Patent ID: 6929038

Claim:
A volatile liquid underground storage tank pressure reduction system for reducing the volume of vapor recovered during the refueling of a vehicle tank and returned to an underground storage tank in a service station environment, comprising: an underground storage tank; a conduit having an inlet port and an outlet port, wherein said outlet port is connected to said underground storage tank; a fuel dispenser, comprising: a nozzle. a hose connected to said nozzle; a fuel delivery line that couples to said hose and to said underground storage tank to deliver said liquid fuel through said hose and nozzle to the vehicle fuel tank; a vapor pump; a vapor return line contained within said hose that connects to said inlet port of said conduit; a valve connected inline to said conduit, said valve having a valve inlet and a valve outlet; a heat exchanger connected inline to said conduit downstream said valve outlet; an electronic controller electrically coupled to said valve to control the opening of said valve and electronically coupled to said vapor pump to activate said vapor pump, wherein said electronic controller is adapted to open said valve and activate said vapor pump to recover vapor expelled from the vehicle tank dining refueling to pass the vapor through said inlet port and through said heat exchanger to cool the vapor and return the cooled vapor through said outlet port to said underground storage tank; and a heat exchanger temperature sensor that measures the temperature of the vapor leaving said heat exchanger and inputs the temperature into said electronic controller.