Abstract: A backflow preventer includes an inlet and an outlet positioned in a stacked configuration with respect to the inlet, the outlet positioned downstream of the inlet with respect to a flow path in which fluid flows from the inlet to the outlet. The backflow preventer further includes a first check valve located between the inlet and the outlet with respect to the flow path, and a second check valve located between the first check valve and the outlet with respect to the flow path. The backflow preventer includes a coupling portion providing fluid communication between the inlet and the outlet, and a diverter positioned between the inlet and the outlet. The diverter includes a baffle that inhibits fluid backflow from the outlet to the inlet.

Abstract: A check valve includes a housing having a fluid flow channel therethrough, a valve seat, a clapper, and a pivot link. The clapper is movable between a closed position where the clapper inhibits fluid flow past the valve seat and a fully open position where the clapper permits fluid flow past the valve seat. The pivot link includes a pivot member supported for rotation about a pivot axis, a first arm rigidly connected to the pivot member and coupled to the clapper, and a second arm rigidly connected to the pivot member and coupled to a biasing member. The pivot link transmits a biasing force from the biasing member to the clapper. An effective biasing force that is transmitted to the clapper while the clapper is in the closed position is greater than an effective biasing force transmitted to the clapper while the clapper is in the fully open position.