Example embodiments of the present disclosure relate to improved HVAC devices and kits for HVAC devices that improve the sound attenuation associated with the device, particularly low-frequency noise. An example embodiment includes an improved furnace including a housing with a combustion air chamber, a heat exchanger chamber, and a circulation blower chamber, wherein the combustion air chamber comprises a burner assembly and a combustion air fan, the furnace also includes a sound attenuation layer including a first acoustic metamaterial layer coupled to the combustion air chamber and tuned to attenuate sound for a first frequency band, one or more housing openings fluidly connecting the combustion air chamber to an environment outside the housing, wherein the sound attenuation layer includes a discontinuous section that aligns with one or more of the housing openings.

A firebox is provided for use in a gas fireplace, the firebox comprising: a back which includes at least one combustion fan aperture, an upper end and a lower end and a length therebetween, a pair of sides, each side including an upper end, a lower end, a first riser which has an inner section and an outer section, the inner section attached to the back, a first flange, which is parallel to the back and extends outward from the back, and a second riser, wherein the outer section of the first riser, the first flange and the second riser extend above the upper end of the back and below the lower end of the back; a top which is attached to the inner section of the first risers and to the back at the upper end; and a base which is attached to the inner section of the first risers and to the back above the combustion fan aperture, to define an opening. The fireplace is also provided.

The present invention provides for a mobile heating apparatus for heating an enclosed space to a temperature sufficient to kill bed bugs. The mobile heating apparatus has a recirculation chamber having a fresh air inlet configured to receive fresh air from a fresh air area and a recirculation air inlet configured to receive recirculation air from a heated air area. The fresh air area is located outside of the area to be heated. The heated air area is located within the area to be heated. The apparatus also has an air mixture/circulation apparatus configured to mix the fresh air and the recirculation air and an air heating chamber having a heat exchanger. A mixed air inlet is in communication with the air mixture/circulation apparatus. A heated air outlet is configured to route the heated air into the heated air area. A heating apparatus is configured to provide heated combustion flow to the heat exchanger. The present invention also provides for a related method.

A device (1) for disinfecting air by combustion has a primary inlet (10) that sucks primary air into a combustion chamber (11) with a burner nozzle (12). The primary air flows along a flow path into a mixing chamber (13) arranged along the flow path after the combustion chamber (11). The primary air (L1) is heated to a first temperature. The mixing chamber (13) has an outlet (14) and at least one secondary inlet (15). Secondary air can be sucked (L2) into the mixing chamber (13) through the inlet (15). The mixing chamber (13) produces a mixed air (L3) of a third temperature of at least 100° C. from a mixing of the primary air (L1) and the secondary air (L2). The mixed air (L3) is held in the mixing chamber (13) for a predetermined residence time, and discharges the mixed air (L3) along the flow path through the outlet (14).

An air conditioning system has: an indoor fan that sends air into a room through an air-blowing flow path; a heat pump unit that air-conditions the room with a vapor compression refrigerant circuit; and a separate heat source unit that air-conditions the room with a furnace that heats air by burning fuel or an electric heater that heats air with heat generated by energization. As a refrigerant, a flammable refrigerant is sealed in the refrigerant circuit. A controller controls an operation of the indoor fan, the heat pump unit, and the separate heat source unit. When starting air conditioning in the room with the separate heat source unit, the controller brings a state where the indoor fan is in operation before causing an operation for burning fuel in the furnace.

A burner assembly includes a burner box that defines an enclosure that has a burner plate opening. A mixing tube is in fluid communication with the burner box through a mixing tube opening that extends through the burner box. A baffle creates an enclosure that at least partially separates the mixing tube opening from the burner plate opening.

A burner for use with an igniter for firing a flame into a heat-exchanger includes a body having a sidewall that defines an interior chamber. A first opening in the body receives a pre-mixed mixture of air and fuel. A second opening in the body is in fluid communication with the first opening. A distributor is connected to the body and closes the second opening. The distributor includes a first portion and at least one curved second portion provided on the first portion. Each second portion includes a plurality of first perforations in fluid communication with the first opening in the body. The first perforations of one second portion are positioned adjacent to the igniter such that ignition of the pre-mix mixture flowing through the first perforations results in a flame through the second portion. A flange extends around the first portion and includes second perforations.

A vehicle heater housing (46) has an inlet area (49), an outlet area (51) and an air flow space (47) for air to be heated with a burner chamber assembly unit (30), to be fed with combustion air and fuel. A heat exchanger area (11), including a heat exchanger housing (12), is elongated in the direction of a housing longitudinal axis (L) with an outer side (24) around which air flowing in the air flow space flows. Heat transfer ribs are on a side of the heat exchanger housing. The heater housing has a housing circumferential wall (56) and an outlet front wall area (58). The heat transfer ribs have a longitudinal edge (64) extending along the housing circumferential wall and a radial edge extending along the outlet front wall area. A distance of the radial edge from the outlet front wall area changes from radially outwards to radially inwards.

The invention relates to a portable heating system that in a first instance provides heat and in a second instance provides a source of electrical current from thermo electric modules where the produced electrical energy is intended to be forwarded to a rechargeable battery. The rechargeable battery serves as a current source for the portable heating system e.g. for driving the fuel pump and air fans. When the rechargeable battery is replenished with electrical energy a control is configured to switch the by the thermo electrical modules generated electrical energy to selected power consumers arranged with the portable heating system in order to facilitate the thermo electrical modules to keep the intended quality serving as a heat pump for transferring the produced heat from a burner to a transportation media for releasing the heat in the designated intended area.

Example embodiments of the present disclosure relate to improved HVAC devices and kits for HVAC devices that improve the sound attenuation associated with the device, particularly low-frequency noise. An example embodiment includes an improved furnace including a housing with a combustion air chamber, a heat exchanger chamber, and a circulation blower chamber, wherein the combustion air chamber comprises a burner assembly and a combustion air fan, the furnace also includes a sound attenuation layer including a first acoustic metamaterial layer coupled to the combustion air chamber and tuned to attenuate sound for a first frequency band, one or more housing openings fluidly connecting the combustion air chamber to an environment outside the housing, wherein the sound attenuation layer includes a discontinuous section that aligns with one or more of the housing openings.