At least once a week (and sometimes, every 1-2 days!), a customer will bring a water-damaged computer into the Service department. Unfortunately, it’s generally already too late to salvage the damage by the time it gets to us.
The components in a liquid-damaged laptop corrode rapidly, even when nearly-dry and with or without intervention. However, sometimes what ends up damaged will not inhibit the usability of the computer. Drying/cleaning may not even be strictly necessary at times, making the use of heating elements not worth the risk.
A common misconception is that heat will dry out the components without damaging the machine. Frequently Apple laptops will find their way into ovens or beneath hair dryers. These methods are going to melt the plastics and potentially cause heat damage in the machine. It’s tempting to do because it takes a long time for moisture to evaporate without extreme heat. However, in our experience, adding heat into the equation is never a good idea.
The best techniques, as I’m sure many of you have heard before, involve letting the hardware dry slowly, preferably in an environment where moisture will be leeched from the air, and not somewhere humid. The most common trick is to leave the laptop in a sealed plastic box or bag full of dry rice. This is also frequently used for wet iPhones and iPods.
As always, avoiding liquid damage is preferred by all. Leave drinks away from tables with machines on them, or keep them on a different surface nearby. Try bringing a plastic bag on rainy days just in case. But if the worst does occur, try not to panic. Remove the power/battery if you are able, and get the machine in rice ASAP.