LCD water damage

[SQ]

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I have a 24" LCD, Dell UltraSharp 2408WFP.

I have a child in the family that got mad and poured about half a
gallon of water on top of it.

At first, it turned on and displayed mostly everything OK except that
there was this shady area at the bottom.

Now half an hour later it turns on and immediately turns off. It also
makes this hissing sound.

Is this monitor permanently gone or will the water dry up and it will
start working again?

I put it in front of a window fan for now.

 

[Paul]

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I have a 24" LCD, Dell UltraSharp 2408WFP.

I have a child in the family that got mad and poured about half a
gallon of water on top of it.

At first, it turned on and displayed mostly everything OK except that
there was this shady area at the bottom.

Now half an hour later it turns on and immediately turns off. It also
makes this hissing sound.

Is this monitor permanently gone or will the water dry up and it will
start working again?

I put it in front of a window fan for now.

The backlights on the monitor, operate at a high voltage.
There are one or more "inverter" circuit boards, that
convert a lower voltage (perhaps 12VDC from the adapter)
to voltages around 800 to 1000VAC at a total power
level of 3 watts per backlight fluorescent bulb. The
hissing you're hearing, could be related to those high
voltage circuits.

http://en.wikipedia.org/wiki/CCFL_inverter

Other portions of the design, use lower voltages and
CMOS logic. There might be the odd bit that is sensitive
to water (maybe a crystal oscillator circuit or something).

In any case, if it was my monitor, I'd probably take the
back off it, so that it could dry better. The vents don't
allow a lot of air flow, and if left assembled, I'd want
to wait many, many days, before turning it on again.

There are a couple possible packaging concepts. My
monitor has four screws on the back, so it looks relatively
easy to disassemble. I've also worked on a device, that
used "snap-in tabs" around the edges of the casing, and
it takes great care to split the casing, without leaving
tool marks on it. (You don't want to leave tool marks
on it, if attempting a warranty repair later.)

If the high voltage gets bridged to any of the low
voltage logic, damage could result. Whether enough water
would pool anywhere inside, for that to happen, is unclear.
With the vertical orientation, the water should mostly
just run out.

The "fade to black" you're experiencing now, could be
an inverter shutting off on overcurrent, but you'd think
that would only affect a percentage of the backlights.
Being a 24" monitor, it needs multiple backlights for
uniform lighting.

You really shouldn't be turning it on and testing it,
while it is still wet.

Paul

 

[marslee]

"The shady area at the bottom": The water may get into the panel from
the edge. Sometimes after the water dry out you will see the water
mark on the panel, sometimes it won't.

Also the water may get into the reflective film( the film behind the
panel that reflects light).

The hissing sound is from the inverter transformer, when at least one
pair of backlight circuit is not working properly.

Like Paul said, you should not turn it on when it is wet.

It is hard to say whether it will work again.

if it is still under warranty, you call Dell and tell them the monitor
is not working(don't tell them about the water) and see if they can
send you a new monitor.

 

[DevilsPGD]

In message <[email protected]> "\(!\)"

Household insurance springs to mind................

Odds are good that the deductible would be more then half the cost of
the monitor, no?

 

[david]

X-No-Archive: Yes

I have a 24" LCD, Dell UltraSharp 2408WFP.

I have a child in the family that got mad and poured about half a gallon
of water on top of it.

At first, it turned on and displayed mostly everything OK except that
there was this shady area at the bottom.

Now half an hour later it turns on and immediately turns off. It also
makes this hissing sound.

Is this monitor permanently gone or will the water dry up and it will
start working again?

I put it in front of a window fan for now.

As long as it was just water (i.e. not anything with sugar in it) once it
dries, it should be fine. Most circuit board assemblies are actually
washed in soap and water following the assembly and solder reflow
process. (Have you heard of the trick of cleaning your keyboard in the
dishwasher?) The caveats are things like the LCD panel itself, and the
backlight components, which can operate at high voltage. You probably
should not have tried to turn it on until it was thoroughly dried out.

I would recommend baking it in a *very* low heat (i.e. less than 120F)
which will accelerate the drying process. If nothing has been damaged,
it may eventually recover.

 

[david]

Not if he turned it on when it was wet.





The caveats are things like the LCD panel itself, and the

Bake a monitor? You will melt the screen!!!!

Not at a low temperature. Read again.

 

[John Doe]

why bother paying for insurance if you look at it like
that..............you just might as well put that money into a
holding account and use it when something like this happens.

As far as I know, insurance doesn't make sense unless it's required
by law. Insurance companies won't insure you if they think they're
not going to make money off of it (that means they think you're
going to pay more than you ever receive). Unless it's required, it's
like playing the lottery, it's for people who are bad at math.

I go for lots of smoke detectors
Amazing how accurate they are (but for fire, of course).

Have fun.

 

[DevilsPGD]

In message <[email protected]> "\(!\)"

a load of bollox..........

If you say so. My insurance has an item called "claims free" under the
"Discounts on your property", I assume that would go away were I no
longer claim free, no?

 

[DevilsPGD]

In message <[email protected]> "\(!\)"

got the wrong insurance then numpty..........

How so? I shopped around, they fit my needs nicely, and are the
cheapest for the coverage I want.

I also have a fairly high deductible, which drops the cost of the
insurance significantly as it indicates to the insurance company that I
won't be charging every dropped plate of food to the insurance company,
but instead only rely on them for catastrophic losses.

 

[Ed Cregger]

It would be a whole lot cheaper to just trash all your computer stuff
every year and buy all new than to have kids anyway..

Not to mention much less expensive...<G>

Ed Cregger