Overflow protection and monitoring devices capable of coupling to a drainage pan and may include: a drainage line; a base, the base including an input port; a dry section; and a wet section, the input port capable of coupling to the drainage pan; a base cover, the base cover removably coupled to the base, the base cover including a base cover output port capable of coupling to the drainage line; a fluid displacement mechanism located in the wet section, the fluid displacement mechanism including a fluid displacement mechanism output port; a fluid detection mechanism located in the wet section; and a base attachment, the base attachment coupled to the fluid displacement mechanism output port and the base cover output port, the base attachment including an air relief port and back-flow preventer; a control unit capable of energizing the fluid displacement mechanism upon receiving a signal from the fluid detection mechanism.

A furnace has a primary heat exchanger tube, a secondary heat exchanger comprising a plurality of secondary heat exchanger tubes, a hot header configured to provide a fluid flow path between an output of the primary heat exchanger tube to an input of the secondary heat exchanger, and a perforated fluid flow plate disposed at least partially within the hot header.

A furnace has a primary heat exchanger tube, a secondary heat exchanger comprising a plurality of secondary heat exchanger tubes, a hot header configured to provide a fluid flow path between an output of the primary heat exchanger tube to an input of the secondary heat exchanger, and a perforated fluid flow plate disposed at least partially within the hot header.

The heat exchange device (200) includes a primary heat exchanger (10), a secondary heat exchanger (20), and a connecting pipe (60). The connecting pipe connects the primary heat exchanger and the secondary heat exchanger. The primary heat exchanger (10) includes a primary heat exchange part (11), a shell plate (12) surrounding the primary heat exchange part, and a body pipe part (13) for cooling the shell plate. The body pipe part (13) is disposed closer to a burner than the primary heat exchange part (11) and is connected to the connecting pipe (60). The primary heat exchange part (11) includes a first heat transfer tube part (111) connected to the body pipe part (13), and a second heat transfer tube part (112) connected to the first heat transfer tube part and disposed on a side opposite to the body pipe part with respect to the first heat transfer tube part.

A safe water heater comprises a housing assembly, a box assembly, and a water inlet and outlet assembly. The housing assembly comprises a first housing with a mounting cavity. The box assembly comprises a water tank with a water-containing cavity. The water inlet and outlet assembly comprises a water inlet subassembly and a water outlet subassembly. The water inlet subassembly comprises a second water inlet pipe communicating with the water-containing cavity, a first water inlet pipe able to communicate with outside, and a leak-proof mechanism. The leak-proof mechanism is capable of sealing a water inlet of the second water inlet pipe.

A structure for detecting a leak, wherein the structure is supported upon a supporting surface, the structure including a leak detector; and a bottom-facing surface comprising an inverted depression in which the leak detector is disposed, the inverted depression is configured to be suitable for inducing capillary actions in a liquid collected on the supporting surface, wherein when the inverted depression comes in contact with the liquid at its periphery, the liquid is drawn to the leak detector to be detected.

Certain exemplary embodiments can provide a system, machine, device, and/or manufacture that is configured for operably releasing condensate from a furnace combustion gas containment system without allowing a substantial quantity of drain air to enter the condensate producing system from a drain or a substantial quantity of combustion gas to flow through the system, machine, device, and/or manufacture.

A trap apparatus of condensate water according to the present invention comprises: a neutralizing part including an inlet through which condensate water is introduced, an internal space for containing a neutralizing agent for neutralizing the introduced condensate water, and a condensate water passage through which the condensate water that was neutralized by the neutralizing agent in the internal space is discharged; a discharge part including a storage space for storing the condensate water which is directly or indirectly introduced through the condensate water passage, an outlet which is open in a circular shape so as to discharge the stored condensate water, and a spherical ball capable of closing the outlet by being seated on the outlet, wherein the ball is spaced from the outlet by buoyancy of the condensate water when the condensate water is contained in the storage space above a critical water level, such that the condensate water can be discharged through the outlet, and the condensate water can be neutralized simultaneously with discharging of only the condensate water without exhaust gas.

A trap apparatus of condensate water according to the present invention comprises: a neutralizing part including an inlet through which condensate water is introduced, an internal space for containing a neutralizing agent for neutralizing the introduced condensate water, and a condensate water passage through which the condensate water that was neutralized by the neutralizing agent in the internal space is discharged; a discharge part including a storage space for storing the condensate water which is directly or indirectly introduced through the condensate water passage, an outlet which is open in a circular shape so as to discharge the stored condensate water, and a spherical ball capable of closing the outlet by being seated on the outlet, wherein the ball is spaced from the outlet by buoyancy of the condensate water when the condensate water is contained in the storage space above a critical water level, such that the condensate water can be discharged through the outlet, and the condensate water can be neutralized simultaneously with discharging of only the condensate water without exhaust gas.

An oil boiler includes an outer container having openings at opposite ends, a combustion chamber that covers an opening at an upper end of the outer container and in which a combustion reaction occurs, a lower cover that covers an opening at a lower end of the outer container, a plurality of flue tubes to heat heating water flowing in the outer container by guiding combustion gas, a burner including a fuel nozzle that sprays fuel, an air nozzle that injects air, and a spark plug that ignites a mixture of the fuel and the air, and a flame tube part that defines a tube space by surrounding a partial space in which the mixture is ignited, the flame tube part including a flame tube having an open lower end and a recirculation hole formed through the flame tube such that the combustion gas is introduced into the flame tube.