Blower timing system for a gas fireplace

Abstract

Systems and methods for control of a heating appliance blower that provide improved the transfer of heat generated in the heating appliance. By automatically timing when the heating appliance blower turns ON and OFF, the heat generated by the heating appliance can be more effectively transferred away from the heating appliance as desired by a user, for example, to improve heating efficiency of the heating appliance.

1 . A blower system for use with a heating appliance, the heating appliance including a heat generating unit, the system comprising: 
 a blower; and    a blower timing control module configured to monitor an ON/OFF state of the heat generating unit and control an ON/OFF state of the blower in response to the monitored ON/OFF state of the heat generating unit, wherein the blower timing control module turns the blower OFF after a first predetermined time period from when an OFF state of the heat generating device is detected.    
   
   
       2 . The system of  claim 1 , wherein the blower timing control module turns the blower ON after a second predetermined time period from when an ON state of the heat generating unit is detected.  
   
   
       3 . The system of  claim 1 , wherein the heat generating unit includes a gas valve, and the blower timing system is configured to monitor ON/OFF signals received by the gas valve as part of monitoring an ON/OFF state of the heating appliance.  
   
   
       4 . The system of  claim 1 , wherein the heating appliance is a fireplace, the fireplace comprising an outer enclosure and a combustion chamber enclosure positioned within the outer enclosure, and at least a portion of the heat generating unit is positioned within the combustion chamber enclosure.  
   
   
       5 . The system of  claim 2 , wherein the blower timing control module delays turning ON the blower at least 2 minutes after the ON state of the heating appliance is detected.  
   
   
       6 . The system of  claim 2 , wherein the blower timing control module delays turning ON the blower about 1 to about 15 minutes after the ON state of the heating appliance is detected.  
   
   
       7 . The system of  claim 1 , wherein the blower timing control module delays turning OFF the blower at least 2 minutes after the OFF state of the heating appliance is detected.  
   
   
       8 . The system of  claim 1 , wherein the blower timing control module delays turning OFF the blower about 1 to about 20 minutes after the OFF state of the heating appliance is detected.  
   
   
       9 . The system of  claim 1 , wherein the heating appliance further includes at least one sensor configured to determine the state of a flame in the heating appliance and generate a flame signal, and the blower timing control module controls the ON/OFF state of the blower based at least in part on the flame signal.  
   
   
       10 . The system of  claim 1 , wherein the blower timing control module includes an analog-to-digital converter to convert a voltage reading indicative of a state of the heat generating device to a digital control signal.  
   
   
       11 . The system of  claim 1 , wherein the blower timing control module monitors the ON/OFF state of the heat generating unit by determining a voltage applied to a main burner valve of the heat generating unit at regular time intervals within the first predetermined time interval.  
   
   
       12 . The system of  claim 11 , wherein the voltage is above a minimum threshold value that enhances noise immunity of the ON/OFF state.  
   
   
       13 . The system of  claim 2 , wherein the blower timing control module monitors the ON/OFF state of the heat generating unit by determining a voltage applied to a main burner valve of the heat generating unit at regular time intervals within the first and second predetermined time intervals.  
   
   
       14 . A method of controlling air flow in a heating appliance, the heating appliance including a combustion chamber, a blower, and a heat generating device, the method comprising: 
 turning ON the heat generating device;    turning ON the blower;    turning OFF the heat generating device; and    turning OFF the blower a first predetermined time period after the heat generating device is turned OFF.    
   
   
       15 . The method of  claim 14 , further comprising turning ON the blower after a second predetermined time period after the heat generating device is turned ON.  
   
   
       16 . The method of  claim 14 , wherein the first and second predetermined time periods are each in the range of about 2 to about 15 minutes.  
   
   
       17 . The method of  claim 14 , wherein the first and second predetermined time periods are each at least 2 minutes.  
   
   
       18 . The method of  claim 14 , further comprising monitoring the ON/OFF state of the heat generating device during the first predetermined time period and aborting the first predetermined time period in the event the heat generating device is turned ON.  
   
   
       19 . The method of  claim 18 , wherein aborting the first predetermined time period includes resetting to zero a timing device whereon the first predetermined time period is monitored.  
   
   
       20 . The method of  claim 15 , further comprising monitoring the ON/OFF state of the heat generating device during the second predetermined time period and aborting the second predetermined time period in the event the heat generating device is turned OFF.  
   
   
       21 . The method of  claim 20 , wherein aborting the second predetermined time period includes resetting to zero a timing device whereon the second predetermined time period is monitored.  
   
   
       22 . The method of  claim 14 , further comprising varying a blower speed during the first and second predetermined time periods.  
   
   
       23 . A fireplace, comprising: 
 a heat generating device;    a combustion chamber enclosure defining a combustion chamber wherein heat is generated with the heat generating device;    a blower configured to create an air flow in the fireplace; and    a blower control module configured to monitor an ON/OFF state of the heat generating device and automatically control an ON/OFF state of the blower in response to the monitored ON/OFF state of the heat generating device;    wherein the blower control module turns OFF the blower after a first predetermined time period from when the heat generating device is turned OFF.    
   
   
       24 . The fireplace of  claim 23 , wherein the blower control module turns ON the blower after a second predetermined time period from when the heat generating device is turned ON.  
   
   
       25 . The fireplace of  claim 23 , wherein the control module monitors the heat generating device during the first predetermined time periods.  
   
   
       26 . The fireplace of  claim 23 , wherein the heat generating device includes a burner, a gas valve, and an ignition system, and the control module monitors at least one of the ignition system function, an open/closed state of the valve, and the presence of a flame at the burner to determine the ON/OFF state of the heat generating device.  
   
   
       27 . The fireplace of  claim 23 , wherein the heat generating device includes a gas valve, and the control module monitors the presence of a control voltage received by the gas valve to determine the ON/OFF state of the heat generating device.