are you even using the end of the connection? Upon further review it looks like the left part of that picture there is a silver compression nut that is not connected to anything. Is that what where the dryer used to hook up? If it has a hole in the middle of it and the nut comes off then you can just hook a compression fitting to the end of that line in place of that silver nut you took off only this time stick a copper line through the middle of it and a valve. Connect the other end of your copper line to another compression fitting and then to the machine. Just match up the thread sizes to both this fitting and the machine. I should think a 1/4" copper line or even better, something high tech and flexible if there is such a thing. They have flexible water pipe that hold much more pressure then a gas line ever would. I just looked it up, gas lines in the home are typically .2 to .3 psi and in newer homes anywhere from 2 to 50 psi. I was just farting around with a high pressure aeroponic this past week that was working with pressures of upwards of 60psi. You do the math. A water leak at 60 psi is no more pleasant to work with then a gas leak would be. Only difference would be if a match was near by.