Cold button doesn't work
The hot and warm buttons work, but the cold button does not.
This is a well-known problem that I have as well. I am not interested in taking it apart to fix/replace the thermostat to solve the problem of the cold water tube icing up and clogging, so I am trying a fix mentioned in another ifixit forum where I hook up a programmable timer that turns the unit on/off every hour or so. Hour on, hour off, hour on, hour off. I'll let you know how it works!