Just got the xl7 and am trying out the fetures, the rear ac comes on and blowes air, but it is only cold, i have pushed the rear control on the console but can not get hot air out of it, is this normal

Mine does not worl at all when i turn the nkob

I'm not sure how the XL-7 system works but my Suburban works with both AC and Heat. It just takes a while for the vents to clear out the hot air in summer and the cold air in winter.

Mine is just an extra blower motor and rear controls to pump the AC or Heat form the front system.

Zig

I also have a 2002 with the 3rd row seat and its the only way to get rear a/c. Heat comes from under the front seats where the middle rear seat passengers put their feet. The most rear seating area is SOL for heat. The rear ac will only work when the front ac button is pushed, the fan switch is on and the switch on the console for the rear air fan is on. The switch on the roof console is only there to control the fan speed/on/off. If you take a look, the rear ac is plumbed off the main cabin lines at the firewall. The lines follow the inside portion of the frame till they cross over at the rear axle to the driver's side behind the rear tire. In there is the evaporator. The fan draws interior air through the plastic vanes in the side panel. From there, the fan pushes the air out through the roof vents.

For the front passengers, you can have the ac on and have the climate control on hot to get warm air through the dash/foot vents. The air will be dry and not have a lot of moisture. Also, if you have the front defroster on, the ac is automatic on even if the ac button is not on.

I'm new here but my 2003 xl7 manual clearly states the rear control is for a/c only. Hope this helps.