Opening a SFX PSU to clean it. Risks?

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I've an over 5 year old Silverstone 450W SFX psu, which I removed from my old machine recently. Works fine, a great little psu. I'd like to put it back in a new build, but it looks like it's got a fair amount of dust build up. I'm considering opening up the case to give it a good clean.

Has anyone done this? What are the pros and cons? Is it easy to screw something or are they fairly forgiving things to open and clean. I'd only give it a good going over with some compressed air, I wouldn't bother replacing the fan or anything like that.

Any advice greatly appreciated.
 
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Use the air blower from outside. A decent one should be able to dislodge all the dust unless you ran it in a kitchen with greasy air or are a heavy smoker.
 
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Thanks for the replies guys. @SupraWez I'm not sure that will do a good enough job tbh. I would presume I'd likely just end up blowing dust more deeply into the case? Plus there's the possibility of causing an issue with dust shorting something because of it.
 
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Dead easy to open and clean. Obviously only do it with it totally unplugged.
Be aware that some caps can hold charge for some time, so leave in unplugged for a few days before opening and still tread carefully, dont touch internals... Act like it can kill you with one bad touch. After a few days unplugged the caps will be empty, but better to be safe than sorry.

Do it outside, dust goes everywhere!

Soft clean paintbrush to loosen it up, canned air to blast it.

Screw it back together.

Dead easy, will take about 10 minutes if you are taking your time.
 
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Thanks for the replies guys. @SupraWez I'm not sure that will do a good enough job tbh. I would presume I'd likely just end up blowing dust more deeply into the case? Plus there's the possibility of causing an issue with dust shorting something because of it.
I guess it's either of these particular models so indeed would be hard to clean without opening:
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story3&reid=196
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story5&reid=319

All good PSUs have bleeder resistors for primary caps, so after couple hours disconnected from wall there shouldn't be much charge left.
But as that PSU has good old colour coded wires you can attach 24 pin cable and short green wire to black with paperclip etc.
That "orders" PSU to start further speeding draining of primary capacitor.
All other capacitors simply can't store much any energy/have low voltage needing touching them with tongue for anything to happen.
 
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Thanks again everyone for the replies.

@EsaT Thanks for that, that's incredibly useful. Mine is the one in the first link. However, it does looks mighty fiddly to open up doesn't it. I'm erring on the side of just blasting it from the outside instead now! Decisions decisions. Anyone wanna tell me it doesn't look too bad to open and it'll go back together fine? :);)
 
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Would be really hard to get dust out of there without such air pressure which isn't exactly gentle for small components.
Also high pressure air can easily overspeed fan damaging its bearing.
And certainly would want to make sure dust isn't blocking airflow to those cheaper capacitors.

Looks like it has screws on top and bottom and one screw in cabling end attaching cover to heatsink for using it in cooling.
With fan's cable limiting how far "cover" can be pulled.
https://www.pcper.com/reviews/Cases...SF-450-watt-Power-Supply-Review/Detailed-Look
Heck, it's age would warrant taking look at those capacitors.
 
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All good PSUs have bleeder resistors for primary caps, so after couple hours disconnected from wall there shouldn't be much charge left.But as that PSU has good old colour coded wires you can attach 24 pin cable and short green wire to black with paperclip etc. That "orders" PSU to start further speeding draining of primary capacitor. All other capacitors simply can't store much any energy/have low voltage needing touching them with tongue for anything to happen.

Thanks again @EsaT I've just done the paperclip on the 4th(green) and 5th(black) wires to power it on to check it's still working and it powers on fine. Are you saying that leaving the paperclip there for a while (power plug in or out?) is effectively speeding up the discharging of the capacitor? If so how ong do you reckon I should leave it for? I've a mind to do this asap now so would rather not wait a few days.
 
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Are you saying that leaving the paperclip there for a while (power plug in or out?) is effectively speeding up the discharging of the capacitor?
With cord disconnected from wall that will certainly empty primary capacitor for as long as PSU's electronics can operate on remaining charge.
With that bleeder resistor doing rest there really shouldn't be much any kind charge left after hour or two of waiting.
 
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Job done.:) Opened far easier than I thought it would for its size. There was a heck of a lot of dust inside, I really don't think external cleaning would have shifted even half of it. The capacitors look good, though I'm no expert. I was just checking for any signs of bulging. Turned it on and it all starts up ok.

I was a bit concerned when @EsaT mentioned the fan bearings could be damaged, as I'd previously use the vaccum externally earlier, which sped the fan up a fair amount. However, it sounds pretty good, ie couldn't hear it much above a light whirring.

I intend on doing a voltage check when I come to putting the new build together, just to be on the safe side. But I think it was totally worth it opening it up. I feel much better about putting it in a case with new componants.now.

Huge thanks again everyone for your input!:)
 
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Job done.:) Opened far easier than I thought it would for its size. There was a heck of a lot of dust inside, I really don't think external cleaning would have shifted even half of it.
Enough dust would be even minor fire risk, if something heats up too much or some semiconductor desides to blow up causing spark.
Though would have to be lots of dust for it to be able to do more than give little smoke.
(enough heat and plastics of fan could melt and start burning)
 
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