A hot water supply device (1) includes: a fin and tube type heat exchanger (17) for aplying heat to water with combustion gas; a temperature detection means (32) for detecting an exhaust temperature after heat exchange by the heat exchanger (17); and a determination means that determines that scale is deposited within the heat exchange tubing (27) of the heat exchanger (17) if the exhaust temperature detected by the temperature detection means (32) is higher than a set temperature.

It is common in heating systems, such as in a hot water heater for there to be a combustor with the exhaust gases from the combustor provided to a heat exchanger to heat up the water. Disclosed herein is an integrated heat exchanger and burner assembly in which the combustion occurs proximate the surface of the heat exchanger. Such a system may include at least one tube that is coiled into a number of turns, that is a tube coil with the at least one tube having an inlet and an outlet and the distance between adjacent turns is less than a predetermined distance, i.e. a the quench distance.

A water heater according to the present invention comprises: a combustion chamber; a burner provided to cause a combustion reaction in the combustion chamber; a plurality of circulation pipes that communicate with the combustion chamber so that combustion gas generated by the combustion reaction flows through the inside; a circulation housing that surrounds the plurality of circulation tubes and the combustion chamber so that circulating water flows to the surroundings of the plurality of circulation tubes and the combustion chamber; a pre-stage heat exchanger that communicates with the plurality of circulation tubes to exchange heat between direct water and combustion gas passing through the plurality of circulation tubes to generate pre-stage hot water; and a main heat exchanger that is connected to the pre-stage heat exchanger and the circulation housing, to generate hot water by exchanging heat between the hot water received from the pre-stage heat exchanger and the hot water delivered from the circulation housing.

A heat-exchanger unit according to the present invention comprises: a sensible-heat heat-exchange portion arranged in a sensible-heat heat-exchange area for receiving sensible heat generated by a combustion reaction and thereby heating water, the sensible-heat heat-exchange portion having a sensible-heat heat-exchange pipe for receiving the water and causing same to flow through the interior thereof, thereby forming a sensible-heat channel along which the water flows; and a latent-heat heat-exchange portion positioned downstream of the sensible-heat heat-exchange area with reference to a first reference direction along which combustion gas generated during the combustion reaction flows, the latent-heat heat-exchange portion being arranged in a latent-heat heat-exchange area for receiving latent heat generated during a phase change of the combustion gas and thereby heating the water, the latent-heat heat-exchange portion having a latent-heat heat-exchange pipe for receiving the water and causing same to flow through the interior thereof.

A fluid heating system for heating a production fluid using a thermal transfer fluid, the production fluid being contained in a vessel includes an electric blower configured to receive ambient air and electrical input power and to provide output source air, a combustion system configured to receive the source air from the electric blower and to receive fuel and to provide the thermal transfer fluid, a heat exchanger configured to receive the thermal transfer fluid from the combustion system and configured to provide heat exchange from the thermal transfer fluid to the production fluid, and to provide output exhaust gas, and wherein the electric fan provides a predetermined volume flow rate of the output source air at a predetermined blower efficiency such that the fluid heating system has a Bulk Heat Flux of at least about 14.7 kBTU/Hr/ft.sup.2 and a Pressure Drop of at least about 0.7 psi.

A heat recovery system for recovering waste heat from exhaust gases that are expelled through a flue that are generated as a byproduct from a heating system, comprises a venting arrangement that connects to the flue from the heating system and a motorized damper to direct the exhaust gases from the flue through the venting arrangement to an intake plenum. The intake plenum directs the exhaust gases to a heat exchanger that comprising a series of serpentine conduits between which the exhaust gases pass through. The heat exchanger is connected to exhaust plenum which is in turn connected to an exhaust fan that draws the exhaust gasses through the heat recovery system. The heat exchanger further comprises a series of inlet ports and outlet ports that add and remove coolant to the serpentine conduits at selected temperatures.

A condensation heat exchanger including at least one helically-coiled tube, inside which a fluid to be heated can circulate, a deflector, and a shell mounted inside which the tube, the shell having a gas-discharge sleeve having a bottom and a facade for feeding and/or producing a hot gas, inside the shell. The shell comprises a tubular metallic shroud closed at its two ends by a facade and a bottom, wherein the bottom is made of composite plastic, the rear edge of the shroud has a plurality of fastening tongues, the bottom has, at its periphery, a plurality of fastening slots arranged along at least part of its circumference, each fastening slot bordered longitudinally by a first longitudinal rib projecting outwardly, and wherein each fastening tongue is inserted into a fastening slot and folded twice around the first rib.

A heat exchanger for a boiler or similar heating device comprises a casing and a tube assembly inside the casing. The tube assembly includes a plurality of modules (6.sub.x, 6.sub.y) arranged in a juxtaposed configuration, each module (6.sub.x, 6.sub.y) having an at least approximately annular shape. The modules (6.sub.x,6.sub.y) each include a respective tube (7) that is at least partially embedded in a respective thermally conductive body (8) overmoulded to the tube (7). Each thermally conductive body (8) defines an upper face and a lower face of the respective module (6.sub.x, 6.sub.y), where at least at the upper face of a first module (6.sub.y) and the lower face of a second module (6.sub.x) the corresponding thermally conductive body (8) defines upper fins (24) and lower fins (23.sub.x), respectively, which extend in height substantially in an axial direction of the tube assembly and extend in length substantially in a radial direction of the tube assembly (5). The upper fins (24) of the thermally conductive body (8) of the first module (6.sub.y) are in an axially staggered position with respect to the lower fins (23.sub.x) of the thermally conductive body (8) of the second module (6.sub.x), with the upper fins (24), on the one hand, and with the lower fins (23.sub.x), on the other hand, which are at mutual distances such that the upper fins (24) of the thermally conductive body (8) of the first module (6.sub.y) are set between the lower fins (23.sub.x) of the thermally conductive body (8) of the second module (6.sub.x), or vice versa. In this way, between each upper fin (24) of the thermally conductive body (8) of the first module (6.sub.y) and each lower fin (23.sub.x) of the thermally conductive body (8) of the second module (6.sup.x), or vice versa, a respective radial passageway (P) is defined for the combustion fumes produced by a burner equipping the heat exchanger.