My 1995 Riviera temperature control has Hot-Hot air coming from passenger side air ducts, outside air temperature from drivers side ducts. The AC compressor is not operating. All started with a totally discharged batery from a trunk being left open. The air ducts change OK from top to bottom when different modes are selected.
I believe the "doors" that control discharge air temperature (into the passenger compartment) are electricity activated. Check your fuses. Perhaps one or more blew when you replaced the battery. HTH. -JIM
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