We moved into this house and it had the aprilaire system installed. We purchased a maintenance kit and installed it. It has a handle with summer, winter, o & c. What does o & c stand for and do you put the handle over the word that you want or point it at it? Thanks for your help.
O & C would indicate Open and Closed. Typically the handle would be over the word indicating the season "winter" during the humidification season and "Summer" during the off months. This is to prevent conditioned air from backflowing into the return side and making sure that all the air flow is directed to the living space.