Recently our Hisense DH-70 dehumidifier spilled water all over the kitchen floor. It had run all night, become full, failed to switch itself off, and overflowed. The temporary solution to this was to dump the bucket more often, but that is a hassle. Fortunately the permanent fix is free and fairly simple.
There is a microswitch inside the dehumidifier. It was stuck. It just needed to be poked from the back side. Remove the back cover (a few screws on the back, a couple of screws on the bottom sides corners, pivot the bottom open first, there are clips on top that will break if you just pull!)
Looking at the rear of the machine, on the right side, about where the top of the bucket goes, corresponding to the other side of the wall where the “full” float in the bucket lives, is this switch:
The little metal arm on ours was pushed in (slanted red line). Just touching it with a fingertip was enough to reset the mechanism (straight line).
It looks like this inside, if you have the same problem: A white cylinder poking out into the bucket area, with a black dot in the middle.
This black dot is a plunger, and you should see this when you do not have this problem any more:
The air filters on the side are nice, but they are hardly HEPA filters. Since I pulled both the covers off my unit because nobody has previously posted a guide for this repair that I could find and I needed to see what was happening in there, I took the opportunity to remove the accumulated hair and miscellaneous filth that got past the air filters over the past couple of years:
I recommend you do the same, if you are a handy sort of person. I followed that wiping with a gentle blowing-out using compressed air because some smutz was between the hot and cold coils as well. Gross.
You will know your fix was successful because the bucket will trip its sensor like it used to do, if you did this right. Good luck, and remember that the Jesus loves you