Abstract: 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.

Abstract: 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.

Abstract: A furnace may include a furnace cabinet, an inducer blower, and a flue vent adapter. The furnace is configured as a multi-poise furnace and configured to be installed and operated in each of the horizontal left flow orientation, the horizontal right flow orientation, the upflow orientation, and the downflow orientation. The flue vent adapter is used when the furnace is installed and operated in the downflow orientation. Alternatively, the flue vent adapter is used when the furnace is installed and operated in each of the horizontal left flow orientation and the horizontal right flow orientation. The flue vent adapter has a unitary construction to reduce manufacturing costs, reduce a pressure drop through the flue vent adapter, and reduce leakage.

Abstract: A furnace may include a furnace cabinet, an inducer blower, and a flue vent adapter. The furnace is configured as a multi-poise furnace and configured to be installed and operated in each of the horizontal left flow orientation, the horizontal right flow orientation, the upflow orientation, and the downflow orientation. The flue vent adapter is used when the furnace is installed and operated in the downflow orientation. Alternatively, the flue vent adapter is used when the furnace is installed and operated in each of the horizontal left flow orientation and the horizontal right flow orientation. The flue vent adapter has a unitary construction to reduce manufacturing costs, reduce a pressure drop through the flue vent adapter, and reduce leakage.