We Have two central a/c units in our 5 bedroom house. The upstairs one is in the Laundry room and has no vent on the door. we Noticed it pulls the door shut when it goes on. I figure this means the a/c unit needs to intake air, so I prop the door open and have been asking my mother to get a door with a vent so that I can Install it. She has vehemently refused and closes the door whenever she finds it open. she swears it Costs more money leaving it open, and makes the a/c work harder. who's right? by the way, the downstairs one has a vent in the door but you can still feel the pull if you open it while it is running.

I forgot to mention the a/c unit is in it's own room in the Laundry room. It's that Door that I am referring too. NOt the Laundry Room Door, although this pulls hard as well when the A/c is running and I have propped the A/c door open.