No tower, that's not correct as you have discribed if I understand what you're saying. There are time you have to press the button twice. Let me think
Do you have the convenient stops?? If it's doing it there, that may be correct. I don't have the convenient stops the manual talks about but there is one situation where I have to press the button twice. I can't remember and I can't check right now because my console is torn apart on another project. I'll check tomorrow when it's back together & let you know. I do know from the normal closed position I only have to press once to either vent, or open. I think if I stop it somewhere in between open & close and want to reverse the direction I have to press twice....I think. Let you know.