Is a mini split not suitable for very cold climates?

I have an old house with central air. The upstairs gets zero air and is stifling hot/very cold depending on time of year.

I have had three companies come out. The first two sent sales reps who told me a ductless ac/heater system would be best and quoted me 6-8k for the system.

I had a third company come out and the owner himself looked over the house. I found him way more knowledgeable, friendly, and honest than the other two. He suggested we try a few things (booster fan as well as done duct work changes) before enploying a big system. He did say that if it didn't work, I really needed a separate furnace and ac system upstairs. There is plenty of attic access so running new ducts is simple. I live in MN and he said the mini splits he has done perform poorly when it's very cold and he will now only do them if the room gets supplemental heat from the main furnace, which mine doesn't.

I would very much like to work with this guy if it comes down to needing a second system. I'm just worried another furnace and ac system is going to cost me a small fortune. Is the mini split really that bad heat-wise in cold climates?

submitted by /u/kubyx
[link] [comments]