Water heater including a dip tube

Abstract

A water heater includes a storage tank, a heat source for heating water stored in the storage tank, and a dip tube extending into the tank. The dip tube includes upper and lower ends, a restriction between the upper and lower ends so as to create back pressure in the dip tube above the restriction, the restriction positioned in an upper portion of the storage tank, a lower opening below the restriction for providing cold water to a lower portion of the storage tank, and an upper opening above the restriction for providing cold water to the upper portion of the storage tank due to the first restriction.

1 . A water heater comprising:
 a storage tank;   a heat source for heating water stored in the storage tank;   a dip tube extending into the tank, the dip tube having upper and lower ends, a restriction between the upper and lower ends so as to create back pressure in the dip tube above the restriction, the restriction positioned in an upper portion of the storage tank, a lower opening below the restriction for providing cold water to a lower portion of the storage tank, and an upper opening above the restriction for providing cold water to the upper portion of the storage tank due to the restriction.   
     
     
         2 . The water heater of  claim 1 , wherein the upper opening is one of a plurality of upper openings above the restriction and uniformly distributed around the circumference of the dip tube. 
     
     
         3 . The water heater of  claim 2 , wherein the dip tube further includes a second restriction between the upper end and the lower end so as to create back pressure in the dip tube above the second restriction, and a plurality of second upper openings uniformly distributed around the circumference of the dip tube, the second upper openings positioned above the second restriction for providing water to the storage tank due to the second restriction. 
     
     
         4 . The water heater of  claim 3 , wherein the upper openings each have a first diameter and the second upper openings each have a second diameter different than the first diameter. 
     
     
         5 . The water heater of  claim 3 , wherein the dip tube further includes a longitudinal axis, and wherein center points of the first-mentioned upper openings define a first plane that is substantially perpendicular to the longitudinal axis and center points of the second upper openings define a second plane that is substantially perpendicular to the longitudinal axis. 
     
     
         6 . The water heater of  claim 5 , wherein the first-mentioned upper openings each have a first diameter and the second upper openings each have a second diameter different than the first diameter. 
     
     
         7 . The water heater of  claim 5 , wherein the second upper openings are offset from the first-mentioned upper openings. 
     
     
         8 . The water heater of  claim 7 , wherein the first-mentioned upper openings each have a first diameter and the second upper openings each have a second diameter different than the first diameter. 
     
     
         9 . The water heater of  claim 3 , wherein the dip tube further includes a third restriction between the upper end and the lower end so as to create back pressure in the dip tube above the third restriction and a plurality of third upper openings uniformly distributed around the circumference of the dip tube, the third upper openings positioned above the third restriction for providing water to the storage tank due to the third restriction. 
     
     
         10 . The water heater of  claim 9 , wherein the first-mentioned upper openings each have a first diameter, the second upper openings each have a second diameter different than the first diameter, and the third upper openings each have a third diameter different than the first diameter and the second diameter. 
     
     
         11 . The water heater of  claim 9 , wherein the dip tube further includes a longitudinal axis; and wherein center points of the first-mentioned upper openings define a first plane that is substantially perpendicular to the longitudinal axis, center points of the second upper openings define a second plane that is substantially perpendicular to the longitudinal axis, and center points of the third upper openings define a third plane that is substantially perpendicular to the longitudinal axis. 
     
     
         12 . The water heater of  claim 11 , wherein the first-mentioned upper openings each have a first diameter, the second upper openings each have a second diameter different than the first diameter, and the third upper openings each have a third diameter different than the first diameter and the second diameter. 
     
     
         13 . The water heater of  claim 11 , wherein the second upper openings are offset from the first-mentioned upper openings and the third upper openings are offset from the second upper openings. 
     
     
         14 . The water heater of  claim 1 , wherein the restriction is formed as an insert that is positioned within the dip tube. 
     
     
         15 . The water heater of  claim 1 , wherein the restriction is integrally formed with the dip tube. 
     
     
         16 . The water heater of  claim 1 , wherein the dip tube further includes an insert, an upper tube, and a lower tube, the insert connecting the upper tube to the lower tube; wherein the restriction is formed in the insert; and wherein the upper opening is formed in the upper tube. 
     
     
         17 . The water heater of  claim 1 , wherein the dip tube further includes a second restriction between the upper end and the lower end so as to create back pressure in the dip tube above the second restriction and a second upper opening above the second restriction for providing water to the storage tank due to the second restriction. 
     
     
         18 . The water heater of  claim 17 , wherein the first-mentioned restriction and the second restriction are integrally formed with the dip tube. 
     
     
         19 . The water heater of  claim 17 , wherein the dip tube further includes a third restriction between the upper end and the lower end so as to create back pressure in the dip tube above the third restriction, and a third upper opening above the third restriction for providing water to the storage tank due to the third restriction. 
     
     
         20 . A dip tube for use with a water heater including a storage tank with a lower portion and an upper portion and a heat source for heating water stored in the storage tank, the dip tube comprising:
 an upper end;   a lower end;   a restriction between the upper and lower ends so as to create back pressure in the dip tube above the restriction, the restriction positioned in an upper portion of the storage tank;   a lower opening below the restriction for providing cold water to the lower portion of the storage tank; and   an upper opening above the restriction for providing cold water to the upper portion of the storage tank due to the first restriction.