Method and system of preheating

Abstract

A method and system of heating combustion air before the combustion air is received by a hot water or steam boiler. A solar panel oriented to receive radiant energy from the sun is used to heat a fluid. A circulating pump moves the hot fluid through a closed loop to a preheat exchanger that is located in the combustion air stream of the hot water or steam boiler. When the combustion air blower of the hot water or steam boiler is on, heat from the heated circulating fluid in the preheat exchanger is transferred to combustion air going through the preheat exchanger to the combustion air blower of the boiler and to the boiler.

1 . A system for heating combustion air before the combustion air is received by a combustion air boiler of a hot water or steam boiler comprising:
 a solar panel oriented to receive radiant energy from the sun for heating a fluid;   a circulating pump for moving heated fluid from said solar panel through a closed loop; and   a preheat exchanger coupled to said closed loop to receive said heated circulating fluid to transfer heat from the circulating fluid to combustion air going to a combustion air blower, a combustion air damper and a boiler.   
     
     
         2 . The system of  claim 1  wherein said preheat exchanger is a fluid-to-air heat exchanger. 
     
     
         3 . The system of  claim 2  wherein said preheat exchanger is located downstream of said combustion air blower. 
     
     
         4 . The system of  claim 1  wherein said combustion air damper controls the amount of combustion air that is delivered to the boiler. 
     
     
         5 . The system of  claim 2  further comprising:
 a first damper coupled to said solar panel to selectively block sunlight from said solar panel. 
 
     
     
         6 . The system of  claim 2  further comprising:
 a second damper located upstream of the preheat exchanger to control the amount of cold air that flows through the preheat exchanger. 
 
     
     
         7 . The system of  claim 5  further comprising:
 a temperature sensor coupled to close the first damper when the heated fluid from said solar panel reaches a preset temperature. 
 
     
     
         8 . The system of  claim 7  further comprising:
 a photo cell coupled to turn off power to the pump when said solar panel is nor receiving sunlight. 
 
     
     
         9 . The system of  claim 8  further comprising:
 an expansion tank coupled to the closed loop. 
 
     
     
         10 . The system of  claim 9  further comprising:
 a combustion air motorized damper for controlling the amount of air that passes through the preheat exchanger. 
 
     
     
         11 . The method of heating combustion air before the combustion air is received by a combustion air blower of a hot water or steam boiler comprising:
 orienting a solar panel to receive radiant energy from the sun for heating a fluid;   providing a circulating pump for moving heated fluid from said solar panel through a closed loop; and   coupling a preheat exchanger to said closed loop to receive said heated circulating fluid to transfer heat from the circulating fluid to combustion air going to a combustion air blower, a combustion air damper, and a boiler.   
     
     
         12 . The method of  claim 11  wherein said preheat exchanger is a fluid-to-air heat exchanger. 
     
     
         13 . The method of  claim 12  wherein said preheat exchanger is located downstream of said combustion air blower. 
     
     
         14 . The method of  claim 11  wherein said combustion air damper controls the amount of combustion air that is delivered to the boiler. 
     
     
         15 . The method of  claim 12  further comprising:
 coupling a first damper to said solar panel to selectively block sunlight from said solar panel. 
 
     
     
         16 . The method of  claim 12  further comprising:
 providing a second damper upstream of the preheat exchanger to control the amount of cold air that flows through the preheat exchanger. 
 
     
     
         17 . The method of  claim 15  further comprising:
 providing a temperature sensor to close the first damper when the heated fluid from said solar panel reaches a preset temperature. 
 
     
     
         18 . The method of  claim 17  further comprising:
 providing a photo cell to turn off power to the pump when said solar pane is nor receiving sunlight. 
 
     
     
         19 . The method of  claim 18  further comprising:
 connecting an expansion tank to the closed loop. 
 
     
     
         20 . The method of  claim 19  further comprising:
 providing a combustion air motorized damper for controlling the amount of air that passes through the preheat exchanger.