I went ahead and had the local electronic repair shop throw in a new fan in my A2000 psu, as the old one was getting pretty loud and I'm not so good with a soldering gun. And instead of blowing air out, it now sucks air in, so I called and said I thought it was backwards and he said he did that on purpose because it's better to pull air in for cooling than blowing air out, and that it will increase the lifespan of the psu and the fan because you're not dragging hot air across it, and that all the modern psu's do that...
Bad thing about blowing air in is that it blows more dust in.
Good thing about blowing air in is that your computer should run a bit cooler.
I'm OCD about such things though and if the A2000 should blow air out then that's how I'd want it to remain.
If you like you can turn the fan around yourself maybe (depending how long the fan wires are). TBH, if the fan is soldered to the PCB I'd have put a fan plug socket on it so the fan can be easily replaced in the future.
