I have a 12k Fujitsu that is in my ~320sf finished attic outside of Boston. There is also another 50sf of storage space/unfinished. Attic has open cell spray foam (now a no-no), but at the time it was offered. I have humidity pushing 65-70% at 70F, and am wondering if there are any solutions. Would replacing the head with a 7K solve the problem? It’s hooked up to a Fujitsu Multi 24k non-hyper heat, with another 12K head attached on the main floor which works great.

Or is the easiest solution to just throw a de-humidifier up there?

Thanks.