Rheostat

When there is an open circuit in the rheostat, the system will operate at maximum cooling; and when there is a short circuit in the rheostat, the system will operate at maximum heating. To check rheostat, proceed as follows:
1. Check resistance of rheostat with lever at mid position. Resistance should be 1450-1500 ohms.
2. When replacing the rheostat, adjust resistance of rheostat to 1500 ohms with control lever set at its midway position by means of the adjusting screw.