GAS-POWERED WATER HEATER

Abstract: This gas-powered water heater is of the type comprising a water tank (1) which extends substantially vertically, a combustion chamber (2) arranged on the bottom of the tank and a gas burner (3) arranged inside the combustion chamber. In order to provide a high security against gas escape, simplicity in installation together with a simple structure, the combustion chamber (2) and the discharge duct (6,18) for the burnt gases are sealingly isolated from the room, the inflow of combustion air occurring through at least one duct (5,19) which connects the combustion chamber to the outside.

Description: The present invention relates to a gas-powered water heater. Water heaters are currently known which employ the heat produced by the combustion of a gas to produce hot water. Such water heaters substantially consist of a water tank which is outwardly thermally insulated and downwardly provided with a combustion chamber, wherein the gas burner is inserted. The combustion chamber is connected to the stack by means of one or more smoke-pipes extending in the tank of the water to be heated. Though it is in particularly widespread use, this type of gas-powered water heater is highly dangerous due to the fact that the combustion chamber is not isolated from the room wherein the apparatus is installed since the air required for combustion is indeed taken from this room. The consequsnt risks are sadly known: accidental leakage of gas from the burne; leakage of carbon oxide in case of poor draught of the stack. Moreover, in water heaters of the type described above no possibility of use for heating rooms, in particular using stored heat, is provided. Gas-powered heaters are also known comprising a combustion chamber which is isolated from the room in which the heater is installed and connected with the outside through a discharge duct for the burnt gases and an inlet duct for the combustion air. A heater of this type is disclosed in the DE-A-2 201 317 wherein a discharge duct is provided having an exhaust portion extending through the water tank according to a vertical axis. However the heater according to the DE-A-2 201 317 has a limited efficiency owing to the fact that the inflow of combustion air depends on the natural draft created by the rising burnt gases. The aim of the present invention is therefore to solve the above described problem by devising a gas-powered water heater which, besides having a particularly high thermal efficiency, is highly secure, eliminating or at least reducing the risk of gas leaks and easy to install. The aim is achieved, according to the invention, by the present gas-powered water heater, as defined in the appended claim. The details of the invention will become apparent from the detailed descrition of a preferred embodiment of a gas-powered water heater, illustrated only by way of non-limitative example in the accompanying drawing, wherein: Figure 1 is a vertical cross section view of the water heater according to the invention; Figure 2 is a top view thereof. With reference to the above figures, the water heater according to the invention comprises a cylindrical water tank 1 which extends substantially vertically. On the bottom of the tank 1 a combustion chamber 2 is arranged, inside which a gas burner 3, supplied by a conduit 4, is arranged. The air required for combustion is sent to the chamber 2 by means of a pipe 5 vertically extending within the tank 1, adjacent to a pipe 6 for discharging the burnt gases. By virtue of this arrangement, the combustion chamber 2 is sealingly separated from the room wherein the water heater is installed. Pipes 7 and 8, respectively intended for inflow and outflow of heated water, also lead into the tank 1. The tank 1 is outwardly surrounded by a jacket 9 of thermally insulating material, such as a cellular polyurethane and the like. At the top 10 of the jacket there is arranged a dome 11 which is connected to the pipe 5. An aspirator element 12 is arranged inside the dome 11 and is connected to the pipe 6 for forced ejection of the burnt gases through an exhaust pipe 13. The pipe 13 is arranged coaxially inside a further pipe 14 through which the combustion air reaches the dome 11. Thus the combustion air, before reaching the burner, is preheated by flowing in countercurrent along the burnt gas exhaust pipe 13 and subsequently releases part of this heat to the water contained in the tank by flowing in the pipe 5. Moreover, the forced draught provided by the aspirator 12 allows reduction of the fume passages and elimination of the flue, with obvious advantages as to efficiency and ease of installation. Besides the safety provided by the intake of air from the outside of the building, and besides the improved thermal efficiency offered by the use of air as means for recovering heat which would be otherwise dispersed, the present invention offers a further advantage which can be particularly appreciated during the installation of the apparatus. The advantage resides in the fact that it is possible to freely orientate the double pipe 13,14 which connects the apparatus with the outside environment, regardless of the position assumed by the water heater during mounting onto the wall. In fact, as is clear from fig. 1, the dome 11 is adapted to rest on a sealing gasket 15 and to be retained, by screw means, on the jacket top 10. The rotation of the dome 11 occurs by pivoting on the central pipe 6 and also by virtue of a suitable gasket 16 provided between this pipe and aspirator 12 which moves with the dome.

Claims: Gas-powered water heater, comprising a water tank (1) which extends substantially vertically, a combustion chamber (2) arranged on the bottom of said tank and a gas burner (3) arranged inside said combustion chamber, and wherein the combustion chamber (2) and the discharge duct (13,6) for the burnt gases, which includes an exhaust duct (6) extending through said tank according to a vertical axis, are sealingly isolated from the room in which the heater is installed, the inflow of combustion air occurring through at least one duct (5,14) which connects the combustion chamber to the outside characterized in that it further comprises a dome (11) rotatably arranged on the top of said tank (1) and connected to said combustion chamber (2) through a portion (5) of said combustion air inlet duct which extends through said tank in proximity of said exhaust pipe, suction means (12) being provided inside said dome (11) and rotatably associated to the upper end of said exhaust pipe (6), said inlet duct having a portion (14) radially extending from said dome (11), and coaxially surrounding a portion of said exhaust duct connecting said suction means (12) with the outside, said dome (11) and said suction means (12) being rotatable according to an axis coincident with the axis of said exhaust pipe (6).

Inventors: MARIANI, MARIO
Applicants: ATI DI MARIANI MARIO & C. S.N.C.
Application year: 1987
Main classification: F24H9
IPC codes: F24H1