dell 1525 no direct stat up

I have a Inspiron 1525 laptop does not function when you adjust the power button until after the hot air heated from the bottom of the laptop for a short period
  These are the situation occurred because of increased moisture in the atmosphere of the room
This situation occurs now, even if left in laptops anywhere, especially if they do not gotta work for a day or less

How I can fix this trouble??

Thank you for help.......