To live in Indiana, the humidifier would typically not bother to come on during summer, as nature gives us more humidity than we need. Any time the level of humidity is higher than the selected level, (or max of 45%) the humidifier will not come on.
Some people, just to make sure, will go ahead and turn down the humidistat to 'off' or at least the lowest setting. Then, for the same reasons as listed above, the humidifier will not come on.
Please let us know if you have any further questions.