Is a fan better off pulling or pushing air through a heat exchanger?

Thanks.

 

Probably depends on the fan design itself, some fans are made to pull air through and some to push air.

 

From the research I've done, A pusher fan is only 80% as efficient as a puller fan.

 

puller is better

 

Thanks for the replies. How do I go about identifying what type of fan I have, or is it just about the direction (I assume all fans are reversible direction-wise though)?

 

Usually they will have a direction of flow or rotation arrow on the fan or shroud some place. Then will also have some sort of mounting flange/tabs on one side. Those two things will pretty much tell you how it is set up. If it is pulling air in from the side with the mounting tabs, then it is a puller.

 

Thanks!