Hood Fans - Blow In or Out?

[nacra99]

I'm trying to install a fan into my DIY hood.
Should it be blowing into the hood or out of it?

I've seen both and can't decide which is better.

Thanks!

[greg_tsam]

In -> blows dust into the canopy. Would be good if exterior is cooler than interior.
Out -> Pushes warm air out

You say potato, I say potatoe.

Can you create one of each and put a filter on the intake? When I built my computer this is what i did and there are premade filters that snap around the fan casing or you can easily make one your self.

[eklikewhoa]

One of each.... but most fixtures have them blowing in.

[nacra99]

One of each it is!

But another question. Can i hook up two AC fans in parallel?

[CichlidFan]

Not positive, but I believe you can...

CF

[PhishPhreek]

Depends
Its all about air flow.
I assume you are trying to equalize the temperature between the inside and outside. Therfore if the inside is warmer than the outside and the fan is closer to the heat source than the air inlet, you want to blow the hot air out. If the fan is farther from the heat source than the exit path, you want to blow the cool air in. The opposite is true if you are trying to warm up the tank.

[greg_tsam]

You could also have two fans blowing out with vent cut in the sides. There's a negative/postive pressure situation to be aware of . But I digress. Sorta.

[blacksmith37]

From an engineering perspective ; pump the cool air (in). It is more dense and the fan will move more pounds of air/watt.

[BEdward]

One of each it is!

But another question. Can i hook up two AC fans in parallel?

Yes.