Backflow preventer, method to operate a backflow preventer, retrofit kit and monitoring system for at least one backflow preventer

Abstract

Backflow preventer ( 10 ), having a first pressure zone ( 12 ) connected to a second pressure zone ( 13 ), the second pressure zone ( 13 ) connected to a third pressure zone ( 15 ), a first pressure sensor ( 21 ), a second pressure sensor ( 22 ) and a third pressure sensor ( 23 ) configured to measure pressure within the first pressure zone ( 12 ), the second pressure zone ( 13 ), and the third pressure zone ( 15 ), respectively, a shut off valve ( 19 ) positioned downstream of the second pressure zone ( 13 ), a bypass valve ( 28 ) positioned within a bypass ( 27 ) between the first pressure zone ( 12 ) and the third pressure zone ( 15 ), and a controller ( 30 ) configured to actuate the shut off valve ( 19 ) and the bypass valve ( 28 ), receive measurement signals from the pressure sensors ( 21, 22, 23 ), and process the measurement signals in order to determine if the backflow preventer ( 10 ) is properly working or improperly working.

1 . A backflow preventer, having comprising:
 a first check valve connected between a first pressure zone and a second pressure zone of the backflow preventer,   a second check valve connected between the second pressure zone and a third pressure zone of the backflow preventer,   a first pressure sensor assigned to the first pressure zone being configured to measure a first pressure being present within the first pressure zone,   a second pressure sensor assigned to the second pressure zone being configured to measure a second pressure being present within the second pressure zone,   a third pressure sensor assigned to the third pressure zone being configured to measure a third pressure being present within the third pressure zone,   a shut off valve positioned downstream of the second check valve,   a first actuator assigned to the shut off valve being configured to open and close the shut off valve,   a bypass extending between the first pressure zone and the third pressure zone,   a bypass valve positioned within the bypass,   a second actuator assigned to the bypass valve being configured to open and close the bypass valve, and   a controller being configured to:
 automatically close and open the shut off valve and the bypass valve for an automatic testing of the backflow preventer, 
 automatically receive measurement signals from the first pressure sensor, second pressure sensor, and third pressure sensor, and 
 automatically process the measurement signals received from the pressure sensors to determine if the backflow preventer is properly working or improperly working. 
   
     
     
         2 . The backflow preventer as claimed in  claim 1 ,
 wherein the controller is further configured to automatically provide data about the testing of the backflow preventer through a communication interface to at least one database, a monitoring system, or combination thereof.   
     
     
         3 . The backflow preventer as claimed in  claim 2 ,
 wherein the controller is configured to automatically provide the data about the testing of the backflow preventer though the communication interface to a cloud database.   
     
     
         4 . The backflow preventer as claimed in  claim 2 ,
 wherein the communication interface is a wireless communication interface.   
     
     
         5 . The backflow preventer as claimed in  claim 1 , wherein:
 the first pressure zone is an inlet pressure zone of the backflow preventer, the second pressure zone is an intermediate pressure zone of the backflow preventer, and   the third pressure zone is an outlet pressure zone of the backflow preventer.   
     
     
         6 . The backflow preventer as claimed in  claim 5 ,
 wherein the controller is further configured to automatically;   close the shut off valve or keep the shut off valve closed,   measure the first pressure by the first pressure sensor and measure the third pressure by the third pressure sensor, and   detect a properly working shutoff valve when the first pressure is greater than the third pressure, or detect an improperly working shutoff valve when the first pressure is not greater than the third pressure.   
     
     
         7 . A method to operate the backflow preventer of  claim 1 , wherein for testing of the shut off valve positioned downstream of the second check valve, the method comprises:
 closing the shut off valve or keeping the shut off valve closed,   measuring the first pressure by the first pressure sensor and measuring the third pressure by the third pressure sensor, and   detecting a properly working shutoff valve when the first pressure is greater than the third pressure, or detecting an improperly working shutoff valve when the first pressure is not greater than the third pressure.   
     
     
         8 . The method to operate the backflow preventer of  claim 7 , wherein for a testing of the first check valve, method comprises:
 closing the shut off valve or keeping the same shut off valve closed,   measuring the first pressure by the first pressure sensor, and measure measuring the second pressure by the second pressure sensor, and   detecting a properly working first check valve when a difference between the first pressure and the second pressure is larger than a threshold, or detecting an improperly working first check valve when the difference between the first pressure and the second pressure is not larger than the threshold.   
     
     
         9 . The method to operate the backflow preventer of  claim 8 , wherein for a testing of the second check valve, the method comprises:
 closing the shut off valve or keeping the same shut off valve closed,   measuring the second pressure by the second pressure sensor and measuring the third pressure by the third pressure sensor, and   determining a properly working second check valve when a difference between the second pressure and the third pressure is larger than a threshold, or determining an improperly working second check valve when the difference between the second pressure and the third pressure is not larger than the threshold.   
     
     
         10 . The method according to  claim 7 , wherein;
 the bypass valve is closed before and/or kept closed for the testing of the shut off valve and/or for the testing of the first check valve and/or for the testing of the second check valve.   
     
     
         11 . The method to operate the backflow preventer  claim 7 , wherein for a backflow testing of the backflow preventer, the method comprises:
 closing the shut off valve or keeping the shut off valve closed,   measuring the first pressure by the first pressure sensor and measuring the second pressure by the second pressure sensor, and   opening the bypass valve and providing fluid from the first pressure zone to the third pressure zone when a difference between the first pressure and the second pressure is larger than a threshold,   closing the bypass valve   measuring the first pressure by the first pressure sensor and measure the second pressure by the second pressure sensor, and   detecting a properly working backflow preventer when the difference between the first pressure and the second pressure remains unchanged, or detecting an improperly working backflow preventer when the difference the first pressure and the second pressure does not remain unchanged.   
     
     
         12 . A retrofit kit to convert a backflow preventer having a first check valve connected between a first pressure zone and a second pressure zone of the backflow preventer and a second check valve connected between the second pressure zone and a third pressure zone of the backflow preventer into a backflow preventer of  claim 1 , the retrofit kit comprising:
 a first pressure sensor being configured to be connected to the first pressure zone and to measure a first pressure being present within the first pressure zone,   a second pressure sensor being configured to be connected to the second pressure zone and to measure a second pressure being present within the second pressure zone,   a third pressure sensor being configured to be connected to the third pressure zone and to measure a third pressure being present within the third pressure zone,   a shut off valve being configured to be connected to the third pressure zone downstream of the second check valve,   a first actuator being configured to open and close the shut off valve, a bypass unit being configured to provide a bypass extending between the first pressure zone and the third pressure zone and a bypass valve positioned within the bypass,   a second actuator being configured to open and close the bypass valve,   a controller being configured to
 automatically close and open the shut off valve and the bypass valve for an automatic testing of the backflow preventer, 
 automatically receive measurement signals from the first pressure sensor second pressure sensor and third pressure sensor, 
 automatically process the measurement signals received from the pressure sensors to determine if the backflow preventer is properly working or improperly working. 
   
     
     
         13 . The retrofit kit of  claim 12 ,
 wherein the controller configured to automatically provide data about the testing of the backflow preventer through a communication interface to at least one database, a monitoring system, or combination thereof.   
     
     
         14 . A monitoring system for at least one backflow preventer, comprising:
 a first interface, the first interface being configured to receive data from the at least one backflow preventer determined during an automatic testing of the at least one backflow preventer, and   a second interface, the second interface being configured to send data to at least one database.   
     
     
         15 . The monitoring system as claimed in  claim 14 , wherein:
 the first interface is further configured to send data to the at least one backflow preventer to initiate an automatic testing of the at least one backflow preventer, and/or   the second interface is further configured to receive from at least one database on which the automatic testing at least one backflow preventer is initiated.   
     
     
         16 . The backflow preventer as claimed in  claim 3 , wherein the communication interface is a wireless communication interface. 
     
     
         17 . The backflow preventer as claimed in  claim 4 , wherein:
 the first pressure zone is an inlet pressure zone of the backflow preventer,   the second pressure zone is an intermediate pressure zone of the backflow preventer, and   the third pressure zone is an outlet pressure zone of the backflow preventer.