It’s more important for the harp to be kept in an atmosphere that’s relatively consistent and to be kept regularly tuned. (Don’t tune it up and down.) Harps don’t have to be kept in air conditioned spaces as long as the temperature is comfortable for you and the humidity is between 45 and 70 percent, approximately, as much as possible. We had harps before there was air conditioning, and strings weren’t constantly breaking. My point is I think you should keep it in one place and let it become acclimated to that place, not hauling it back and forth between different climates. It will survive without AC, just as you do. Give it a try. If strings still break, there may be another cause. Just my opinion.