Condensate control device

Abstract

A control device including a condensate sensor to generate a control signal when the condensate sensor detects condensate accumulated in a condensate reservoir has reached a predetermined level wherein the condensate sensor comprises a first sensor pin and second sensor pin coupled to a control section by a first detection sensor component and a second detection sensor component respectively balanced to reduce electrolysis that occurs when the condensate reaches the predetermined level that would otherwise cause the first sensor pin and the second sensor pin to corrode excessively.

What is claimed is: 
     
         1 . A control device including a condensate sensor to generate a control signal when said condensate sensor detects condensate accumulated in a condensate reservoir has reached a predetermined level, said control device comprising an input section coupled to a control section through an AC voltage rectification section, an output section coupled through a control signal generator section to said control section and a condensate sensing input section coupled to said control section. 
     
     
         2 . The control of  claim 1  wherein said input section comprises a first sensor terminal coupled to a first sensor pin and a second sensor terminal coupled to a second sensor pin, said first sensor terminal is coupled to said control section and said AC voltage rectification section and said second sensor terminal is coupled to said control section. 
     
     
         3 . The control device of  claim 2  wherein said first sensor terminal and impedance comprise a first detection sensor component and said second sensor terminal and impedance comprise a second detection sensor component. 
     
     
         4 . The control device of  claim 3  wherein said impedances of said first detector sensor component and said second detector sensor component are balanced relative to each other and the impedance of the condensate or water to reduce or mitigate electrolysis on said first sensor pan and said second sensor pan. 
     
     
         5 . The control device of  claim 4  wherein said impedances of said first detector sensor component and said second detector sensor component are each at least 20 megaohms. 
     
     
         6 . The control device of  claim 5  wherein said impedances of said first detector sensor component and said second detector sensor component are each substantially 30 megaohms. 
     
     
         7 . The control device of  claim 6  wherein said control device is powered by a 24 VAC transformer coupled across said first terminal and said second terminal. 
     
     
         8 . The control device of  claim 3  wherein said first sensor terminal is coupled to said control section and said AC voltage rectification section through an impedance and second sensor terminal is coupled to said control section through an impedance and a field-effect transistor. 
     
     
         9 . The control device of  claim 2  wherein said condensate sensing input section further comprises a second set of condensate sensors. 
     
     
         10 . The control device of  claim 9  wherein a first sensor probe is coupled to a third terminal and a second sensor probe is coupled to a fourth terminal. 
     
     
         11 . The control device of  claim 1  wherein said control signal generator comprises a plurality of branches each coupled between a transistor in said control section and a control switch operated in a first state or position and a second state or position. 
     
     
         12 . The control device of  claim 11  wherein said branches each comprises a first resistor and an LED, a noise snubber including a second resistor and a capacitor and a free wheeling diode. 
     
     
         13 . The control device of  claim 11  wherein said control switch comprises a coil and a single pole/double throw switch element or member movable between a first or closed position and a second or open position to couple a first output terminal or a second output terminal to said control signal generator to receive condensate signals from said condensate sensing input section through said control section when condensate within the condensate reservoir reaches a predetermined level. 
     
     
         14 . The control device of  claim 7  wherein said input section comprises a first terminal coupled to the positive output of the secondary winding of the transformer and a second terminal coupled to the negative or common output of secondary winding of said transformer to supply AC power to said control device. 
     
     
         15 . The control device of  claim 14  wherein said AC voltage rectification section comprises a bridge rectifier including a first pair of diodes and a second pair of diodes coupled across said first terminal and said second terminal. 
     
     
         16 . The control device of  claim 15  wherein said first pair of diodes and said second pair of diodes are coupled between ground and a capacitor coupled to ground. 
     
     
         17 . The control device of  claim 14  wherein said control section comprises an amplifier. 
     
     
         18 . The control device of  claim 17  wherein said amplifier comprises a first resistor coupled to a transistor and a second resistor coupled to the base of said transistor. 
     
     
         19 . The control device of  claim 2  wherein said condensate sensing input section further includes a time delay section to prevent said control device from generating false readings or hunting when the condensate or water level is fluctuating at the predetermined level in the condensate reservoir. 
     
     
         20 . The control device of  claim 7  wherein said control device is installed HVAC and grounded at the same potential of the 24 VAC transformer due to the absence of a center-tap transformer. 
     
     
         21 . The control device of  claim 19  wherein said time delay comprises an RC circuit including a resistor and a capacitor coupled between said resistor and said field-effect transistor and a resistor arranged in parallel between said first resistor and ground.