Question Cleaning a Computer PSU

[Marky000]

Guys, I know this question has been asked hundreds of times but my question is more specific.

I have a PSU that is tripping my circuit breaker and has happened another location as well. I'm fairly sure its due to dust wedged in the PSU. I say this because it was working fine until I tried to remove a massive amount of dust by blowing air through it. Ive now used a proper air compressor to finish the job and its as clean as a whistle.

However, I have noticed a fairly tightly packed chunk of dust sitting under the PCB and I think its possible this may have been causing the short. I am thinking of using a wooden tooth pick to pry it out or at least loosen it and then blow more air through it. I don't plan on fully opening the PSU as it seems I have to pry it open with a screw driver or something. And thus blowing air under the PCB whilst in the case will most likely just wedge it even more.

So, can anyone with some electronics knowledge tell me if what I am about to do is safe enough. If you have a look at this image:

https://imgur.com/a/zCT4hxB

View: https://imgur.com/a/zCT4hxB


The dust is stuck under what appears to be a yellow capacitor (X capacitor I think) and some smaller blue capacitors. It seems that these capacitors are there to smooth out the AC variability before moving on the the next stage of converting AC to DC.

The image uploaded isn't actually my PSU. With my PSU, the blue disk capacitors sit between a yellow capacitor and an inductor. The dust is wedged mostly under the blue caps but towards the edge of the yellow capacitor.

The PSU has been unplugged for about 24 hours and plugged into a motherboard with the PSU turned on.

Am I safe to proceed with sticking a wooden tooth pick in there? I'll try not to touch legs under the PCB if possible.

 

[Lutfij]

With everything said and done, you forgot to mention the age of the unit let alone the specs of the system that it's powering.

Please include/list your specs like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
OS:

Cleaning a PSU is actually pointless especially when the unit might be built with sub par componentry(i.e you're wasting your time).

 

[Marky000]

With everything said and done, you forgot to mention the age of the unit let alone the specs of the system that it's powering.

Please include/list your specs like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
OS:

Cleaning a PSU is actually pointless especially when the unit might be built with sub par componentry(i.e you're wasting your time).

Well, I didn't mention the brand of unit etc because it isn't well known and yes quite old. It's an iCute AP-750AS 750W. did quite of looking up on it and whilst some sites called it a ticking time bomb, other sites gave it positive review. Not sure if I can link external sites but this site gave it a good review : http://forums.aria.co.uk/forum/hardware-related/power-supplies/18190-recommended-power-supply-brands

After reading all the various reviews, my take is that people just don't know that much about them as they tend to serve the Asian market more. People just hear the name and assume another cheap PSU. I suspect that isn't the case with a few people stating that these units actually use Japaneese caps. Company still trades : http://www.icute.com.tw/en/

Reason I didn't list the full system is that right now it is just a case and PSU. I run an IT business and inherit older computers as like free trade-ins etc. I service them sometimes and sell on Gumtree or eBay. I have a some potential buyers. I knew there would be some interest because modular 750W PSU new is very expensive.

As for whether cleaning it is pointless, it has already been cleaned and I have potential buyers. It is just this dust under the PCB that I want to remove before I re-test. Could have sold it already but obviously can't until I have tested it properly.

It was originally in a system running a Q6700 and a HD 4850. To me 750W seemed like overkill for that system, prolly only needed a 550W.

It is an old PSU, Around 10 or more years old. However, I don't know how much use it has had and if it has lived this long, maybe those folks who said this was actually a well made PSU were right. Apparently iCute is the parent company of Lian Li who make PC cases and it is also rumoured that iCute was actually the first company to design/make a modular PSU. iCute did make cases as well, those ones with the big 250mm fans etc.

When I removed the dust, the PSU looked almost brand new, not a spec of rust. The metal case seems to be some type of shiny alloy that seems to be rust proof.

Anyway , with all that aside, getting this back on topic. Anyone with some decent electronics knowledge can advise me as to how safe it is to remove the dust?

 

[Marky000]

Alright, I managed to get it out and blew some more compressed air through it. The compressed air had a tad of moisture so I think ill wait 24 hours and test.

 

[Marky000]

Well, the unit is still tripping my breaker. Yet no dust. And after it tripped twice, the switch wont go back to off position. I just can't figure out what happened. All I did was blow dust out of it but there was a lot so maybe that cause a lot of static?

The air compressor I used did seem to have a small amount of moisture as I could feel cold dampness on my finger. I did hold the compressor at a distance and did let it sit for 24 hours to dry out just in case.

This PC was picked up off a verge collection so I guess there may have been a problem. But I did boot it to BIOS just fine and then I stripped the parts. Only after blowing out the dust, did the unit start to trip my breaker.

Maybe because it hadn't been on for long time, first boot-up was ok? would have thought the opposite. Like, a fully discharged capacitor would pull more charge and hence more likely to trip.

When I was cleaning the PSU, i did accidentally drop a screw in the unit but i'm like 95 % i shook it out. I could see that being an issue if got stuck under the PCB but everything looks good under the PCB.

Thoughts?