My old washing machine has 4 options (with the highest setting to be "large load"). How can I physically disable the dial in such a way that the large load will no longer be an option for the users?
somewhere in the back there is a pin which limits the rotation of the shaft. move the pin and the number of options will be reduced. (some unknown amount of dissasembly will be required)
or you could add a pin to the back of the knob and cut an arc in the panel to accomodate it.