Humidifier control system

Abstract

An example humidifier controller for operation in conjunction with an air conditioning/furnace unit is presented. The humidifier controller may include a control circuit to generate a fan control output for the air conditioning/furnace unit. The fan control output may be equal to a fan control input in response to any of a heating control signal, an air conditioning control signal, and the fan control input being active. Also, the fan control output may be based on a humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive.

What is claimed is: 
     
         1 . A humidifier controller comprising:
 a control circuit to generate a fan control output for an air conditioning/furnace unit;   the fan control output being equal to a fan control input in response to any of a heating control signal, an air conditioning control signal, and the fan control input being active; and   the fan control output being based on a humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive.   
     
     
         2 . The humidifier controller of  claim 1 , the control circuit to enable the humidistat output based on the air conditioning control signal being inactive. 
     
     
         3 . The humidifier controller of  claim 1 , the control circuit to forward the humidistat output to a water solenoid of a humidifier unit to control the water solenoid. 
     
     
         4 . The humidifier controller of  claim 1 , the control circuit comprising a timer circuit to extend an active state of the fan control output for a predetermined period of time in response to the humidistat output transitioning from an active state to an inactive state while each of the heating control signal, the air conditioning control signal, and the fan control input is inactive. 
     
     
         5 . The humidifier controller of  claim 3 , the predetermined period of time being at least three minutes. 
     
     
         6 . The humidifier controller of  claim 1 , wherein:
 the fan control output comprises a first fan control output and a second fan control output;   the first fan control output, when active, causes a fan of the air conditioning/furnace unit to operate at a first speed;   the second fan control output, when active, causes the fan of the air conditioning/furnace unit to operate at a second speed less than the first speed;   the control circuit to cause the first fan control output to be equal to the fan control input in response to any of the heating control signal, the air conditioning control signal, and the fan control input being active; and   the control circuit to cause the second fan control output to be based on the humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive.   
     
     
         7 . The humidifier controller of  claim 1 , wherein:
 the heating control signal comprises a first heating control signal for a first physical zone and a second heating control signal for a second physical zone; and   the heating control signal is active in response to at least one of the first heating control signal being active and the second heating control signal being active.   
     
     
         8 . The humidifier controller of  claim 1 , the control circuit to receive the fan control input, the heating control signal, and the air conditioning control signal from a thermostat unit. 
     
     
         9 . The humidifier controller of  claim 8 , the control circuit to forward the fan control input, the heating control signal, and the air conditioning control signal to the air conditioning/furnace unit. 
     
     
         10 . The humidifier controller of  claim 1 , the control circuit comprising:
 a first electronic switch activated by the heating control signal;   a second electronic switch activated by the air conditioning control signal;   a third electronic switch activated by the fan control input;   a first relay activated by any of the first electronic switch, the second electronic switch, and the third electronic switch to relay an internal relay control signal based on the humidistat output; and   a second relay controlled by the internal relay control signal, the second relay to relay the fan control input to the fan control output in response to the internal relay control signal being inactive, and the second relay to activate the fan control output in response to the internal relay control signal being active.   
     
     
         11 . The humidifier controller of  claim 10 , the control circuit comprising:
 a third relay activated by the second electronic switch to provide a humidistat enable signal.   
     
     
         12 . A method of providing humidifier control, the method comprising:
 receiving a heating control signal, an air conditioning control signal, and a fan control input for an air conditioning/furnace unit from a thermostat unit;   receiving a humidistat output from a humidistat; and   generating a fan control output for the air conditioning/furnace unit, the fan control output being equal to the fan control input in response to any of the heating control signal, the air conditioning control signal, and the fan control input being active, and the fan control output being based on the humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive.   
     
     
         13 . The method of  claim 12 , further comprising:
 enabling the humidistat output based on the air conditioning control input being inactive.   
     
     
         14 . The method of  claim 12 , further comprising:
 generating a water solenoid control signal equal to the humidistat output.   
     
     
         15 . The method of  claim 12 , further comprising:
 extending an active state of the fan control output for a predetermined period of time in response to the humidistat output transitioning from an active state to an inactive state while each of the heating control signal, the air conditioning control signal, and the fan control input is inactive.   
     
     
         16 . The method of  claim 12 :
 the fan control output comprising a first fan control output and a second fan control output;   the first fan control output, when active, causing a fan of the air conditioning/furnace unit to operate at a first speed;   the second fan control output, when active, causing the fan of the air conditioning/furnace unit to operate at a second speed less than the first speed; and   the method further comprising:
 causing the first fan control output to be equal to the fan control input in response to any of the heating control signal, the air conditioning control signal, and the fan control input being active; and 
 causing the second fan control output to be based on the humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive. 
   
     
     
         17 . A humidifier controller comprising:
 an input interface to receive, from a thermostat unit, a heating control signal, an air conditioning control signal, and a fan control input for an air conditioning/furnace unit;   an output interface to provide a fan control output for the air conditioning/furnace unit;   a humidistat interface to provide a humidistat enable signal to a humidistat, and to receive a humidistat output from the humidistat; and   a control circuit to generate the fan control output for the air conditioning/furnace unit, the fan control output being equal to the fan control input in response to any of the heating control signal, the air conditioning control signal, and the fan control input being active, and the fan control output being based on the humidistat output in response to each of the heating control signal, the air conditioning control signal, and the fan control input being inactive.   
     
     
         18 . The humidifier controller of  claim 17 , the control circuit to generate the humidistat enable signal based on the air conditioning control signal being inactive. 
     
     
         19 . The humidifier controller of  claim 17 , the control circuit comprising:
 a first electronic switch activated by the heating control signal;   a second electronic switch activated by the air conditioning control signal;   a third electronic switch activated by the fan control input;   a first relay activated by any of the first electronic switch, the second electronic switch, and the third electronic switch to relay an internal relay control signal based on the humidistat output;   a second relay controlled by the internal relay control signal, the second relay to relay the fan control input to the fan control output in response to the internal relay control signal being inactive, and the second relay to activate the fan control output in response to the internal relay control signal being active.   
     
     
         20 . The humidifier controller of  claim 19 , the control circuit further comprising:
 a third relay activated by the second electronic switch to generate the humidistat enable signal.   
     
     
         21 . The humidifier controller of  claim 17 , further comprising:
 a humidifier interface to provide the humidifier output to a water solenoid of a humidifier unit to control the water solenoid.