It doesn't really make a load of difference which way it's pulling, especially with a small volume area like the empeg's case, as it's not going to create any significant vacuum or pressure, so either way you're still pulling in external air. And unless the fan itself is generating significant heat, which I seriously doubt, it's still going to do something positive if the external temperature is lower. (Obviously, if it's 1F lower it's not going to do much regardless, but you get my point.) In other words, if the fan makes it worse, a better fan is going to make it just as worse, if not more worse.