Here’s a log of events to date.
My lack of temperature control is the driver behind the swings. I fixed this last summer using a ton of ice, but I really didn’t want to do that this season. Looks like I may be doing it anyway.
You can see the first few days of the cabinet struggling to keep up as I am adding fresh flower from multiple partial harvests. It stabilizes the morning of the 3rd, after my 907 harvest the night prior dries off a bit. I was concerned with the high vapor pressure differentials at the end of the day, when the cabinet was at maximum temperature with a fixed AH/dewpoint. I decided the morning of the 6th to fix this by either bounding the maximum allowed VPD or changing back to fixed RH regulation for “curing.” Anyway, I bodged up my code making these modifications and didn’t notice until a couple hours later - my humidifier had stuck on. Fortunately, this just wet my filter, so I removed the wet filter and put a new one in, fixed the code bug and we’re running that way since.
Part of me is embarassed to post this, since I expected better results and I’ve been making lots of changes (got rid of some cooling, change control mechanism). In a stable environment this would work much better than it does in my shed, most of these struggles are fighting with the external temperature changing so dramatically. But there it is.