Patent ID: 6898552

Claim:
An electronic plumbing device for controlling the flow of water through the electronic plumbing device, said device comprising: a water valve operable between open and closed positions to control the flow of water through said device, said water valve normally in the closed position to block the flow of water; said water valve including a solenoid to open the water valve and to permit the flow of water through said device when the solenoid is energized; a relay to be selectively energized to supply electrical power to said solenoid; a detector to detect the presence of a user near the device and to develop a detector signal indicative of the presence of a user; a microprocessor, said microprocessor in communication with said detector and with said relay, said microprocessor causing the relay to be energized upon determining that said detector has developed said detector signal; a first timer in said microprocessor for timing a first predetermined time interval representative of a minimum run time, said microprocessor terminating the energization of the relay to return the water valve to the closed position at end of the longer of when said detector signal ceases or said minimum run time; and a second timer in said microprocessor for timing a second predetermined time interval, said microprocessor causing the relay to be energized to supply electrical power to said solenoid and to open the water valve and permit water flow through said device at the end of the second predetermined time interval after energization of the relay was terminated for a minimum run time to flush any water remaining in the device from a prior activation of said device.