PLSS Feedwater Diverter Valve, H2O Shutoff Valve, and Primary Oxygen Shutoff Valve
Copyright 2007 by Eric M. Jones. All rights reserved.
Last revised 9 June 2007.
The PLSS feedwater diverter valve and the other two are on the righthand, front corner of the bottom of the PLSS. The diverter valve allows the astronaut to select Minimum, Intermediate, or Max cooling. Settings between the detents would also work.
Detail from PLSS component diagram shows the valves in a cluster at the bottom, righthand corner of the front of the PLSS. The valve controls have different shapes and are separated by barriers to make it relatively easy to distinguish them by feel, even when wearing the bulky gloves. From the astronaut's right to left, the valve controls are the diverter valve, H2O shutoff, and O2 shutoff.
Valve cluster on a full-scale engineering model at NASA Johnson, showing the barrier plates separating the switches.
Detail from AS11-40-5868, showing the valve cluster on the bottom of Buzz Aldrin's PLSS as he is about to jump down off the bottom rung of the ladder.
Detail courtesy Ulli Lotzmann.