I did a load of towels and had the machine set to hot water, no dry,
and white cottons. The cycle appeared to complete fine, the door
became unlocked, and I removed the towels and hung to dry.

I then put in a load of a couple of sweaters, set the temp to cold
water, kept it on no drying, and set to delicate cycle. I closed the
door and pressed start. When I came back into the room a few minutes
later, I noticed that the washer appeared to be heating up and
steaming, almost like I'd imagine if it were going into a drying cycle
(even though there hadn't been one set).

In any case, I couldn't get the machine to stop, so I finally just
shut off the power. The door eventually unlocked and there is a
remaining pool of water inside the machine. I left it unplugged for
several hours, hoping it would reset itself. Every time I plug it
back in, the controls remain unresponsive, but it starts to heat up
steam again. I finally thought it was just stuck in the middle of
some cycle it thought it was going through, so I let this run for
another 3 hours - no changes and the water remains.

Hotpoint's website says that the spin cycle won't engage if the
container is unbalanced, so I put in some old towels and plugged it
back in.. same results.

So my questions: (1) is there a way to hard-reset the machine?
Unplugging for several hours doesn't appear to do it; (2) has anyone
else experienced this? (3) Any guesses what might be wrong, or should
I just call repair?

thanks in advance!