HACKER Q&A
📣 RGamma

How to deal with a possibly liquid-damaged monitor?


Greetings,

yesterday a small liquour-filled rack detached from the wall and a bottle of sugary liquour crashed on my SO's monitor (recent AOC 28" 4k panel).

The frame split cleanly open and a few ml of liquid spilt through the ventilation grate on the controller board and internal PSU.

Instantly pulled the plug (it was on standby), and turned it on its head which seemed to have prevented worse. On first inspection the panel doesn't seem to have cracked or sustained liquid damage, but I'm worried about the PSU. Searching online I could find quite a lot about cleaning "regular" PCBs, but nothing about PSU components (seems to be forbidden territory).

Pictures, bad quality I know:

PSU front: https://ibb.co/JnLpf67 (a few splodges)

PSU back: https://ibb.co/0rH65HG (most visible gunk)

Controller front: https://ibb.co/BgxhSpT (some gunk here too)

The controller back looks pristine.

The panel power supply port (top of first picture) has stuff in it as well. My plan is to carefully clean with 99% isopropyl alcohol on a Q-tip and a tooth pick for the hard to reach places, e.g. inside the connector, followed by hair dryer treatment. I read some soak it, but that might not be a good idea with the coils, foil and all and is probably overkill.

Then I would stress-test it for a few hours in the yard and see if it goes up in flames.

Do you think this is a sane way to handle this? Any (longer-term) failure modes I should be aware of?

I would be sad to throw it away since it's quite new and expensive. Thanks in advance.


  👤 jaclaz Accepted Answer ✓
Usually the "forbidden territory" about PSU's is only about the fact that they are (were) connected to mains, if you give the PSU the time to let the capacitors discharge (a few minutes in the worst cases) they are perfectly safe.

What I would do would be to wash it with distilled (or demineralized) water first.

If the gunk goes away, there is no need to use the isopropyl alcohol at all, but otherwise a quick immersion in isopropyl is also ok.

Both with distilled water and isopropyl alcohol, I would find a suitably sized container and put in it just the right amount of liquid to cover the part(s) where the gunk is visible (the top right connector in your case).

Distilled water won't do any damage and you can leave the PCB in it as long as you want (to give it the time to moisten/dissolve the sugary gunk), with isopropyl alcohol there won't be any damage to the actual components, but if you keep it for long you may well have some esthetic damage (like discoloration of some plastic).

There should be isopropyl alcohol available in spray cans too, I wouldn't go for contact cleaners if not for the actual connector pins, after they are cleaned, at least the types I am familiar with do leave a (protective) residue that is good on the actual connectors, but that you don't want elsewhere on the board.


👤 anenefan
I've used isopropyl but as a fast flush to remove a quantity of moisture / water, followed with a prompt drying with a blast of air. Isopropyl will actually absorb moisture from the air so sometimes it's not an ideal choice for boards that are already dry and there's no access to compressed air via an earthed (ie human skin contact who themselves are grounded) steel nozzle.

Note, isopropyl does not agree with some plastic surfaces or finishes.

Probably I'd suggest using a quality electrical contact cleaner, which usually is available as a pressurised spray pack. Generally they're designed to dry residue free, some offer contract cleaners offer a protective coating as well.


👤 pr07ecH70r
Isopropanol should befine.

Some years ago I did something similar on my DELL monitor, but with coca cola. Cleaned everything with isopropanol, let it dry for a day just to be on the safe side, and tested. It still runs even today. PSUs are robust.


👤 imaginarycoder
Usually that’s not random, how in the world did you manage to do that? All the best.