Patent attributes
A valve comprising a controller; a heater; and two temperature transducers. The controller sends a close signal to the actuator and records a first temperature signal from the first temperature transducer, then controls the heater to attain a first temperature set point at the second temperature transducer. The controller records a time or an amount of energy required to attain the first temperature set point, then sends an open signal. The controller records a second temperature, controls the heater to attain a second set point at the second transducer, and records a time or an energy required to attain the second temperature set point. The controller classifies a fluid inside based on the first value and a flow rate of the fluid through the fluid path based on the second value.