A sensor assembly including a housing having an inlet an outlet and an interior space generally closed from an environment external to the sensor assembly. The interior space of the housing can include an inlet zone, a central zone and an outlet zone. A baffle can be disposed within the central zone of the interior space of the housing and be located between the inlet zone and the outlet zone and nearer to the inlet zone than to the outlet zone. The baffle can extend downwardly from an upper side of the housing. A gas sensor that can be operable to detect a presence of a lower GWP refrigerant can be disposed in the outlet zone of the interior space of the housing. The housing includes a door in a lower side of the housing in the central zone of the housing.