An injector for injecting a reagent includes an axially translatable valve member positioned within a housing. An electromagnet is positioned within the housing and includes a coil of wire positioned proximate the valve member such that the valve member moves between a seated position and an unseated position relative to an orifice in response to energizing the electromagnet. A connector coupled to the housing includes an inlet tube concentrically aligned with and surrounding a return tube. The inlet tube is adapted to receive pressurized reagent from a source of reagent. The return tube is adapted to return reagent to the source.