centre vents

Hi all, sorry if this sounds silly but i'm new to the vans and wondering if the centre blower vents should only blow cold air or is there a fault with my van. It's a 2003 Longnose 888 special x pack if it makes any difference. Thanks Luke

I have a problem! My central heater blowers are blowing stone cold and the side vents scorching hot! Go figure? Can anyone suggest a possible reason and a solution before I start dismantling the dash board etc. Thanks in advance from a frozen T4 driver...Adrian