Abstract: A device for spraying a fluid onto a wall of an enclosure (e.g. a toilet bowl) is disclosed. The device includes a fluid container, a fluid sprayer through which the fluid can be sprayed onto the wall of the enclosure, a fluid conduit, a pumping apparatus for delivering fluid from the container through the fluid conduit and to the fluid sprayer, a sensor for detecting the presence of an object near an opening of the enclosure, and a controller in electrical communication with the pumping apparatus and the sensor. The controller activates the pumping apparatus for delivering fluid from the container to the fluid sprayer if the controller determines that an object is not near the sensor. The sensor can include a pyroelectric sensing element and a lens positioned such that a sensor footprint image is focused onto the pyroelectric sensing element.