A valve system is provided including a valve seat, an outlet passage and a stop valve. The valve seat has a crenulated portion. The crenulated portion has an annular recess and a plurality of teeth that are separated by a plurality of circumferential gaps. At least one of the teeth has an angled surface that borders between one of the plurality of circumferential gaps and the respective one of the plurality of teeth. The angled surface is oriented at an angle with respect to an axis that extends radially outwardly from a central axis of the valve seat. The outlet passage is located downstream of the valve seat for directing flow out of the valve assembly. The stop valve is located within the annular recess of the crenulated portion.