Mine made horrible noises. It was the little fan inside vibrating against the compartment it sits in. I took it out and attached a fan I stole off a busted converter, and mounted it externally.
First attempt failed as it didn't cool enough. I tried it the other way around and it works great, no noise. I don't remember whether it sucks or blows as being the right way around. Perhaps you can tell from the picture of the blades.
EDIT--it blows outwards (sucks from inside) You have to also wire it so it will turn that way I guess. Can't recall if that was needed. Been several years.
I ran the new fan's wires inside and spliced them to the old fan's wires.
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