the voltage , so we thought because of the problem of cascada. 

But when received the new casada sitll have probelm. first we need to clean the guy body, second we can change this cascada in other gun to test if it is problem really from cascada. 

We are not afriad the problems, we just want to know where is problem!