15.100.590   Visual display.
   Each control switch shall be provided with a visual indicator to verify the position or function of that unit or device. Damper indicators shall indicate damper position. This shall be accomplished by a positive contact on the damper blade. Indicate shall be grouped with the switch.
   All fan indicators shall indicate fan mode. This shall be accomplished by a device(s) located in the air stream that will positively sense the presence or lack of air in the air stream. (Prior code §§ 9.28.1258, 15.13.1312)