At the beginning of each day fill the water chamber with Sterile Water for Irrigation, USP. The pump should have been left in a ready condition, see instruction sheet entitled (N2 Tank Replacement and 12 hr High and Low Pressure Testing). The High pressure gauge (0 to 3000psi) should read between 100 and 1900psi; The Low pressure gauge (to 30psi) should read 15psi (+ or- 2psi). Adjust low pressure with brass "T" handle on regulator. Clockwise rotation of the "T" handle raises the pressure, counter clockwise lowers the pressure. Note, you may have to attach and release nitrogen line to top of water chamber a number of times to get the low pressure to come down. After water flow has been established through all transducers disconnect nitrogen line from water chamber until patient arrives for study. Reattach at the beginning of the study. Disconnect the nitrogen line between each patient and discard water at end of day. Do not leave nitrogen line connected to water chamber for extended periods of none functional time. This is the main cause for out gassing or bubbles on your infusion system. Store water chamber inverted on a towel, with lid removed. Leave nitrogen tank valve open as described in instruction sheet entitled (N2 Tank Replacement and 12 hr High and Low Pressure Testing)