1995 Olds Eighty Eight Royale

I'm new to this site so I will do my best to give the most info possible

I have a 1995 Olds Eighty Eight Royale with a Brand new engine with less than 28 000km on it. My car was purchased from my grandparents and I know that the car is mechanically sound in every possible way. However I do have one problem, I have lukewarm heat on the driver side of the car and ice cold air on the passenger side of my car. This started when I replace my battery...once I put the brand new battery in, the temperature control cluster would flash for 1 min then stop and would seem normal. Only when this occured the temperature of the air coming out of the vents would be freezing. I havent done anything different to my car. Once again the car was working perfectly fine and I replaced the battery which took maybe 10 min, and after those ten min without power this whole lack of heating happened.
Any help on the issue would be great since I'm in northern ontario and its -18C outside

Welcome to AF, do you have the automatic or manual hvac.

Thanks for the quick reply maxwedge

My car has an automatic hvac

Thanks for the quick reply maxwedge

My car has an automatic hvac

There is a programmer under the dash that sets the temp door based on your setting on the panel and inside/outside air temps, Make sure both heater hoses are hot to confirm good coolant circulation, then there could be a problem with a sensor, control head, programmer or temp door connections.