I've got a lazyne micro floor pump (this one: http://www.lezyne.com/products/hand-...loor-drive-hpg)

There is a problem and I can't figure out what to do. The pump will compress down but obviously the air is being compressed inside the pump itself, not exiting into the hose (I took the hose off and nothing came out).
I feel like I'm missing something obvious. Has anyone else experienced this? I can't tell if it's busted or I am just overlookign something simple.

I appreciate any help.

Thanks.