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.

The combustion device includes: a burner; an igniter; a fuel supply unit that supplies fuel to the burner; a blower fan that supplies air for combustion; an exhaust port that discharges combustion exhaust; a device control unit that, before ignition of fuel supplied to the burner by operation of the igniter, performs air purge of the burner at a predetermined air blowing amount by driving the blower fan; and a setting means that is set when a check valve for preventing back flow of exhaust is connected to the exhaust port. When the setting means is set to indicate that the check valve is connected, the device control unit controls the operation of the blower fan so that slow-start air purge is performed in which the time interval from the start of air purge until the predetermined air blowing amount is reached becomes longer, than in the case in which no such check valve is connected.

The combustion device includes: a burner; an igniter; a fuel supply unit that supplies fuel to the burner; a blower fan that supplies air for combustion; an exhaust port that discharges combustion exhaust; a device control unit that, before ignition of fuel supplied to the burner by operation of the igniter, performs air purge of the burner at a predetermined air blowing amount by driving the blower fan; and a setting means that is set when a check valve for preventing back flow of exhaust is connected to the exhaust port. When the setting means is set to indicate that the check valve is connected, the device control unit controls the operation of the blower fan so that slow-start air purge is performed in which the time interval from the start of air purge until the predetermined air blowing amount is reached becomes longer, than in the case in which no such check valve is connected.

The present disclosure relates to an adjustable collar for inserting a pipe therein, in particular for positioning and securing a pipe to an apparatus. The present disclosure provides an adjustable collar for inserting a pipe therein, which accepts pipes of any diameter within a predetermined range instead of only accepting pipes of certain standard diameters. Furthermore, pipes can be secured into the adjustable collar without the need for hand tools, adapters, or other accessories.

An exhaust structure for combustion apparatus includes an exhaust tube connected to a water heater, an exhaust pipe through which the exhaust tube is introduced, and an exhaust tube fixing member for fixing a position of the exhaust tube relative to the exhaust pipe. The exhaust tube fixing member includes a first fixing portion having a cylindrical shape and fixed to the exhaust tube, and an attaching portion connected to the first fixing portion and attached to the exhaust pipe. The attaching portion have a first cylindrical portion having a first inner diameter D2, and a second cylindrical portion having a second inner diameter D3 smaller than the first inner diameter D2 of the first cylindrical portion.

An exhaust structure for combustion apparatus includes an exhaust tube connected to a water heater, an exhaust pipe through which the exhaust tube is introduced, and an exhaust tube fixing member for fixing a position of the exhaust tube relative to the exhaust pipe. The exhaust tube fixing member includes a first fixing portion having a cylindrical shape and fixed to the exhaust tube, and an attaching portion connected to the first fixing portion and attached to the exhaust pipe. The attaching portion have a first cylindrical portion having a first inner diameter D2, and a second cylindrical portion having a second inner diameter D3 smaller than the first inner diameter D2 of the first cylindrical portion.

A reverse combustion type combustion apparatus (1) includes a combustion section (2) that combusts fuel in a downward direction, heat exchangers (4, 5) disposed under the combustion section (2), and an exhaust box (6) disposed under the heat exchangers (4, 5). The exhaust box (6) is a molded product made from a synthetic resin material; the exhaust box (6) includes an opening portion (30) for introduction of combustion exhaust gases generated by an upper portion, a fixing portion (33) for fixing the heat exchanger (5), and an inclined bottom portion (35) that collects condensed water generated by the heat exchanger (5); and, at the lower end portion of the exhaust box (6), at least three legs (40) are integrally formed and make the exhaust box (6) stand up by itself.

A reverse combustion type combustion apparatus (1) includes a combustion section (2) that combusts fuel in a downward direction, heat exchangers (4, 5) disposed under the combustion section (2), and an exhaust box (6) disposed under the heat exchangers (4, 5). The exhaust box (6) is a molded product made from a synthetic resin material; the exhaust box (6) includes an opening portion (30) for introduction of combustion exhaust gases generated by an upper portion, a fixing portion (33) for fixing the heat exchanger (5), and an inclined bottom portion (35) that collects condensed water generated by the heat exchanger (5); and, at the lower end portion of the exhaust box (6), at least three legs (40) are integrally formed and make the exhaust box (6) stand up by itself.

In an air supply and exhaust adapter for a combustion device of a forced air supply and exhaust type, with the combustion device comprising an air supply section and an exhaust section being provided to project from a top plate portion of an outer casing; comprising a base portion that comprises a box shaped configuration and an open bottom portion, an air supply intake portion that is formed on the top surface portion of the base portion so as to cover the air supply section and to take in air from the surroundings of the combustion device, a circumferential wall portion that surrounds the periphery of the exhaust section; and a communication passage defined between the top surface portion and the top plate portion so as to communicate the space between the exhaust section and the circumferential wall portion with the air supply intake portion; the communication passage being constructed so that, due to the operation of the air blower means, the gauge pressure therein becomes negative.

In an air supply and exhaust adapter for a combustion device of a forced air supply and exhaust type, with the combustion device comprising an air supply section and an exhaust section being provided to project from a top plate portion of an outer casing; comprising a base portion that comprises a box shaped configuration and an open bottom portion, an air supply intake portion that is formed on the top surface portion of the base portion so as to cover the air supply section and to take in air from the surroundings of the combustion device, a circumferential wall portion that surrounds the periphery of the exhaust section; and a communication passage defined between the top surface portion and the top plate portion so as to communicate the space between the exhaust section and the circumferential wall portion with the air supply intake portion; the communication passage being constructed so that, due to the operation of the air blower means, the gauge pressure therein becomes negative.