lubricationrefrigeratorswitch
The water dispenser on my refrigerator sticks when you press it in. Sometimes it pops right out, and sometimes it stays in for 10-15 seconds. I've taken it apart a couple of times, cleaned it out, and tried spraying lithium grease and Liquid Wrench "Dry Lubricant" in there. Both work for a few weeks, then it starts sticking again, and gets worse over time.
The switch is a little plastic wedge that slides inside a plastic opening. Any tips?
Properly lubricating the hinges should stop the squeaks. In short, you remove the hinges from the door, lubricate them, and put them back.
You'll want to use white lithium grease. It works very well for metal on metal contact.
I'm assuming simple door hinges here, like these
You'll want to do each door one at time.
Long Process
Short Process
Do one door first, and give it few days to make sure the squeak is gone.
After reading @woodchips answer and throwing in my $0.02 offhand, I did a bit of research. I found this article on the use (or non-use) of graphite on aircraft. The article mentions that metals such as aluminum, magnesium, zinc, and cadmium may experience galvanic corrosion when exposed to graphite lubricant. Since galvanic corrosion requires an electrolyte, you might be okay if your metal components are inside, and not in a wet area.
The article also mentions that graphite can damage stainless steel at high temperatures. (Probably not going to be an issue in a home though. If it is, you may have other problems like a house fire, and probably won't care much about your hinges at the moment.)
Best Answer
If it's entirely a mechanical valve, then use food-safe silicone grease. If it still sticks, you can just replace it.
If it's an electrical switch that opens a solenoid on a water valve, then you should just replace the switch.
I've had really good luck getting replacement parts and advice from http://www.repairclinic.com