A system comprising a housing, a printed circuit board and a differential pressure sensor located inside the housing, and first and second male adaptors. The first and second male adaptors respectively extend through first and second openings in the housing. The first male adaptor comprises a proximal end configured to receive a first pipe, a distal end secured to the differential pressure sensor, and an internal fluid conduit for transmitting fluid received from the first pipe to the differential pressure sensor. The second male adaptor comprises a proximal end configured to receive a second pipe, a distal end secured to the differential pressure sensor, and an internal fluid conduit for transmitting fluid received from the second pipe to the differential pressure sensor. The differential pressure sensor is configured to determine a pressure differential between fluid received via the first male connector and fluid received via the second male connector.