Is It Okay To Fill An Espresso Machine With Milk Instead Of Water?

Q: If I fill the water compartment of my Espresso machine with milk instead of water, will it clog/ruin the machine? I'm not talking about the frother, which is used to frothe milk. I'm talking about the water compartment that you put water in, which makes steam, which makes Espresso. Anyone who's ever owned an Espresso machine will know what I'm talking about. Any help would be really appreciated. Thanks!

A: Yikes! NO!!! Do not do that! The casein in the milk will definitely clog your expensive machine and you will have an awful and awfully expensive time repairing your machine. Can't you tell that simply by having to wipe off the steamer's nozzle with every use? How are you going to get the inside of the Espresso machine clean, after you've filled it with milk? The milk residue will sour in there, and bacteria will grow (and smell) ... not to mention that you're going to gunk up the machine. WHY would you want to do that? I'm assuming you don't have a high-quality machine, or you'd want to take good care of it. Don't do that if you ever want to use your Espresso machine again!