Variable input radiant heater

Abstract

A variable demand radiant heating system applies variable burner control technology to singular or mulit-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 continuously vary gas supply pressure (volume), via a modulating gas regulator, and combustion air pressure (volume), via a variable speed blower, communicated to the burner mixing chamber, which in turn, varies the burner input on a continuous curve (not 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 an elongated heat exchanger;    a burner controller mounted inside the burner housing;    a modulating gas valve, and a burner controller in the burner housing;    the burner controller capable of simultaneously varying gas and combustion air inputs to continuously deliver proper fuel/air ratio at every input rate.    
     
     
         2 . The gas heater of  claim 1  wherein the elongated heat exchanger is configurable in a shape that is straight.  
     
     
         3 . The gas heater of  claim 1  wherein the elongated heat exchanger is configurable in a shape that is U-shaped.  
     
     
         4 . The gas heater of  claim 1  wherein the elongated heat exchanger is configurable in a shape that is selected from the group consisting of straight, U-shaped, J-shaped, L-shaped, and polygonal shaped.  
     
     
         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 modulates 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.  
     
     
         8 . The gas heater of  claim 1  wherein the burner senses burner pressure and automatically adjusts gas and combustion air inputs based on pre-programmed settings for optimum safety, efficiency and performance.  
     
     
         9 . The gas heater of  claim 1  wherein the burner adjusts the speed of a blower to allow combustion air adjustment for flue or vent blockage and/or various inlet flue or vent lengths.  
     
     
         10 . The gas heater of  claim 1  wherein the burner is capable of a 5:1 turndown.  
     
     
         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 continuously 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 energy formed from the combustion of the fuel and the air are vented from the heat exchanger;    a heat demand control device is positioned in the burner housing 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 to satisfy the heat demand;    the controller varies the input of the fuel and the air into the burner housing by being able to simultaneously (1) alter the speed of the blower which controls the air input into the burner assembly and (2) modulate a fuel valve that controls the fuel input into the burner assembly.    
     
     
         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 (1) a pressure switch completes or breaks an electrical circuit due to differential pressure of air in the burner housing and (2) a pressure transducer that measures pressure within the burner housing.  
     
     
         18 . The apparatus of  claim 17  wherein if the values of the pressure switch and the pressure transducer meet a predetermined parameter, the controller allows an air purge period prior to ignition.  
     
     
         19 . The apparatus of  claim 17  wherein if the values of the pressure switch and/or the pressure transducer exceed or are below predetermined parameters, the controller will adjust 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.