Answer to: My phone overheated and won't turn on, what do I do?Remove the battery and check to see if it is deformed this can cause it to fail. if it is the battery replace and then evaluate from there.
Answer to: What to do when your HTC EVO 4G is exposed to water?Try putting it in a bag of rice. It will help absorb the water. But to prevent corrosion and short circuiting of the device disassembly and proper cleaning. I like to disassemble the device and put in a bag of rice for a couple hours just to make sure I got all the water out.