Patent Publication Number: US-11655982-B2

Title: Pellet heater

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 63/185,189 filed May 6, 2021, and is a continuation-in-part of, and claims the benefit of U.S. Nonprovisional application Ser. No. 17/683,152 filed Feb. 28, 2022, and is a continuation-part-of, and claims the benefit of U.S. Nonprovisional application Ser. No. 17/694,097 filed Mar. 14, 2022, the disclosures of which are hereby incorporated by reference herein in their entireties. 
    
    
     FIELD OF THE INVENTION 
     Embodiments of the present invention relate to outdoor heating appliances. 
     BACKGROUND OF THE INVENTION 
     Outdoor socializing has become increasingly popular even when the weather is cool or cold. As a result, families may utilize outdoor heating appliances to keep their outdoor entertaining area warm. A number of different appliances are currently available to heat outdoor spaces. Such appliances require some form of power and/or fuel to generate the heat required, or in some instances to power systems used to ignite and control the combustion of a given fuel. Over the years, the most popular power/fuel source has varied. Historically, popular heat/fuel sources have included electrical heating elements, wood logs and chips, charcoal briquettes, propane gas, natural gas, and more recently biomass pellets. References herein to a “pellet heater” are intended to include all devices that use some form of pelletized (i.e., solid) fuel, whether or not such fuel is technically considered biomass fuel. 
     Biomass pellets have several advantages over other fuel sources for outdoor heating. For one, biomass pellets are relatively easy and safe to transport and store. As compared with charcoal or wood, biomass pellets are also capable of providing a controlled burn rate and level of heat. Still further, biomass pellets may be manufactured to provide a particular “flavor” to the exhaust fumes as a result of combusting a pellet including a particular wood type. For example, a consumer may select hickory, maple, or cherry pellets, or a combination of pellet flavors, to impart a desired fragrance to the exhaust fumes. 
     Existing pellet heaters, however, do have some disadvantages as currently designed. For example, existing pellet heaters typically require a continuous supply of alternating current (AC) power limiting the use of the heater to locations with such power supplies and requiring unsightly power cords. Thus, there is a need for a pellet heater that is untethered to a continuous supply of AC electrical power, such as a battery powered pellet heater. 
     In order to provide a pellet heater untethered to an AC power source, it may be advantageous to reduce the power required to convey solid pellet fuel to the heater burn pot. Accordingly, there is a need also for a pellet heater that provides improved conveyance of fuel pellets from a storage hopper to a combustion area, such as a burn pot by reducing the power required to convey a given mass of pellet to a burn pot, and to power a pellet heater in general. 
     Known pellet heaters utilize a single speed auger motor and short operation duration motor to convey solid fuel pellets to a burn pot, or alternatively, to an exit for replacement or repair. The single speed and/or short duration operation auger motor may take a fairly long time to empty a full pellet hopper. Accordingly, there is a need also for a pellet heater that improves the ease with which a new flavor of pellet can replace an existing flavor of pellet stored in the hopper. 
     Known pellet heaters also provide radiant heat only which limits the area that is heated. Accordingly, there is a need for a pellet heater that employs a forced air system to distributed heated air in a relatively large area around the heater. 
     Outdoor spaces are often lighted and attract insects that are annoyances to a gathering of people. Even in daylight hours, insects may be attracted to an outdoor space. Accordingly, this is a need for a pellet heater that is configured to distribute insect repellant, such as citronella, along with the distribution of heated air. Indeed, such pellet heaters may also be used to distribute scented heated air to provide a pleasant atmosphere for entertaining. Accordingly, there is also a need for a pellet heater that is configured to distribute aromatic agents along with the distribution of heated air. 
     Known pellet heaters require a system for removing the ash that remains after combusting solid pellet fuel. Existing ash removal systems can be messy and cause ash to spill on the ground or underlying surface. Accordingly, there is a need also for a pellet heater that improves the ability and speed of clearing pellet ash from the heater for cleaning purposes. 
     OBJECTS OF THE INVENTION 
     Accordingly, it is an object of some, but not necessarily all embodiments of the present invention to provide a pellet heater that is untethered to a continuous supply of AC electrical power. 
     It is also an object of some but not necessarily all embodiments of the present invention to provide a pellet heater that provides improved conveyance of fuel pellets from a storage hopper to a combustion area, such as a burn pot, by including multiple auger blades for convey of solid fuel. 
     It is also an object of some but not necessarily all embodiments of the present invention to provide a pellet heater that improves the ease with which a new flavor of pellet can replace an existing flavor of pellet stored in the heater hopper by providing for high-speed or longer duration auger motor operation for a pellet replacement procedure. 
     It is also an object of some but not necessarily all embodiments of the present invention to provide a pellet heater that improves the ability to clear all pellets from the heater for cleaning and/or replacement purposes by providing for high-speed or longer auger motor operation for a pellet clean-out procedure. 
     It is another object of some, but not necessarily all embodiments of the present invention to provide a pellet heater that reduces the power required to convey a given mass of pellet to a burn pot, as well as reduces the electrical power requirements, in general, of a pellet heater, by providing a dual auger blade system that conveys solid fuel to a central burn pot location from right and left storage locations. 
     It is another object of some, but not necessarily all embodiments of the present invention to provide a pellet heater that employs a plurality of blowers and associated heat vents in a forced air system to distributed heated air in a relatively large area around the heater. 
     It is another object of some, but not necessarily all embodiments of the present invention to provide a pellet heater that is configured to distribute insect repellant, such as citronella, and/or other pleasant aromatic agents, along with the distribution of heated air. 
     In is another object of the some, but not necessarily all embodiments of the present invention to provide a pellet heater that improves upon the ash removal process by improving upon the burn pot removable base design. 
     SUMMARY OF EMBODIMENTS OF THE INVENTION 
     Responsive to the foregoing challenges, Applicant has developed an innovative pellet fueled heater, comprising: a base housing; an intake housing disposed within the base housing; one or more blowers disposed within the base housing, said one or more blowers connected to the intake housing; one or more heat vents provided in the base housing; a burn pot housing disposed within the intake housing; a burn pot disposed within the burn pot housing; a solid fuel hopper disposed within the base housing; and an auger system disposed within the base housing between the burn pot and solid fuel hopper. 
     Applicant has further developed an innovative pellet fueled heater, comprising: a base housing; an intake housing disposed within the base housing; one or more blowers disposed within the base housing, said one or more blowers connected to the intake housing; one or more heat vents provided in the base housing; a burn pot housing disposed within the intake housing; a burn pot disposed within the burn pot housing; a solid fuel hopper disposed within the base housing; an auger system disposed within the base housing between the burn pot and solid fuel hopper; an outer tube sealed to and extending away from the intake housing through an opening in an upper part of the base housing; and an inner tube disposed within the outer tube, said inner tube sealed to and extending away from the burn pot housing, wherein an outer tube passage is defined between the outer tube and the inner tube, said outer tube passage communicating with an interior of the intake housing, and wherein an inner tube passage is defined by an interior of the inner tube, said inner tube passage communicating with an interior of the burn pot housing. 
     Applicant has still further developed an innovative outdoor solid fuel, gas fuel, or electric powered heater, comprising: a base housing having a bottom wall and four side walls connected in a rectangular shape extending upward from the bottom wall; an intake housing disposed within the base housing; a first blower disposed within the base housing proximal to a first one of said four side walls and connected to the intake housing; a second blower disposed within the base housing proximal to a second one of said four side walls and connected to the intake housing; a first heat vent provided in the base housing proximal to said first blower; a second heat vent provided in the base housing proximal to said second blower; an inner housing disposed within the intake housing; a solid fuel, gas fuel, or electric powered heat source disposed within the inner housing; an outer tube sealed to and extending away from the intake housing through an opening in the base housing; and an inner tube disposed within the outer tube, said inner tube sealed to and extending away from the inner housing, wherein an outer tube passage is defined between the outer tube and the inner tube, said outer tube passage communicating with an interior of the intake housing, and wherein an inner tube passage is defined by an interior of the inner tube, said inner tube passage communicating with an interior of the inner housing. 
     Applicant has still further developed an innovative solid fuel heater, comprising: a base housing; an intake housing disposed within the base housing; one or more blowers disposed within the base housing, said one or more blowers connected to the intake housing; one or more heat vents provided in the base housing; a burn pot housing disposed within the intake housing; a burn pot disposed within the burn pot housing; a solid fuel hopper disposed within the base housing; and a solid fuel supply mechanism disposed within the base housing between the burn pot and solid fuel hopper, wherein each one of said one or more blowers is proximal to and associated with a distinct one of said one or more heat vents. 
     Applicant has still further developed an innovative solid fuel heater, comprising: a base housing having a bottom wall and four side walls connected in a rectangular shape extending upward from the bottom wall; an intake housing disposed within the base housing; a first blower disposed within the base housing proximal to a first one of said four side walls and connected to the intake housing; a second blower disposed within the base housing proximal to a second one of said four side walls and connected to the intake housing; a first heat vent provided in the base housing proximal to said first blower; a second heat vent provided in the base housing proximal to said second blower; a burn pot housing disposed within the intake housing; a burn pot disposed within the burn pot housing; a solid fuel hopper disposed within the base housing; and a solid fuel supply mechanism disposed within the base housing between the burn pot and solid fuel hopper. 
     Applicant has still further developed an innovative solid fuel heater, comprising: a base housing; an intake housing disposed within the base housing; one or more blowers disposed within the base housing, said one or more blowers connected to the intake housing; one or more heat vents provided in the base housing; a burn pot housing disposed within the intake housing; a burn pot disposed within the burn pot housing; a solid fuel hopper disposed within the base housing; a solid fuel supply mechanism disposed within the base housing between the burn pot and solid fuel hopper; an outer tube extending away from the intake housing through an opening in the base housing; and an inner tube disposed within the outer tube, said inner tube extending away from the burn pot housing, wherein each one of said one or more blowers is proximal to and associated with a distinct one of said one or more heat vents, wherein an outer tube passage is defined between the outer tube and the inner tube, said outer tube passage communicating with an interior of the intake housing, and wherein an inner tube passage is defined by an interior of the inner tube, said inner tube passage communicating with an interior of the burn pot housing. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to assist the understanding of this invention, reference will now be made to the appended drawings, in which like reference characters refer to like elements. The drawings are exemplary only and should not be construed as limiting the invention. 
         FIG.  1    is a perspective view of a pellet heater in accordance with embodiments of the invention. 
         FIG.  2    is a cross-sectional side view of a pellet heater in accordance with embodiments of the invention. 
         FIG.  3    is a cross-sectional side plan view of a pellet heater base unit in accordance with embodiments of the invention. 
         FIG.  4    is a cross-sectional side perspective view of a pellet heater base unit in accordance with embodiments of the invention. 
         FIG.  5    is a cross-sectional side perspective view of a pellet heater chimney structure and center housing in accordance with embodiments of the invention. 
         FIG.  6    is a cross-sectional side perspective view of a pellet heater chimney structure and upper cap in accordance with embodiments of the invention. 
         FIG.  7    is a cross-sectional top perspective view of a pellet heater base unit in accordance with embodiments of the invention. 
         FIG.  8    is a cross-sectional side perspective view of a pellet heater base unit in accordance with embodiments of the invention. 
         FIG.  9    is a perspective view of a burn pot base in accordance with embodiments of the invention. 
         FIG.  10    is a perspective view of a dual auger blade and auger shaft assembly in accordance with embodiments of the invention. 
         FIG.  11    is a schematic diagram of a pellet heater electrical system in accordance with embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. With reference to  FIGS.  1 - 2   , a pellet heater  10  may include a lower base unit, including a base housing  100 , and a chimney structure  200 . The base housing  100  may be provided with caster wheels  102  and wheel locks. With reference to  FIGS.  1 - 2  and  7 - 8   , preferably the base housing  100  may have a bottom wall and four side walls connected in a rectangular shape extending upward from the bottom wall. Each of the four side walls of the base housing  100  may have a rectangular bottom portion that transitions to an inwardly slanted trapezoidal upper portion. In addition, an inwardly canted recessed side wall portion may be included as the lower most portion of each of the four side walls, and an elongated vent opening  132  may extend along the majority of the width of each side wall in each recessed side wall portion. The top wall of the base housing  100  may include a large central opening configured to securely receive the chimney structure  200  that extends upward and away from the base housing. The size, shape, and design of the base housing  100  may be varied without departing from the intended scope of the invention. For example, in alternative embodiments, the base housing may have a circular or oval footprint instead of a rectangular footprint as shown. 
     With reference to  FIGS.  1 - 6   , the chimney structure  200  may include a plurality of elongated upwardly extending vertical tubes  210  connected together by a lattice or cage of smaller diameter protective supports  240 . The vertical tubes  210  may be hollow to conceal internal wiring running between a readout panel controller  304  and the base housing  100 . The combination of the vertical tubes  210  and protective supports  240  may support a center housing  300  and an upper cap  400 . The vertical tubes  210  and the protective supports  240  may also surround and protect an outer tube  220  that extends from an intake housing  262  disposed within the base housing  100  at a bottom end to the upper cap  400  at a top end. The outer tube  220  may be made of any suitable heat tolerant material, but preferably of transparent or translucent heat resistant glass or plastic. Preferably the outer tube  220  is not only supported by the intake housing  262 , but is connected thereto and sealed thereto. Optional electrically powered lighting may be supported by the outer tube  220  and/or the combination of the vertical tubes  210  and protective supports  240 . An inner tube  230  may be disposed within the outer tube  220  such that an outer tube passage  260  is defined between the outer tube and the inner tube. In turn, an inner tube passage  250  may be defined by an interior of the inner tube  230 . The inner tube  230  may extend from an inner housing or burn pot housing  245  disposed within the intake housing  262  at a bottom end to the upper cap  400  at a top end. The inner tube  230  also may be made of any suitable heat tolerant material, but preferably of transparent or translucent heat resistant glass or plastic. Preferably the inner tube  230  is not only supported by the inner housing or burn pot housing  245 , but is connected thereto and sealed thereto. 
     With reference to  FIG.  5   , the center housing  300  may be hollow and include an array of mid-station inlet vents  224  on each of its four sides. The center housing  300  may be closely fitted to the outer tube  220 , or even sealed thereto. Mid-station outer tube openings  225  may be provided in the wall of the outer tube  220 . With reference to  FIG.  6   , the upper cap  400  may be hollow and supported by, and preferably connected to, one or more of the vertical tubes  210 , protective supports  240 , and the outer tube  220 . The upper cap  400  may include an array of upper cap air intake vents  420  on each of its four sides and a centrally located exhaust vent  410 . Preferably a sleeve extends between the exhaust vent  410  and the inner tube  230  and provides a seal between the foregoing. The combination of the inner tube  230  and the sleeve work together to isolate the outer tube passage  260  from the inner tube passage  250 . As a result, the inner tube passage  250  communicates exclusively, or nearly exclusively, with the exhaust vent  410 , while the outer tube passage  260  communicates exclusively, or nearly exclusively, with the upper cap intake vents  420  and mid-station inlet vents  224  in terms of fresh air movement into the heater  10 . 
     With reference to  FIGS.  1 - 8   , the outer tube passage  260  may communicate with an interior of the intake housing  262 . Three of the four side walls of the intake housing  262  may have an electrically powered blower  130  (preferably a centrifugal blower) connected thereto. Each blower  130  may be electrically connected to the battery pack  372  and/or the AC receptacle  378 , as well as the readout panel/controller  304 . The intake end of each blower  130  may be sealed to the intake housing  262 , and the exhaust end of each blower may direct air towards an associated and proximal heat vent  132  provided in the base housing  100 . The burn pot housing  245  may isolate the burn pot  242  from the interior of the intake housing  262  so that the hot exhaust fumes from the burn pot pass exclusively upward into the inner tube passage  250  and out of the exhaust vent  410  provided in the upper cap  400 . These hot exhaust fumes may heat the inner tube  230 . When the blowers  130  are engaged, fresh air may be drawn through the upper cap air intakes  420  in the upper cap  400  and through the mid-station air inlet vents  224  into the outer tube passage  260  where it is heated by the inner tube  230 . The incoming fresh air is further heated in the intake housing  262  by virtue of heat transfer through the walls of the burn pot housing  245 . The heated fresh air is then drawn through the blowers  130  and directed through the base housing  100  to the heat vents  132 . Preferably the blowers  130  are of sufficient strength to establish a heated zone of 10 to 15 feet in diameter. The blowers  130  or a portion of the base housing  100  between the blowers and the heat vents  132  may each include a location at which a liquid or solid aromatic dispensing unit may be provided. The aromatic dispensing unit may be the “plug-in” type and may be used to introduce scents, including insect repellant, such as citronella, into the stream of heated air exiting the base housing  100 . 
     While the preferred heat source is a solid pellet fuel burn pot, it is appreciated that one of ordinary skill in the art could alternatively use a different solid fuel, gas fuel, or electric powered, heat source. However, with respect to the preferred pellet fueled heat source, and with reference to  FIGS.  1 - 4  and  7 - 8   , one side wall of the base housing  100  may include an openable pellet hopper door  328 , a battery compartment cover  368 , and an alternating current (AC) receptacle  378 . The battery compartment cover  368  may conceal a battery compartment  370  containing a removeable direct current (DC) battery pack  372 . The battery compartment  370  may also house an optional battery charger (not shown) that is connected to the AC receptacle  378 . The battery compartment  370  and battery pack  372  may be electrically connected to a readout panel/controller  304  which in turn is operatively connected to a control knob  302 . The readout panel/controller  304  and control knob  302  may be provided on or in the center housing  300  provided as part of the chimney structure  200  above the base housing  100 . The readout panel/controller  304  may be wirelessly or plug-in connected to various electrical components in the heater, such as the battery pack  372 , the AC receptacle  378 , an auger motor  348 , an intake fan assembly  140 , the blowers  130 , a Resistance Temperature Detector (RTD)  402 , and a spark generator  360 , which are discussed in more detail below. 
     With continued reference to  FIGS.  1 - 4  and  7 - 8   , the pellet hopper  310  may be provided within the base housing  100  adjacent to the hopper door  328 . The pellet hopper  310  may taper inwardly from top to bottom to promote the flow of pellets in a downward direction under the influence of gravity. An example of the inward taper of the pellet hopper  310  is readily visible from  FIG.  2   . The hopper  310  may be used to store different types of solid fuel, preferably solid pellet fuel. The bottom end of the hopper  310  may be open so that fuel pellets may drop from the hopper into a dual blade auger  340  disposed within a tube-shaped auger housing  350 . The auger  340  may be configured to convey fuel pellets inwardly from opposing (left side and right side) ends of the hopper  310  to a pellet feed tube  332  located near or at the center of the hopper. The pellet feed tube  332  may be inclined downward and inward (i.e., towards the center of the base housing  100 ) through the walls of the intake housing  262  and the burn pot housing  245  to the burn pot  242 . The burn pot  242  may include a number of openings  244  to provide air flow from the interior of the burn pot housing  245  housing to the interior of the burn pot  242 . 
     With reference to  FIGS.  2 - 4 ,  7 - 8  and  10   , the auger  340  may have a left auger blade  342  and a right auger blade  344  set with opposing blade angles or pitches. The respective left and right auger blades,  342  and  344 , may be configured to convey pellets inwardly from opposing (left side and right side) ends of the hopper  310  to the pellet feed tube  332  located near or at the center of the hopper. More specifically, the left auger blade  342  and the right auger blade  344  may have a colinear axis of rotation, and the two auger blades convey solid fuel pellets in different directions, preferably in opposite directions taken relative to a common reference line. The left and right auger blades,  342  and  344 , may be connected to a single auger shaft  345 , which in turn connects the two auger blades. An auger center piece  343  may have one or more pins having a central axis extending away from the auger shaft in an orthogonal direction. The auger  340  may be supported by one or more auger bearings  346  and be partially encased by the auger housing  350  defining a passage extending between the bottom end of the hopper  310  and the pellet feed tube  332 . 
     The auger motor  348  may drive the auger  340  at various predetermined speeds and/or for various durations under the control of the readout panel/controller  304  (shown in  FIG.  1   ). The auger motor  348  may drive the auger  340  at one or more predetermined speeds and/or predetermined durations to provide a desired amount of fuel based on measured temperatures. Temperature measurements may be taken using the RTD  402  positioned as needed in the base housing  100  and/or the chimney structure  200 . By using the dual auger  340 , less power may be consumed by the auger motor  348  to convey a given mass of pellet fuel because the pellets are nearer the feed tube  332  than is the case with alternative solid fuel supply mechanisms, and because the pellets only need to be conveyed a short distance from opposing sides of the hopper to a central feed tube. This design also may be used to conduct a pellet replacement operation and/or a pellet hopper cleaning operation using the auger  340  system. By removing the burn pot base  254  (discussed below) solid fuel pellets may be conveyed from the hopper  310  through the pellet feed tube  332  and out of the bottom of the burn pot  242  to a receptacle (not shown). Still further, under the control of the readout panel/controller  304 , the auger motor  348  may be able to run continuously and/or at a relatively higher speed to quickly evacuate all pellets from the pellet hopper/compartment(s) for pellet clean-out operations and/or pellet replacement operations as compared with the rotational duration and/or speed of the auger motor for normal burn operation. For example, such clean-out operations may result from running the auger motor  348  continuously at least two to three times the speed than as for burn operation, or even tens of RPMs faster than for burn operation. Preferably, the clean-out operation speed of the auger motor  348  is continuous running in the range of 1.5 to 4 RPMs greater than as for heater burn operation. In some embodiments, the higher clean-out speed may be selectively controlled by the user using the readout panel/controller  304  or some other control device. 
     With reference to  FIGS.  1 - 3  and  7 - 8   , the burn pot  242  may be connected to a fan assembly  140  disposed within the base housing  100 . The fan assembly  140  may be used to draw air through one of the heat vents  132  and thereafter direct the air to the burn pot housing  245  and the burn pot  242 . A Resistance Temperature Detector (RTD)  402  also may be mounted within the interior of the base housing  100 . 
     With reference to  FIGS.  1 ,  3 ,  8  and  9   , the base housing may include two opposing flanges, rails or tracks  252  configured to slidingly receive a removeable burn pot base  254 . The flanges  252  may be provided so that the burn pot base  254  may slide forward and away from the base housing  100 . The burn pot base  254  may have a forward portion with a raised surface that is essentially flush with the bottom of the base housing  100 , and a rear portion with a depression that is configured to collect ash as the burn pot base is pulled forward. Additionally, the depression may be used to hold aromatics, such as citronella. The burn pot base  254  may be removed for solid fuel ash clean-out, or unburned solid fuel clean-out/replacement. During a pellet removal process, the auger  340  may be run at high speed or longer duration under the control of the readout panel/controller  304 . Specifically, a method of solid fuel clean-out operation may involve the steps of providing solid fuel in the hopper  310 , removing the burn pot base  254 , and rotating the auger blades at a longer duration and/or higher speed than is used for heater burn operation in order to convey solid fuel from the hopper through the open bottom of the burn pot  242  for the clean-out operation. 
     With reference to  FIGS.  3  and  7   , an AC and/or DC powered dual ignitor or electrode  364  may extend through the walls of the burn pot  242  into the interior of the burn pot. The electrode  364  may include two tips separated by an air gap across which a continuous spark may be provided to ignite pellets in the burn pot  242 . The electrode  364  may be retained in place using a pressure fit with the burn pot  242  or other fastening means. The dual igniter  364  may include first and second electrodes that may each include a metallic tip extending away from a surrounding ceramic insulator. Each metallic tip may be comprised of a circular cross-sectional stiff solid wire made of nickel-chromium alloy having a diameter of 1 to 4 millimeters, and more preferably 1.5 to 3.5 millimeters. Each metallic tip may include a bend portion that directs the end of the metallic tip towards the other metallic tip in the pair. The pair of metallic tips may be bent or otherwise separated by an air gap across which a discharge spark may be provided continuously to ignite pellets in the burn pot  242 . Preferably the air gap may be 4 to 6 millimeters, or more preferably 4.5 to 5.5 millimeters. An electrical connector, such as conductive wire, may connect the electrodes  364  to a spark generator  360  that is in electrical communication with, and powered by, the battery  372 . Preferably, the spark generator  360  may be provided in close proximity to the battery  372 . The spark generator  360  may include a booster coil and a Darlington transistor and have a power requirement of 12V/3 A to provide a continuous spark. By “continuous” spark, it is meant to describe a spark that is not a “pulse” spark that jumps the air gap quickly and lasts less than 1 second, but instead a constant arc of spark lasting greater than 1 second, and in some instances lasting constantly for up to 15-20 minutes to create combustion of solid fuel. At heater start up, the spark generator  360  preferably creates a continuous spark for about 4 minutes or more to insure combustion. 
     With reference to  FIG.  11   , the readout panel/controller  304  may be used to control the operation of the fan assembly  140 , the operation of the blowers  130 , the operation of the auger  340 , and/or the operation of the spark generator  360  to provide a selective level of pellet combustion and heat generation in the burn pot  242 . The controller  304  may use a feed-back loop including one or more of the RTDs  402  to provide a selected level of heat. The battery  372  may be of sufficient amperage and/or wattage to provide several hours of operation in terms of power for the auger  340 , the fan assembly  140 , the blowers  130 , and the spark generator  360 . 
     While the heater  10  may be powered by an alternating current (AC) power supply in some embodiments, in a preferred embodiment, the battery pack  372  powers the device. The battery pack  372  may power all onboard electrical components of the heater  10 , including without limitation, the readout panel/power supply controller  304 , the temperature sensor  402 , the fan assembly  140 , the blowers  130 , the auger motor  348 , and the spark generator  360 . The battery pack  372  and battery compartment  370  may be electrically connected via a positive battery output (12V+)  520 , a negative or ground battery output (12V−)  522 , and a battery charge connection  524  to a distribution board  526 . In turn, the distribution board  526  may be electrically connected to a main positive output (12V+)  508 , a main negative or ground output (12V−)  510 , an AC adapter negative or ground input (12V−)  512 , and an AC adapter positive input (12V+)  514 . The AC inputs  512  and  514  may be connected to an AC recharging receptacle adapted to connect to a conventional AC wall socket plug (not shown). In a preferred embodiment, the battery pack may include six (6) lithium-ion cells that provide 5 Ah/8 A output at a maximum/12V. The battery pack  372  may be of sufficient amperage and/or wattage to provide several or more hours of heater operation in terms of power for the RTD  402 , the controller  304 , the auger motor  348 , the fan assembly  140 , the blowers  130 , and the spark generator  360 . 
     As will be understood by those skilled in the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The elements described above are provided as illustrative examples for implementing the invention. One skilled in the art will recognize that many other implementations are possible without departing from the present invention as recited in the claims. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention. It is intended that the present invention cover all such modifications and variations of the invention, provided they come within the scope of the appended claims and their equivalents.