Originally Posted by m3e46fanatic
Also, I should mention that the dial on the centre vent which controls the heat/cool is broken.
THere's your problem. For some reason this is like a master switch for the face vents and yours is stuck on hot.
Do you have the same constant heat problem for let's say, the window vents? I'll bet you don't.
If it's the thermostat your car will either overheat (stuck closed) or not warm up enough (especially when idling when driving through very cold air) and you won't have heat...