Visiting Georgia in July. The A/C goes out, only blows out hot air(real hot in Georgia in July). I go to the Chevy dealer and they say that the HVAC control head is bad. They want $240.00 to replace it. I decline , and the tech says that he can manually change something to allow the a/c to work but I won't have any heat. No worries ,it is summer, so I get him to do it. Now I am back home in Minnesota and it is starting to get cold, so i go buy another HVAC control head ,but it still won't blow any heat.I was wondering if anyone knows what the tech did to change from heat to A/C?I would like to change it back for the winter or if anyone has any suggestions as to what to look for to fix the problem for good. Thanks,

 

probably manually moved the selector flap in the air box possibly the motor is bad not sure where it is i think behind glove box somewhere