ATX PSU fan ?

[bianchi77]

Guys,

I got one ATX PSU, suddenly its fan is off...
It's it normal if temperature is cold ...or it must be on always ?
Current temperature surrounding now is about 10 degree

[stj]

Re: ATX PSU fan ?

make & model would help.

there are only a few that completely stop the fan.

[bianchi77]

Re: ATX PSU fan ?

Macron Power
Model MPT-301
Low Noise Temperature Controller

[stj]

Re: ATX PSU fan ?

no experience of those.
others will know.
probably a dead fan though.

[bianchi77]

Re: ATX PSU fan ?

Ok, I'll check the fan and will replace it if broken...thanks

[bianchi77]

Re: ATX PSU fan ?

I've tested the fan, it's working perfectly outside the circuit....
could it be something else ?
The PCB code :
LT-20Z 0340..

[bianchi77]

Re: ATX PSU fan ?

following the example circuit....could be the failure of Q8 transistor causing the fan fail ??

[diif]

Re: ATX PSU fan ?

Macron Power
Model MPT-301
Low Noise Temperature Controller

To me the title says it all. Low noise, perhaps it achieves this by not using the fan when it's not required ?
Warm up the PSU with a hair dryer and see if the fan spins up.

[bianchi77]

Re: ATX PSU fan ?

I got no idea, but I put diode with 12V and fan..and it always on now...only abit noisy...fan at full speed...but that's allright...it's on and making the system cooler...that's it..

[momaka]

Re: ATX PSU fan ?

Macron Power
Model MPT-301
Low Noise Temperature Controller

Does it look somewhat similar to this:
https://www.badcaps.net/forum/showpo...postcount=2230

If yes, I don't think the low temperature should cause the fan to stop. This is a really old PSU - way before the days of silent computing, so the fan should run.

That said, my MPT-301 came with a completely seized fan, so maybe check yours as well, especially if the PSU is very dusty or if you have the same Superred fan as me.

I got no idea, but I put diode with 12V and fan..and it always on now...only abit noisy...fan at full speed...but that's allright...it's on and making the system cooler...that's it..

I do NOT advise you continue to run the PSU like that. IIRC, the MPT-301 and MPT-401 have their fans' negative wire connected to the -5V rail, so you may be running that fan on close to 17V! At that voltage, the fan will pickup dust pretty quickly and its bearings will fail sooner rather than later.

This PSU has a fan controller that works very well, so FIX IT! Just check the fan output transistor. Better yet, warm up the PSU with a hair dryer as diif suggested, and see if the fan spins. Maybe the cold temperature really is causing the fan controller to turn OFF the fan. I never tested mine at such low temperature, so I don't know for sure.

Other than that, this is a great solid PSU. Just make sure to recap it, especially if you have "GL" or "CS" brand caps. Fuhjyyu isn't any good either, but they are still better than the aforementioned brands. Also, beware of conductive tan/brown glue - if you see any near or on the primary side, remove as much of it as possible. The conductive glue could also be the reason why the fan is not running on your PSU. If you see any globs that have turned brown, remove them.

[bianchi77]

Re: ATX PSU fan ?

nope I put the fan on ground and +12V with diode ....so less than 12V ...
I have closed the lid already....it's the same with the photo on the link...

I'm not using a port from fan...soldered myself to ground and 12V...so far it's running perfect....soak test for 6 hours non stop already...

I know it has fan controller...may be later I'll find out what's wrong with it...

[momaka]

Re: ATX PSU fan ?

Okay, but definitely recap it if you haven't done so already!

[bianchi77]

Re: ATX PSU fan ?

Yes I have recapped it...thanks