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Recovering Moldy Electronics?
cookiej writes "We just completed having our basement gutted and our house decontaminated from mold. The finished basement is gone, my office floor has been removed as well as 24' of drywall around the base of the room. So, we had a full home theater downstairs along with a couple of computers in the electronics closet that were completely immersed (rainwater, not sewage). We moved them to a sheltered area outside and covered them with a plastic tarp. Since the electronics were off when the water hit them, 1) do I have a chance of recovering them? 2) If so, is there a way to clean them with some sort of liquid bath that would not damage the electronics? and 3) I don't want to bring moldy pieces back in the clean house. How could I decontaminate the electronics themselves, pre-bath? Not looking to save the speakers, just the amp, DirecTV box, video switch, etc. Thanks for any help, here, Slashdot." Read on for more details of this reader's plight.
Early last month, we had about 10" of rain in the course of two hours. Many houses in our neighborhood were damaged. We had rainwater coming in our back door and cascading down the basement steps. We have two sump pumps that weren't keeping up (and of course, no battery backup) and as the water rose in the basement, it was getting dangerously close to the breaker panel. So I made the hard decision to shut down the main power and we got the hell out.
The water reached about 6' in the basement before it drained out. Once we got back, we could not move fast enough to get all the debris out before mold set in and boy did it.
Since we are not in a flood plain, our insurance for this is woefully inadequate. While I would love to just go out and buy replacements, there are far more pressing things to re-buy (washer/dryer, furnace, water heater, etc.) and if there is a chance I can salvage some of this it might be a nice change of luck.
Early last month, we had about 10" of rain in the course of two hours. Many houses in our neighborhood were damaged. We had rainwater coming in our back door and cascading down the basement steps. We have two sump pumps that weren't keeping up (and of course, no battery backup) and as the water rose in the basement, it was getting dangerously close to the breaker panel. So I made the hard decision to shut down the main power and we got the hell out.
The water reached about 6' in the basement before it drained out. Once we got back, we could not move fast enough to get all the debris out before mold set in and boy did it.
Since we are not in a flood plain, our insurance for this is woefully inadequate. While I would love to just go out and buy replacements, there are far more pressing things to re-buy (washer/dryer, furnace, water heater, etc.) and if there is a chance I can salvage some of this it might be a nice change of luck.
I moved from Ca to Co once. In winter.
In a storm.
In the back of a truck.
Get the idea?
LOADS of electronics got wet. Some took, literally, years to get working again.
The BIGGEST thing you can do to save your stuff is this: GET IT DRIED THE FUCK OUT. Water is corrosive to the copper in the products you have (besides the electromechanical problems, like bearings in hard drives (old ones), etc), and if left to do it's thing, electrolysis will eat them up.
I ended up having the entire back of my truck filled with the style cartons you find at 7-11 or something similiar. Split top, about 12 to 18 inches deep. My tarp had a rip in it, unbeknownst to me, and when I stopped, THEY FILLED WITH WATER.
The next day, I made my destination, and the day after that, I got the screwdriver out. EVERYTHING was cleaned off with a rag internally, and I ended up losing about 10 percent of the devices.
Don't power them up until you KNOW everything is dry.
Any transformers, if your really worried about (read, if they are HEAVY and expensive), can be desoldered and heated in your home oven, on it's lowest setting (they can take > 150 degrees easily). That will bake out any moisture.
Ditto for some really high power transistors. One trick we used in making REALLY high power CB radio amplifiers was to bake the transistors for about 2 hours. This removed ANY moisture under the caps of the 2879s (part number 2SC2879). This netted us about 2 to 3 more volts on the collectors. After talking to engineers, we found that even a LITTLE bit of moisture in there, will turn to steam after the devices reach their internal operating temp. Higher voltage on the collector = higher temperatures (more dissipation). Baking them got us 2 to 3 more volts and that equalled a few hundred more watts (for every 50 percent increase in supply voltage, your Pout doubles) (think, 24 to 64 transistors being combined).
Simple green or even lysol does well for mold inhibition. You can also do a 5 % bleach solution, but then you run the risk of losing color, faceplates, some plastics, etc.
Hope it helps.
--Toll_Free
Heh. The good news was that our HT setup is a Front-projection and the projector was on the ceiling. The lens cap that hangs down had a thin line across the top third, indicating how close the water came to ruining it. And that one I don't think would have survived. Those bulbs are quite sensitive.
The screen was home-built for around $80 in parts, so I can re-create that. But the whole "down to the studs" thing is
>
Finally, where do you live? 10" of rain turns into 6' of water in a basement when you don't live in a flood plain? Why would anyone build a basement in an area subject to such problems? (I live in an area without basements, both because of shrink-swell soil and high water tables.)
Well, it was the worst rain in 135 years. So the phrase "subject to" is... well, quite subjective.
Quite a few posters have said this is a write-off without even seeing the state of the kit in question. That's pretty pessimistic! Here's a tale that should give hope:
Many years ago I worked in the service department of an electronics OEM repairing stuff returned from the field. The OEM built two-way radios. One time we were sent a portable radio that had been recovered from the sea-bed having been dropped from an oil-rig in the North Sea six months previously. The unit had a die-cast zinc/aluminium chassis and case and standard double-sided PCBs with mostly discrete components and a few ICs. It was extremely corroded, covered in salty deposits, and naturally didn't work. I was written off immediately but as a 17yo with time on his hands I took it as a challenge. I cleaned up the unit by passing it through the tanks of hot trichloroethylene that were used for cleaning newly assembled boards. This removed most of the surface corrosion on the PCBs and chassis. An open-framed rotary switch for channel selection was replaced as it was too far gone.I ran the boards through the normal service/setup procedure. The receiver came up no problem with basic retuning. The transmitter was dead but only needed a new final stage transistor and a retune. It passed spec. It was returned to the customer along with a new replacement unit. They were astonished and very pleased with the customer service received beyond the call of duty or expectation. Whether it was connected I don't know but they placed a huge order with us several months afterwards...
The kit here was immersed in fresh water for much less time. While component densities are much higher in modern kit, I think there's a good chance it will work after careful cleaning and drying. Worth a shot anyway - what have you got to lose?
Interestingly enough, one of the computers that got dunked was an old Apple Cube I used to monitor my UPS and other various cron jobs. It as no fans, so we'll see. The bad news is that it may have been powered when the water hit it. It was at the bottom of the rack and the water was at about 3' when I killed the power.
The real test will be the PS3. It was at the top of the rack and probably was barely under. Amazingly, my network gear and the UPS that powers it were all at a height of about 6'4". And never were touched.
Well, we are at a somewhat low point in the area, but also right next to a storm sewer. We haven't had water before this so I was quite surprised to see the water forcing itself through the bottom and sides of our back door.
Our storm sewer has been known to get clogged and start to back up toward our house. But I usually just go out, clear the sewer with a rake and that's the end of it.
Actually, I *DID* exactly that earlier in the morning of that day. Wife threw up the alarm that the water was starting to pool, so I went out, cleared the sewer... watched it all drain in, no pool... and went back in and started breakfast. Before breakfast was over, I heard something strange and thought one of our gutters was overflowing. Only to find the newest waterfall down to the basement.
No! Bleach BAD. Bleach will oxidize all the metals, including the ones you thought couldn't rust!
I have washed boards in the dishwasher before (no soap!) but that was for spilled liquids. With the presence of mold, you have a different problem.
First, remove any batteries on the board (coin batteries are common,) as they create a sparking hazard. Use pure isopropyl alcohol (not the 66% stuff) which will mix with remaining water and should help you both clean up and kill the mold. I'd start working over an empty pan, and pour alcohol over it as I cleaned it. Brush everything possible with a natural fiber brush (not a plastic bristled brush that may dissolve.) Get under components with a pipe cleaner. And no smoking around the alcohol, of course! When it's done, drain it. If you have access to it, thoroughly blow it dry with dried compressed air (air from an ordinary shop compressor will contain water and/or oil.)
Once the visible alcohol is gone, you'll still need to dry the board. It will take time, warmth, and air movement. An oven at the "keep warm" setting (no more than 170 degrees) shouldn't damage the plastics, but not while it's still evaporating alcohol fumes. A fan and some incandescent light bulbs (desk lamps up close) would probably do just as good. Warm sunshine is very good, too (and helps kill mold) but the humidity outside is usually pretty variable, so you wouldn't want it to remain outside in the evening to collect dew.
However, be prepared for disappointment. If there are electrolytic capacitors on your board, there's a good chance they were already destroyed by the water. They are not typically sealed to ward off immersion in liquids.
John