Abstract: A vacuum relief safety valve includes a housing defining an inner chamber and attached to the suction-side of the swimming pool or spa pump. An air inlet aperture is formed in the housing so as to be open to ambient air. A sealing element is disposed within the housing and biased against the air inlet aperture by a spring so as to effectively seal the inner chamber of the housing from ambient air. When a maximum allowed vacuum level within the pump is exceeded, such as when a swimming pool drain is obstructed, the sealing element moves into the inner chamber and opens the air inlet aperture causing the pump to rapidly lose its prime and enabling removal of the entrapment. Simultaneously, the movement of the sealing element provides electricity to a control circuit which shuts off power to the pump.

Abstract: An adjustable vacuum relief safety valve system includes a housing having first and second shells cooperatively defining an inner chamber in fluid communication with a pump of a pool circulation system. A sealing element within the housing is biased against an air inlet aperture of the housing by a spring so as to seal the inner chamber of the housing from the ambient air. To accommodate for different pumps, the first and second shells of the housing are connected to one another such that the compression of the spring can be altered to adjust for the pump's characteristics. During elevated negative pressure operating conditions, the sealing element is pushed into the inner chamber, permitting ambient air to flow into the inner chamber and the pump, causing the pump to rapidly lose its prime. An electronic circuit may be actuated, via a switch, for shutting off power to the pump.

Abstract: A vacuum relief safety valve includes a housing defining an inner chamber and attached to the suction-side of the swimming pool or spa pump. An air inlet aperture is formed in the housing so as to be open to ambient air. A sealing element is disposed within the housing and biased against the air inlet aperture by a spring so as to effectively seal the inner chamber of the housing from ambient air. When a maximum allowed vacuum level within the pump is exceeded, such as when a swimming pool drain is obstructed, the sealing element moves into the inner chamber and opens the air inlet aperture causing the pump to rapidly lose its prime and enabling removal of the entrapment.

Abstract: A vacuum relief safety valve includes a housing defining an inner chamber and attached to the suction-side of the swimming pool or spa pump. An air inlet aperture is formed in the housing so as to be open to ambient air. A sealing element is disposed within the housing and biased against the air inlet aperture by a spring so as to effectively seal the inner chamber of the housing from ambient air. When a maximum allowed vacuum level within the pump is exceeded, such as when a swimming pool drain is obstructed, the sealing element moves into the inner chamber and opens the air inlet aperture causing the pump to rapidly lose its prime and enabling removal of the entrapment.