Variable input radiant heater

Abstract

A variable demand radiant heating system applies multi stage burner control technology to singular or multi-burner radiant heating systems. A radiant heater consists of a burner connected to an elongated heat exchanger tube. The combustion air is supplied to the burner via blower or draft inducer. Fuel is supplied to the burner via fuel regulator. Fuel and air are mixed in burner and communicated to the inlet end of the heat exchanger tube. Spent products of combustion are expelled from the heat exchanger at the outlet end. The burner controls provide gas supply pressure (volume), via a multi-stage or modulating gas regulator, and combustion air pressure (volume), via a combustion air blower with a plurality of operating speeds, communicated to the burner mixing chamber, which in turn, varies the burner input between two or more inputs that are stepped or staged within a pre-determined input range as heat demand varies.

1 . A gas-fired radiant tube heater comprising: 
 at least one unitary burner housing connected to at least one heat exchanger;    a fuel outlet that delivers fuel to the burner housing;    a combustion air blower that delivers air to the burner housing;    a controller, in the burner housing, interconnected to the fuel outlet and the combustion air blower, the controller alters the output of the fuel outlet and the output of the combustion air blower, the output for the fuel outlet is a hi setting for high demand heating by providing greater fuel and a lo setting for low demand heating by providing lesser fuel, the output for the combustion air blower is a corresponding hi setting for high demand heating by providing greater air, and a corresponding lo setting for low demand heating by providing lesser air; and    a timing mechanism that switches the settings for the combustion air blower and fuel outlet (1) simultaneously or (2) with a time delay between the setting of(a) one of the combustion air blower and (b) the other the fuel outlet.    
   
   
       2 . The gas heater of  claim 1  wherein the at least one heat exchanger is configurable in a shape that is straight.  
   
   
       3 . The gas heater of  claim 1  wherein the at least one heat exchanger is configurable in a shape that is U-shaped.  
   
   
       4 . The gas heater of  claim 1  wherein the at least one heat exchanger is configurable in a shape that is selected from the group consisting of straight, U-shaped, J-shaped, L-shaped, polygonal shaped and combinations thereof.  
   
   
       5 . The gas heater of  claim 1  wherein the heat exchanger is coupled to heat exchangers of additional heaters and vented through a common exit.  
   
   
       6 . The gas heater of  claim 1  wherein the burner operates at an input within a preset range burner inputs.  
   
   
       7 . The gas heater of  claim 1  wherein the burner input responds to at least one demand control device.  
   
   
       11 . The gas heater of  claim 1  further comprising a blower.  
   
   
       12 . The gas heater of  claim 11  wherein the blower draws air into the heater.  
   
   
       13 . The gas heater of  claim 11  wherein the blower pushes air into the heater.  
   
   
       14 . An apparatus for varying the input of at least one radiant gas heater that responds to heat demand comprising: 
 a burner housing having (1) a combustion air and fuel inlet and (2) a burner assembly for mixing the fuel and air and conveying the mixture into a heat exchanger for combustion;    at least one conduit in conjunction with a blower that directs at least the energy formed from the combustion of the fuel and the air from the burner housing to a heat exchanger;    the gasses formed from the combustion of the fuel and the air are vented from the heat exchanger;    a heat demand control device positioned in the heated space transmits a signal to a controller and based on the signal, the controller varies the input of the fuel and the air into the burner housing between hi settings and lo settings for the input of the fuel and the input of the air to satisfy the heat demand.    
   
   
       15 . The apparatus of  claim 14  wherein the blower provides positive air pressure from the burner end of the heater.  
   
   
       16 . The apparatus of  claim 14  wherein the blower provides negative pressure from the exhaust end of the heater.  
   
   
       17 . The apparatus of  claim 14  further comprising at least one pressure switch that completes or breaks an electrical circuit due to differential pressure of air in the burner housing.  
   
   
       18 . The apparatus of  claim 17  wherein if the air pressure meets a predetermined pressure switch setpoint parameter, the controller allows an air purge period prior to ignition.  
   
   
       19 . The apparatus of  claim 17  wherein if the air pressure does not meet predetermined parameters, the blower will adjust to a higher or lower setting or terminate the flow of air and/or fuel into the burner housing.  
   
   
       20 . The apparatus of  claim 17  wherein the energy generated by the fuel and the air is radiant and convective heat.  
   
   
       21 . The apparatus of  claim 1  wherein additional settings between the high setting and the low setting are optional,