EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: todorp on February 27, 2022, 05:39:13 pm
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Hi all, do you think it is possible to "revive" a battery powered device which has been in salty water?
The device has been dropped in the water and then immediately fished out and the battery disconnected immediately. The device however has not been cleaned and has been left as is for a few hours.
The question is: what would be a way to wash the pcb from salt residue?
Thanks,
Todor
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Salt can be cleaned with water, preferably in ultrasonic bath and with special cleaning chemicals added. However as it was a salty water likely there is a corrosion too, and simple cleaning will not be enough.
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What kind of device?
I once tried to "repair" a graphics card which had artifacts
by putting it in a dish washer (after removing heatsink+fan).
The repair didn't work, but neither did it get worse.
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I once tried to "repair" a graphics card which had artifacts
by putting it in a dish washer (after removing heatsink+fan).
The repair didn't work, but neither did it get worse.
If it has artifacts, most likely you need to replace a faulty RAM chip. Not wash it. The only case when it may need washing is when liquid cooling leaked onto it.
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What kind of device?
I once tried to "repair" a graphics card which had artifacts
by putting it in a dish washer (after removing heatsink+fan).
The repair didn't work, but neither did it get worse.
It is a friend's FireFly 2 vap device..
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Salt can be cleaned with water, preferably in ultrasonic bath and with special cleaning chemicals added. However as it was a salty water likely there is a corrosion too, and simple cleaning will not be enough.
There is corrosion too - is the case hopeless?
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If it did not destroy any traces or components then cleaning will be enough. However usually you will need to repair what was damaged. Certainly not hopeless, but can be quite tricky, especially if there are small BGA chips.
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Soak overnight in DI (distilled) water, refresh water and soak again overnight
Dry in oven 150-180 degrees F for 12 hours.
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pH balance of the salt residue is bit high (more to be alkaline) and that’s why
normal cleaners may only smear.
So suitable cleaner must be low/mild acid pH level, which should neutralize it
e.g.
vinegar, one of your food in kitchen
acetic acid, same, just one not natural, it's synthetic of it
both should be about 33-70% conc.
citric acid is alike, some citrus fruit juices
as usual and must: has IPA as a finishing touch
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Solder resist is quite hydrophobic. That is, it does not wet. If you can find a non-ionic detergent, I would add some to the first water wash at least. Absent that, then use any convenient liquid detergent.