Dual solid chemical feed system

A dual solid chemical feed system, comprising:

• two feed bowls, each containing a quantity of solid chemicals that dissolve upon immersion in water to form a liquid solution;
• a source for supplying water to each bowl;
• a first valve coupled to said water source for controlling the supply of water to one of said bowls, said first valve being in a normally open position to allow flow of water to said one of said bowls;
• a second valve coupled to said water source for controlling the supply of water to the other of said bowls, said second valve being in a normally closed position to prevent flow of water to said other of said bowls;
• a sump for receiving liquid solution from each of said bowls and for containing liquid solution therein at a predetermined level;
• a sensor supported by said sump in communication with liquid solution for sensing the conductivity of said liquid solution and for generating a signal at a predetermined conductivity of said liquid solution;
• and
• a control unit responsive to said signal for closing said first valve, thereby preventing flow of water to said one of said bowls and opening said second valve, thereby allowing flow of water to said other of said bowls.

In a solid chemical feed system for supplying liquid solution containing dissolved chemicals, an apparatus for controlling the conductivity of the liquid solution, comprising:

• at least one feed bowl containing a quantity of solid chemicals that dissolve upon immersion in water to form a liquid solution;
• a sump for receiving said liquid solution from said at least one bowl and for containing such liquid solution therein at a predetermined level;
• a water source;
• a first valve coupled to said water source for controlling the supply of water to said at least one bowl;
• a second valve coupled to said water source for controlling the supply of water to said sump;
• a sensor in said sump in communication with said liquid solution for sensing the conductivity of said liquid solution and for generating a signal at a predetermined conductivity of said liquid solution;
• and
• a control unit responsive to said signal for opening said first valve and closing said second valve to thereby supply water to said feed bowl when said conductivity is below the predetermined conductivity and for closing said first valve and opening said second valve to thereby supply water to said sump when said conductivity is above the predetermined conductivity.