Apparatus for Controlling a Solid Fuel Forced Hot Air Furnace

Abstract

In a wood pellet fueled forced hot air heating system, a burner is regulated in response to an ambient air, or supply plenum, temperature. The burner regulating means allows for increased burner cycle times. The air handler is regulated in response to a space to be heated, or room, temperature, typically through the use of a mechanical thermostat. The air handler regulating means when used in conjunction with the burner regulating means allows for immediate heat response during a heat call.

What is claimed is:  
     
         1 . A solid fuel, forced hot air heating system, the solid fuel forced hot air heating system comprising:
 a burner means for combusting a solid fuel and providing exhaust gases in response to a burner power signal,   a heat exchanger means for transferring thermal energy from said exhaust gases to an ambient air,   a space thermosensitive means for providing a space temperature feedback in response to the temperature of a space to be heated,   an air handler means for transporting the ambient air to the space to be heated in response to an air handler power signal; and   an air handler regulating means for providing the air handler power signal in response to the space temperature feedback.   
     
     
         2 . The system of  claim 1 , further comprising:
 a means for providing a space temperature setpoint; and   wherein said air handler regulating means, further comprises:
 a means for relating the space temperature feedback and the space temperature setpoint. 
   
     
     
         3 . The system of  claim 1 , wherein said air handler regulating means, further comprises: a thermostat. 
     
     
         4 . The system of  claim 1 , further comprising a thermal compliance means for storing said thermal energy. 
     
     
         5 . A solid fuel, forced hot air heating system, the solid fuel forced hot air heating system comprising:
 a burner means for combusting a solid fuel and providing exhaust gases in response to a burner power signal,   a heat exchanger means for transferring thermal energy from said exhaust gases to an ambient air,   an ambient thermosensitive means for providing an ambient temperature feedback in response to the temperature of the ambient air,   a space thermosensitive means for providing a space temperature feedback in response to the temperature of a space to be heated,   an air handler means for transporting the ambient air to the space to be heated in response to an air handler power signal,   an air handler regulating means for providing the air handler power signal in response to the space temperature feedback; and   a burner regulating means for providing the burner power signal in response to the ambient temperature feedback.   
     
     
         6 . The system of  claim 5 , wherein the ambient thermosensitive means, further comprises: sensing the temperature of a substance that is in thermally communication with the ambient air. 
     
     
         7 . The system of  claim 5 , further comprising:
 a means for providing an ambient temperature setpoint; and   wherein the burner regulating means, further comprises:
 a means for relating the ambient temperature feedback and the ambient temperature setpoint. 
   
     
     
         8 . The system of  claim 7 , wherein the burner regulating means further comprises a PID controller means for relating the ambient temperature feedback and the ambient temperature setpoint over time. 
     
     
         9 . The system of  claim 5 , further comprising:
 a means for providing a low ambient setpoint; and   wherein the air handler regulating means, further comprises:
 a means relating the ambient temperature feedback and the low ambient setpoint. 
   
     
     
         10 . The system of  claim 9 , wherein the means for providing the low ambient setpoint further comprises a thermostatic switch. 
     
     
         11 . A solid fuel, forced hot air heating system, the solid fuel forced hot air heating system comprising:
 a burner means for combusting a solid fuel and providing exhaust gases in response to a burner power signal,   a heat exchanger means for transferring thermal energy from said exhaust gases to an ambient air,   an ambient thermosensitive means for providing an ambient temperature feedback in response to the temperature of the ambient air,   a space thermosensitive means for providing a space temperature feedback in response to the temperature of a space to be heated,   an air handler means for transporting the ambient air to the space to be heated in response to an air handler power signal; and   a furnace regulator switching means for selectively granting control of the burner power signal and the air handler power signal between a continuous operation furnace regulating means and a periodic operation furnace regulating means;   said continuous operation furnace regulating means, comprising:
 a means for providing the burner power signal in response to the ambient temperature feedback; and 
 a means for providing the air handler power signal in response to the space temperature feedback; 
   said periodic operation furnace regulating means, comprising:
 a means for providing the burner power signal in response to the space temperature feedback; and 
 a means for providing the air handler power signal in response to the ambient temperature feedback. 
   
     
     
         12 . The system of  claim 11 , wherein the furnace regulator switching means further comprises a means for calculating a heat load. 
     
     
         13 . The system of  claim 11 , wherein the furnace regulator switching means, further comprises:
 a means for measuring a duration the burner power signal is LOW; and   a means for relating the duration the burner power signal is LOW to a burner low timeout value.   
     
     
         14 . The system of  claim 11 , wherein the furnace regulator switching means, further comprises:
 a means for measuring a duration the burner power signal is HIGH; and   a means for relating the duration the burner power signal is HIGH to a burner high timeout value.   
     
     
         15 . The system of  claim 11 , wherein the furnace regulator switching means, further comprises:
 a means for determining an overheat status.   
     
     
         16 . The system of  claim 11 , wherein the furnace regulator switching means, further comprises:
 an outdoor thermosensitive means for providing an outdoor temperature feedback in response to the temperature of the outdoor air.   
     
     
         17 . The system of  claim 11 , further comprising:
 a means for providing an ambient temperature setpoint,   a means relating the ambient temperature feedback and the ambient temperature setpoint,   a means for providing a space temperature setpoint; and   a means for relating the space temperature feedback and the space temperature setpoint.   
     
     
         18 . The system of  claim 5 , wherein the burner means further comprises:
 a means regulating the speed of a combustion fan in response to the burner power signal.   
     
     
         19 . The system of  claim 5 , wherein the burner means further comprises:
 a means for regulating a flow of the solid fuel in response to the burner power signal.   
     
     
         20 . The system of  claim 5 , wherein the solid fuels is wood pellets.