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AIO cooling. Why is it done backwards?

Bobert

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My AIO cools by sucking air down through the unit. This is against the natural convection. My unit actually heats up a bit if the fans turn on low because the venting actually slows a bit. Why don’t the fans blow up into the unit instead of sucking down?
 
I looked at the manual. It looks very similar to my growatt that the fans blow through and out the sides. I wander it they simply installed them backwards.
You may reword your post to powmr backwards fans though.
 
All the ones I've seen. None have fans at the top, all have them at the bottom.
I guess the idea is, if you have holes at the top, moisture gets in more easily.
Also, they all seem to have noisy fans. I guess the idea is, if we can save 20 cents on fans...
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All the ones I've seen. None have fans at the top, all have them at the bottom.
I guess the idea is, if you have holes at the top, moisture gets in more easily.
Also, they all seem to have noisy fans. I guess the idea is, if we can save 20 cents on fans...
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My understanding is his fans at the bottom such down through instead of blowing up and out the top sides.
 
Yes, so do all the ones I've seen (not many).
Up and out the top sides does sound more reasonable.
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When my fans are off the natural convection moves quite a bit of air I don’t understand why they don’t go with the flow the fans would be much more effective.
 
When my fans are off the natural convection moves quite a bit of air I don’t understand why they don’t go with the flow the fans would be much more effective.
Go with the flow is the way to go. Check with PowMr. If they won’t exchange, add your own fan. Amazon has super quiet USB, 12v and 120v models.
 
My Multiplus has the fan on the bottom and it blows hot air out the top.

I installed some DC computer fans to help ventilate the compartment. If I wired them backwards they didn't do anything.
 
My AIO cools by sucking air down through the unit. This is against the natural convection. My unit actually heats up a bit if the fans turn on low because the venting actually slows a bit. Why don’t the fans blow up into the unit instead of sucking down?

Sounds like the fan was installed upside down, flip tit over.
 
They have intake filters.

Nearly all of this class of equipment blows down.
Just to clarify something my AIO is not overheating it cools fine and is quiet enough to not be annoying even when the fans are on full blast. My unit does not have filters on it. The way I have the AIO mounted creates a bit of a chimney effect. I can be creating and using nearly 300 watts of power before the fan comes on. It comes on at 45 degrees Celsius and turn off at about 40. I hate to mess with something that is working but I can’t help wondering if it would work better with air blowing up from the bottom
1. The airflow would be increased as the natural current is in that direction
2 the fans would not have to overcome the chimney effect created by my mounting location.
3. The unit would not be recirculating air that has already been heated by traveling through the unit.
4 the fans should last longer as the would have less drag and run cooler since they would be blowing cool air in instead of sucking hot air out.
The unit would potentially run quieter ( it’s not particularly loud now) as high speed fans would be less likely to be needed.
 
Some people have turned their fans around (there is an instruction thread on it on another forum) however there are some potential downsides to this. The temp sensors used to control fans may read differently because of the changed airflow dynamics and I also believe in some cases it's to reduce the chance of condensation forming inside the unit. I haven't thought too hard about whether that's a real phenomenon or not.

I figure they designed them that way for a reason. I did consider opening mine up and flipping the fans around but it operates as it should so I see little point in changing it.
 
The first pimp everyone makes to this AIO inverters is to add extra vent(s).
And even better if this vents go all the time.
There are components inside without temp sensors that go hot.
So a constant slow airflow makes wonders to your inverter's lifetime.
And the main noisy vents do not run as much.
 
Not on an inverter but I have flipped fans around on equipment due to stupid design ideas before, like some daggone PC that had the power supply fan blow INTO the PC case. It ran a lot cooler and quieter after I switched it.
 
Yeah, this is very common. Pretty much all of them are like this. They are designed to work that way, and it confused me for a long time.

I talked to a bitcoin miner who designed large scale systems, and he says that convective flow would contribute very little benefit here. The air will go where you tell it to. The amount of air that the fans push through the unit is plenty for dissipating the heat. Whether you add convective flow into the equation or not will not change performance by any noticeable amount.

You can run your own experiment. Hang the unit upside down and put a heat camera on it. If there is a huge difference, let us know.
 
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