With a pressure vacuum breaker, however, a drop in the pressure of the water enables the spring to snap the check valve shut. As soon as the water pressure drops, the check valve closes and backflow does not occur.n a pressure vacuum breaker, the water travels through a check valve and causes a poppet to raise up a guide into an air inlet. The air inlet also has a valve which ordinarily remains closed.
Peter Marshall was born Ralph Pierre LaCock on March 30, 1926, to Ralph and Jean LaCock, a show business family, in Huntington, West Virginia. Following his father's death when Marshall was a teenager, he moved to New York City to be with his mother, a costume designer.
PETER JAN SCHOOMAKER was born on 12 February 1946 in Michigan, and was raised in an Army family; was commissioned a second lieutenant through the Reserve Officers Training Corps at the University of Wyoming upon graduation in 1969; entered active duty and attended armor officer basic course at the Armor School, Fort Knox, 1969; completed airborne ...