How to Repair a Water or Liquid Damaged PCB

Printed Circuit Boards (pcbs) that are subjected to a high current short-circuit due to their contact with conductive liquids like water can be repaired. Water damage also causes salt crystallization and corrosion due to the continued exposure to water vapor. This crystallization of salts results in short circuits when the PCB is reactivated. The first thing that you should do is remove voltage sources such as batteries and mechanical/electro-mechanical components like relays, switches and potentiometers from the water-damaged circuit board. However, short circuits that cause components to blow up result in extensive damage. These parts need to be removed and reinstalled.

To remove congealed salts and other contaminants you need to immerse the PCB in an ultrasonic cleaner using an appropriate cleaning solution for several hours. Using industry-standard chemical solutions and cleaning agents in an immersion bath is the best way to remove all the contaminants. The cleaning process for water damaged circuits needs high frequency cleaning using high-powered ultrasound to eliminate all traces of water and crystallized residue from the board. Computer circuit boards and electronic devices contain metal and fiberglass. Water and other liquids result in corrosion when the power supply is not cut off. After rinsing and inspecting the board, it can be cleaned manually using a brush to ensure that everything looks good.

There are a few important things to keep in mind if you ever happen to spill water, tea or coffee on your cell phone or laptop keypad. Disconnecting the device is the first thing to do as devices may either explode or you might get an electric shock if you leave it connected to the power supply. You must remove the battery to stop the corrosion process.

Disassembling the device on your own to some extent is fine as long as you do not use excess force and cause further damage to the components. Depending on the extent of damage some components on the board may need to get replaced too. Using a small brush like a toothbrush is a good way to eliminate the maximum amount of liquid carefully. You cannot rely on the natural process of evaporation to dry your phone and laptop. Using a can of compressed air or a desiccant is a good option. Silica gel is an excellent agent that removes all the moisture in no time.

High pressure showers and massagers get rid of the liquid on the PCB. The board should be cleaned immediately. Leaving the liquid to dry before rinsing it with a suitable solution is not a good idea. The best thing would be to use kitchen paper to dry the wet spots with minimal pressure. A warm radiator can also be used for 12 hours to dry the PCB. Though many people resort to the use of a hand dryer to speed up the drying process, this causes irreparable damage to the PCB as the pressure of the dryer forces moisture deep into the board and into the smaller components. Solvents like chemical gasoline, pure alcohol, 90% isopropyl alcohol, distilled and deionized water are useful.

Once the PCB is thoroughly dried you can now attempt to get the device working again. Replace any of the damaged components, connect everything back together, and power up the device. In all probability your timely action will have saved your device from becoming another useless electronic brick.

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