A gas furnace is provided. The gas furnace includes a combustion part in which a fuel gas is burnt to generate a combustion gas, a heat exchanger having a gas flow path through which the combustion gas flows, a blower configured to blow air around the heat exchanger, and an inducer configured to discharge the combustion gas from the heat exchanger. The heat exchanger includes at least one single path in which a single gas flow path is formed a single-multiple return bend configured to communicate with the single path and convert a flow direction of the combustion gas, and at least one multiple path having a plurality of paths that communicate with the single-multiple return bend and form multiple gas flow paths.

A method of controlling a gas furnace system includes controlling a motor of a draft inducer to increase a speed of the motor in response to a call for heat, receiving pressure signals output by a pressure transducer, receiving signals indicating whether a pressure switch is in a first state or a second state, and determining a first status of the pressure transducer as reliable, unreliable, or questionable at a first time based on the received pressure signals from the pressure transducer, the signals indicating whether the pressure switch is in the first state or the second state, and a first status of the motor of the draft inducer at the first time. Operation of the motor of the draft inducer is stopped when the first status of the pressure transducer indicates that the pressure transducer is unreliable.

A furnace for a heating, ventilation, and air conditioning (HVAC) unit includes a heat exchange tube configured to flow combustion products therethrough and place the combustion products in a heat exchange relationship with an air flow directed across the heat exchange tube. The furnace also includes a burner assembly fluidly coupled to a first port of the heat exchange tube and configured to generate the combustion products directed into the heat exchange tube via the first port, and a draft inducer blower fluidly coupled to a second port of the heat exchange tube and configured to draw the combustion products through the heat exchange tube. The burner assembly is higher in position than the draft inducer blower relative to a base of the HVAC unit.

Disclosed are a gas furnace and an air conditioner having the same. The gas furnace includes: a burner for burning fuel; a heat exchanger extending long and providing a passage for combustion gas generated by the burner; a blower for causing a flow of air passing around the heat exchanger; and a plurality of guides passing through the heat exchanger and spaced apart from each other in a longitudinal direction of the heat exchanger. The heat exchanger includes: a first tube forming an entry of the heat exchanger; a second tube forming an exit of the heat exchanger and spaced apart from the first tube in a direction crossing the longitudinal direction of the heat exchanger; and a bend connecting the first tube and the second tube. The plurality of guides is alternately disposed in a direction in which the first tube and the second tube are spaced apart from each other.

Disclosed are a gas furnace and an air conditioner having the same. The gas furnace includes: a burner for burning fuel; a manifold providing the fuel to an entry of the burner; a heat exchanger spaced apart from an exit of the burner and providing a passage for combustion gas generated by the burner; an inducer for causing a fluid to flow through the burner and the heat exchanger; a blower for causing a flow of air passing around the heat exchanger; and an air shutter positioned between the manifold and the entry of the burner. The air shutter includes: a housing having an inner space that communicates with the manifold and the entry of the burner; and a primary hole formed to penetrate the housing and able to be opened and closed.

Disclosed are a gas furnace and an air conditioner having the same. The gas furnace includes: a fuel valve; a manifold providing a passage of fuel passing through the fuel valve; a plurality of burners provided to burn fuel provided from the manifold and spaced apart from each other in one direction; a plurality of heat exchangers providing a passage of combustion gas generated by the plurality of burners; and a blower for causing a flow of air passing around the heat exchanger. The manifold includes: a first tube having one end connected to the fuel valve and forming a first passage; a second tube extending in the one direction, forming a second passage, and facing at least one of the plurality of burners; a third tube extending in the one direction, forming a third passage, and facing remaining burners of the plurality of burners; and a three-way valve connected to the first tube, the second tube, and the third tube.

A heating apparatus, in particular for recreational vehicles like campers or caravans, comprises a heating unit and two separate heat exchanging units, which are coupled to the heating unit in parallel with each other. The heating unit comprises one burner for each heat exchanging unit, and at least one combustion air fan unit configured to supply the burners with combustion air. The burners are configured to burn fuel gas or liquid further supplied to each of the burners together with the combustion air received from the combustion air fan unit to get hot exhaust gasses. The heat exchanging units and are configured to receive the exhaust gasses from the burners, and to transfer heat from the exhaust gasses to fluids to be heated, provided within the heat exchanging units. The heat exchanging units are positioned in parallel with each other side by side on one side of the heating unit. Furthermore, the present invention refers to a recreational vehicle with such a heating apparatus.

In a combustion apparatus that includes a heat exchanger which is disposed in a combustion box, on a premise that a direction from a burner to the heat exchanger is defined as a Z-axis plus direction, a direction opposite to the Z-axis plus direction is defined as a Z-axis minus direction, and an orthogonal direction to a Z-axis direction, which is along fins of the heat exchanger is defined as a X-axis direction, a thermal insulation material is arranged on an inner surface of a swelling part that is formed at a side plate part of a combustion box and outwardly swells in the X-axis direction so as to be sandwiched from both sides in the Z-axis direction by a step that is outwardly bent in the X-axis direction, which is positioned an end, in the Z-axis plus direction, of the swelling part and a structural member of a burner, which inwardly protrudes in the X-axis direction from an end, in the Z-axis minus direction, of the side plate part. A vicinity portion of an end, in the Z-axis plus direction, of the thermal insulation material is held from an inside in the X-axis direction by a side edge portion, on each side in the X-axis direction, of the fins.

A gas turbulator is inserted in a tube of a heat exchanger to increase turbulence of gases passing through the tubes of the heat exchanger. The turbulator consists of a longitudinal metal strip running the length of the heat exchanger tube. Longitudinal tabs are punched from the interior of the metal strip. The tabs protrude in opposite directions from the plane of the longitudinal strip to form a series of slanted flip up tabs and flip down tabs in a side elevation view of the turbulator.

A heating system including at least one louver coupled with the housing of a heater including a blade and end caps on the blade for holding each louver in a fixed position during operation of the heater assembly, but also releasing the louver for adjustment in positioning relative to the axis of rotation of the louver to change air flow direction or other characteristics as desired.