Actually when you start up the car on a hot day the recirculation does come on automatically (and I think it ha come on from time to time on really hot days as well). But you are right it does shut off after a few minutes (so the sytem doesn't get iced up). Just looked in the manual, it does say (at least in the Canadian manual, that the recirulation will come on automatically when required. There is also a timer mode when you hold down the recirculation button for more than three seconds. The recirulation is supposed to automatically shut off 10-15 minutes after being pressed, if it is actually 3 minutes it may be a bit short. Hope you figure this out.