A furnace for a heating, ventilation, and air conditioning (HVAC) system includes a fuel valve configured to regulate an amount of fuel supplied to a burner of the furnace, a draft inducer blower configured to draw an air flow into the burner, and a controller configured to determine a target operating parameter value of the furnace, determine an air to fuel ratio corresponding to the target operating parameter value, and control operation of the fuel valve, the draft inducer blower, or both based on the air to fuel ratio.

This invention relates to a heater. A combustion air blower feeds combustion air to a burner device. The burner device burns a gas-air mixture from the combustion air and a fuel and serves for heating air. A circulating air blower discharges heated air from the heater. A control device acts on at least one component of the heater, wherein a night mode parameter set associated with an operation of the heater in a night mode and a default parameter set are stored in a data storage device. After an activation of the night mode, the control device accesses the night mode parameter set and uses the same for acting on the component. The night mode parameter set effects a reduction of background noise generated by the heater.

The flameless heater system includes an energy source comprising a diesel engine configured to create volumes of air, a hydraulic system to control engine loading for heat generation and for air moving, and a control system, operatively coupled with the energy source and the hydraulic system to control at least one of a speed of the diesel engine, a loading of the diesel engine, or a fan speed.

A transfer tube for a thermal transfer device can include at least one wall having an inner surface and an outer surface, where the inner surface forms a cavity, where the at least one wall further has a first end and a second end. The first end can be configured to couple to a terminus of a heat exchanger of the thermal transfer device. The second end can be configured to couple to a collector box of the thermal transfer device. At least a portion of the at least one wall can be disposed in a vestibule of the thermal transfer device. The cavity can be configured to simultaneously receive a first fluid that flows from the first end to the second end and a second fluid that flows from the second end to the first end.

A transfer tube for a thermal transfer device can include at least one wall having an inner surface and an outer surface, where the inner surface forms a cavity, where the at least one wall further has a first end and a second end. The first end can be configured to couple to a terminus of a heat exchanger of the thermal transfer device. The second end can be configured to couple to a collector box of the thermal transfer device. At least a portion of the at least one wall can be disposed in a vestibule of the thermal transfer device. The cavity can be configured to simultaneously receive a first fluid that flows from the first end to the second end and a second fluid that flows from the second end to the first end.

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 carrier device for mounting a preferably fuel-operated heater (34) on a vehicle. The carrier device includes a mounting area (20) for mounting the carrier device (14) on a vehicle and a carrying area (152) for mounting a heater (34) on the carrier device (14). A combustion air line area (52) is provided for sending combustion air to a combustion air inlet (55) of a heater (34), or/and a heat transfer medium line area (60) is provided for sending heat transfer medium flowing in a heat transfer medium circuit (176) of a vehicle through the carrier device (14) or/and to or from a heat exchanger area (38) of the vehicle heater (34).

A gas furnace includes: a burner in which a mixture of air and fuel gas burns; a heat exchanger through which a combustion gas produced by the combustion of the mixture flows; a duct including a room air duct through which air coming from a room passes and a supply air duct through which air supplied to the room passes; a blower that induces a flow of the room air supplied as the supply air to the room through the heat exchanger; and a humidification and dehumidification device with no water supply installed on one side of the supply air duct. The amount of moisture contained in the supply air is adjusted by an adsorbent coated on the surface of the humidification and dehumidification device with no water supply.

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.

A failsafe hydrocarbon-based gas (HBG) leak detection (HLD) and mitigation (HLM) system/method for use in heating, ventilation, and air conditioning (HVAC) systems that incorporates a hydrocarbon gas sensor (HGS), sensor signal conditioner (SSC), alarm status indicator (ASI), and digital control processor (DCP) is disclosed. The HGS detects ambient hydrocarbon gas (AHG) and presents a hydrocarbon sensor voltage (HSV) to the SSC. The DCP and SSC form a closed control loop (CCL) in which the SSC electrical characteristics are adjusted by the DCP such that the HSV is continuously and dynamically recalibrated to account for background HBG levels, changes in ambient air conditions, HGS manufacturing tolerances, and other field-specific operational conditions that impact the HGS detection capabilities. The DCP is configured to log alarms to the ASI if a HGS HBG leak is detected and optionally shutdown gas flow to one or more HBG target (HBT) system components.