Top Entry Double Check Valve Assembly
The Apollo Series 4A-100 Double Check Valves are designed to prevent contamination of
the potable water supply due to back-siphonage or backpressure from substances that
are objectionable, but non-health hazards. The modular check valve captured spring
cartridges have replaceable seats and reversible silicone seat discs.

OPERATION
During normal flow conditions, the two check valves are held off their seats, supplying
water downstream. Each check valve is designed to maintain a minimum of 7 kPa across
the valve during normal operation. Should the downstream pressure increase to within
7 kPa of supply pressure, both check valves will close to prevent a backflow condition.