A valve apparatus comprising: a first valve seat; a second valve seat substantially co-aligned with the first valve seat; a first valve member movable relative to the first valve seat between at least an open position in which the first valve member is spaced from the first valve seat and a closed position in which the first valve member is seated against the first valve seat; a second valve member substantially co-aligned with the first valve member, the second valve member movable relative to the second valve seat between at least an open position in which the second valve member is spaced from the second valve seat and a closed position in which the second valve member is seated against the second valve seat; and a coil; an armature operable for moving the first valve member and second valve member in response to a magnetic filed generated by the coil; a pressure sensing apparatus; characterized by the armature being configured to move a first distance to move the first valve member away from the closed position against the first valve seat towards the open position, and to move beyond the first distance so as to also then move the second valve member away from the closed position against the second valve seat and towards the open position; the pressure sensing apparatus being configured to provide an output voltage indicative of pressure at an outlet of the valve apparatus; and a controller coupled to the pressure sensing apparatus and the coil, wherein the controller is configured to determine a sensed pressure from the output voltage of the pressure sensing apparatus and to adjust the application of input voltage to the coil based on the sensed pressure, to thereby operate the armature to move the first distance to move the first valve member between the closed and open positions of the first valve member, and to operate the armature to move beyond the first distance to move the second valve member away from the closed position of the second valve member to move the second valve member relative to the second valve seat to vary an extent of an opening area therebetween to achieve multiple, different desired outlet pressures while the opening area is at least partially open. a first valve seat; a second valve seat substantially co-aligned with the first valve seat; a first valve member movable relative to the first valve seat between at least an open position in which the first valve member is spaced from the first valve seat and a closed position in which the first valve member is seated against the first valve seat; a second valve member substantially co-aligned with the first valve member, the second valve member movable relative to the second valve seat between at least an open position in which the second valve member is spaced from the second valve seat and a closed position in which the second valve member is seated against the second valve seat; and a coil; an armature operable for moving the first valve member and second valve member in response to a magnetic filed generated by the coil; a pressure sensing apparatus; the armature being configured to move a first distance to move the first valve member away from the closed position against the first valve seat towards the open position, and to move beyond the first distance so as to also then move the second valve member away from the closed position against the second valve seat and towards the open position; the pressure sensing apparatus being configured to provide an output voltage indicative of pressure at an outlet of the valve apparatus; and a controller coupled to the pressure sensing apparatus and the coil, wherein the controller is configured to determine a sensed pressure from the output voltage of the pressure sensing apparatus and to adjust the application of input voltage to the coil based on the sensed pressure, to thereby operate the armature to move the first distance to move the first valve member between the closed and open positions of the first valve member, and to operate the armature to move beyond the first distance to move the second valve member away from the closed position of the second valve member to move the second valve member relative to the second valve seat to vary an extent of an opening area therebetween to achieve multiple, different desired outlet pressures while the opening area is at least partially open.