One or more heater & AC (HVAC) air delivery and/or temperature mode door actuator may fail. This can result in incorrect air delivery or temperature. If this occurs, fault code(s) stored in the HVAC control module should be available to assist with diagnoses.Google+
Car Problem Reports
Chevrolet Avalanche 2500 Heating and AC Temperature and Air Delivery Mode Door Actuators May Fail
Chevrolet Avalanche 2500 Problem
Visitor, 2002 Chevrolet Avalanche 2500, 58,000 mi
Okay my first response was lost in cyber space - that sux...
My truck is actually a 2500 but I have been told that the cabin and controls are the same as the 1500 so I posted this on that category as well.
Time of year - winter. Heater controls on full heat.
Cold air coming in on the far right side of the heater box when the fresh air / recirculate control is in the fresh position.
Switching to recirculate stops the flow of cold air, but only until the system switches itself back to fresh air mode (like five minutes).
I bought the truck new and it is fully loaded with all the options. No prior service required on the HVAC system. Looks like I get to do some trouble-shooting.