Before doing this you will need to remove the panels from your machines. Unplug the machine and allow it to fully cool off.
Tools required:
Adjustable wrench x2
Locking pliers (aka Vise Grips)
Zip tie
NOTE: It is important to firmly hold the vacuum breaker / safety valve as steady as possible while unscrewing this fitting during disassembly or when re-installing this fitting when installing the new valve. Failure to do so will result in damage to the machine's plumbing.
NOTE: At this point, the valve can be removed and a new one installed. If installing a new valve you will need to remove the elbow fitting from the old valve and put it on the new one.