Abstract: A heating, ventilation, and/or air conditioning (HVAC) system including a baffle disposed vertically adjacent to a heat exchanger, and a method for controlling the flow of a refrigerant leak are provided. The baffle may direct at least a portion of a refrigerant leak toward a refrigerant detection assembly. The refrigerant detection assembly may include a nondispersive infrared (NDIR) sensor. The baffle may include a fishbone configuration or a helical configuration. The baffle may direct substantially all of the refrigerant leak away from a control box, which may include at least one potential ignition source (e.g., an electrical component, such as a contactor). When the heating, ventilation, and/or air conditioning (HVAC) system utilizes a flammable refrigerant, the baffle may help mitigate potential ignition of the flammable refrigerant.

Abstract: A heat pump water heater has a tank, a burner in communication with a fuel source, a flue, and a heat pump system. The heat pump system has a refrigerant path, at least a portion of which forms an evaporator in thermal communication with the flue. Another portion of the refrigerant path is in thermal communication with the water tank volume so that heat transfers from the refrigerant to the water tank volume.

Abstract: A heat exchanger comprising a shell having a first end and a second end, a first end plate and a second end plate defining a first volume with the shell that receives a first fluid therein, and at least one heat exchanger tube having a first end affixed to the first end plate and a second end affixed to the second end plate. The at least one heat exchanger tube extends through the second volume and including a cross-section defined by a plurality of lobes extending radially outwardly from the longitudinal center axis thereof. A first fluid passes through the first volume of the shell and a second fluid comprising a hot combustion gas passes through the at least one heat exchanger tube. The cross-section is constant along an entire length of the at least one heat exchanger tube.

Abstract: A heat pump water heater has a tank, a burner in communication with a fuel source, a flue, and a heat pump system. The heat pump system has a refrigerant path, at least a portion of which forms an evaporator in thermal communication with the flue. Another portion of the refrigerant path is in thermal communication with the water tank volume so that heat transfers from the refrigerant to the water tank volume.

Abstract: A composite structure provides high thermal conductivity as a thermal interface structure with a relatively low filler loading. The composite structure is formed by dispersing nanoparticles in a matrix at a low filler loading, and controlled sintering of the composite structure to induce agglomeration of the nanoparticles into a connected percolating thermally conducting network structure within the matrix.

Abstract: A composite structure provides high thermal conductivity as a thermal interface structure with a relatively low filler loading. The composite structure is formed by dispersing nanoparticles in a matrix at a low filler loading, and controlled sintering of the composite structure to induce agglomeration of the nanoparticles into a connected percolating thermally conducting network structure within the matrix.

Abstract: A composite structure provides high thermal conductivity as a thermal interface structure with a relatively low filler loading. The composite structure is formed by dispersing nanoparticles in a matrix at a low filler loading, and controlled sintering of the composite structure to induce agglomeration of the nanoparticles into a connected percolating thermally conducting network structure within the matrix.

Abstract: A composite structure provides high thermal conductivity as a thermal interface structure with a relatively low filler loading. The composite structure is formed by dispersing nanoparticles in a matrix at a low filler loading, and controlled sintering of the composite structure to induce agglomeration of the nanoparticles into a connected percolating thermally conducting network structure within the matrix.