So, joemar4, to clarify:

This install did, in fact, require fuses, and somebody (previously) had deliberately eliminated them?

Even if the fuses were not required, obviously copper tubing is not listed for such a use.

Does "dummy" refer to the fuses, or...never mind...

P. S. Under the voltages/amps in this case, would said copper tubing act as a fuse or would it survive a short?

P. P. S. Is the tubing the same as what appears at the bottom-left of the top photo?