Abstract: A fluid sensor (100) senses a level of fluid (20) in a receptacle (10). The fluid sensor comprises a detector assembly (200) for detecting fluid and comprises sensor circuitry. The detector assembly comprises a detector body (201) comprising an electrically insulative material and defining first and second surfaces (210, 220) in a predetermined spaced relation. The detector body defines a space (250) between the first and second surfaces and defines a port (255, 257) for allowing fluid to pass in the space between the first and second surfaces. The detector assembly also comprises first and second conductive layers (212, 222) deposited over at least a portion of the first and second surfaces of the detector body, respectively. The sensor circuitry is conductively coupled to at least one of the first and second conductive layers for generating an electrical signal based on whether fluid is present in the space between the first and second surfaces.