AC Blows Warm

[BlueTahoe98]

My 98 Tahoe is blowimg warm air. The low and high side pressure seems OK.
Added UV dye to the system and see no leaks.The aluminum chambers do get very cold and to the point where frost develops on them. When moving the temp dial to hot the fan will blow hot air. Any ideas?

 

[lesterl]

Bad temp actuator servo, bad control head, bad coolant shutoff valve (is there one on yours?)

 

[Jounier11]

Most likely your compressor and canister need to be replaced if i were u i would get them rebuilt!!!!