Abstract: A vent/vacuum breaker float valve assembly is provided which includes a float sub-assembly that moves a seal into engagement with a vent port seat when liquid enters the body of the valve to seal the inner valve chamber when all the air trapped in the chamber has been exhausted. The valve assembly also includes a poppet valve sub-assembly which closes and remains closed so long as the valve chamber is pressurized. However, when the liquid is removed from the valve chamber both the vent valve and the poppet valve open to the atmosphere to break the vacuum within the chamber and to allow air to replace the draining liquid.