DE8911393U1 - Gas fired water heater - Google Patents

Description

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Description: Gas-fired hot water heater

Description:

The innovation relates to a gas-fired, encapsulated storage water heater with balanced through-flow and natural draft.

The innovation relates in particular to a hot water heater of this type which is simpler both in construction and in operation, and which is also more reliable and more convenient in use than currently available hot water heaters of the same class.

In the gas fired sealed or encapsulated storage water heaters currently in existence, the combustion equipment is sealed or encapsulated from the environment in which the water heaters themselves are located, and they have an increased draft from an electric fan which draws air from outside and then discharges exhaust gases to the outside.

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This mode of operation requires the hot water heater to be supplied with electrical energy.

In addition, an electric fan, an air monostat required by law for safety reasons and a control device to control or regulate all operations are required.

Such an electronic control device controls or regulates in particular the power supply to the fan following the request for hot water from a thermostat, as well as the operation of the safety monostat which releases the air flow, the usually electronic opening of the gas valve to ignite the hot water heater, the sensing of the flame by an ionization electrode and the closing of the gas valve if no flame is detected within a predetermined time.

The operation of hot water heaters of this type is complicated and involves very considerable construction costs, so that designs of this type are only advantageous for certain sizes and applications, while this is less advantageous for simpler or "more economical" designs of storage water heaters. 25

One of the main problems with gas fired storage water heaters of the type described is that due to the presence of a fan in the flow path it is impossible to maintain the pilot flame so that the burner must be repeatedly re-ignited when necessary.

This means that the gas-fired water heaters of the type described currently available have the disadvantages of being expensive, consuming electrical power and being complicated to operate, making them unreliable.

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The task is therefore to create a gas-fired hot water heater which avoids the disadvantages described, which can therefore be manufactured at low cost, which is completely sealed or encapsulated and which does not require an electrical power supply.

This is achieved according to the innovation by a gas-fired hot water heater which is completely sealed or encapsulated and which has a natural draught in that pipes are arranged outside the boiler in the space between the boiler and the outer casing, which connect the upper space of the hot water heater which receives the outside air with the lower space adjacent to the burner, and in that there is a draught pipe which consists of two coaxial pipes, of which the outer pipe is connected to the upper space, while the inner pipe is connected to the exhaust pipe which runs through the boiler and is fed by the burner.

This creates a seal or enclosure, where the combustion air is supplied and the exhaust gases are simultaneously removed - without the need for a fan.

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The subject matter of the invention is therefore in particular a gas-heated storage hot water heater with a boiler, an exhaust pipe inside the boiler, a gas valve burner arrangement below the exhaust pipe, an outer casing forming an upper space at the upper part of the boiler and a lower space in the area of the gas valve burner arrangement, and an insulating packing between the outer wall of the boiler and the inner wall of the casing.

According to the innovation, it is provided that at least one air passageway is provided within the insulating packing between the inner wall of the shell and the outer wall of the boiler.

is present and the air passageway connects the upper space with the lower space, and that above the upper space and at the outlet of the exhaust pipe a coaxial pipe is arranged, through the outer pipe of which the combustion air enters, while the exhaust gases exit from the inner pipe connected to the exhaust pipe, whereby all parts of the hot water heater are reliably sealed or encapsulated.

The air passageways in the packing between the shell and the boiler preferably consist of several tubes, the dimensions and number of which can be selected to suit the heat transfer and the performance of the burner.

The upper and lower spaces are preferably sealed by lids or covers arranged on the casing.

The valve of the gas valve burner arrangement is preferably a thermostatic expansion valve of conventional design. 20

A preferred embodiment of the innovation is described below with reference to the drawing, which schematically shows a section through the gas-fired hot water heater according to the innovation. The embodiment shown and described is merely an example and is not restrictive.

The gas-fired storage water heater shown in the drawing contains a boiler 1 in which an exhaust pipe 2 is located.

Below the exhaust pipe 2 there is a burner arrangement 3.

The boiler 1 is arranged in an outer housing 4, which forms a jacket 5 in which the heat-insulating material is packed, preferably polyurethane foam.

Pipes 6, which connect an upper chamber 7 with a lower chamber 8 of the hot water heater, are embedded in the polyurethane foam.

The chambers 7 and 8 have lids or covers 9 and 10 with suitable dimensions and made of suitable materials so that a tight seal is achieved.

The cover 9 is connected at the top to a coaxial pipe 11, the inner part 12 of which is connected to the exhaust pipe 2.

The pilot flame is activated as in gas fired water heaters of conventional design and supplies the burner assembly 3 under direct control of a !5 fluid expansion assembly.

The flame creates a natural flow so that the combustion air enters from outside (arrows 13), flows through pipe 11 and reaches the upper chamber 7. 20

From there, the air flows through the pipes 6, it reaches the lower chamber 8 and then to the burner arrangement 3.

Exhaust gases, which have given off their heat to water in the boiler 1 through the walls of the exhaust pipe 2, are discharged in the direction of the arrows 14 through pipe 12.

When the burner assembly 3 is out of operation, the pilot flame can produce a weak flow sufficient to maintain the flame.

The dimensions of the air flow paths and in particular of the coaxial pipes 11 and 12 of the upper and lower chambers 7 and 8, respectively, and of the pipes 6, must be determined depending on the heat transferred by the burner arrangement and the output of the hot water heater.

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The innovation creates a gas-fired, sealed or encapsulated storage water heater, which offers the advantage that disruptions to the combustion process do not pose a risk to the user.

In addition, the very simple design and operation offers the advantage that the hot water heater produced in this way is very reliable and practical in use.

Also, a gas-fired, sealed, natural flow storage hot water heater is created, the manufacturing costs of which are significantly lower than those of the hot water heaters currently on the market, and this is a significant advantage of the hot water heater according to the innovation, as it is relevant to the type of users intended.

Finally, the arrangement of two coaxial tubes to form the natural flow leads to significantly lower thermal losses in the steady state compared to the current types, since the coaxial tube causes lower pressure losses than is the case with conventional draft tubes.

A convenient application or modification of the design is the possibility of creating a kit of additional devices, such as the upper and lower chambers, the coaxial exhaust pipe and pipes for the supply of combustion air; this can be arranged outside the shell of the water heater and such a kit can also be used to equip previously non-sealed or encapsulated water heaters in order to convert them into the sealed or encapsulated state.

The innovation has been described with specific reference to preferred embodiments, but it should be noted that modifications and/or alterations can be made within the scope of expert action without detracting from the invention.

the spirit and scope of protection of the innovation with the claimed priority.

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Claims (5)

Expectations: 1. Gas-fired storage water heater with a boiler, an exhaust pipe within the boiler, a gas valve burner arrangement below the exhaust pipe, an upper space at the upper part of the boiler and a lower space in the area of the gas valve burner arrangement in the outer shell, and an insulating packing between the outer wall of the boiler and the inner wall of the shell, whereby q eks η η ;-; e ~ ... that at least one air passageway is present within the insulating packing between the inner wall of the shell and the outer wall of the boiler and the air passageway connects the upper space with the lower space, and that !5 above the upper space and at the outlet of the exhaust pipe a coaxial pipe is arranged, through the outer pipe of which the combustion air enters, while the exhaust gases exit from the inner pipe connected to the exhaust pipe, whereby all parts of the hot water heater are reliably sealed or encapsulated. 2. Gas-fired hot water heater according to claim 1, characterized in that a tube bundle is arranged between the inner wall of the shell and the outer wall of the boiler within the insulating packing. 3. Gas-fired water heater according to claim 1 or 2, characterized in that the upper and lower spaces are sealed by lids or covers arranged on the casing. 4. Gas-fired hot water heater according to one of claims 1 to 3, characterized in that the valve of the gas valve burner is a thermostatic expansion valve. 5. Gas-fired storage water heater according to one of claims 1 to 4, characterized in that it consists of a gas-fired hot water heater of conventional design and additionally a coaxial exhaust pipe, pipe outside the casing for introducing air and upper and lower spaces, such that a sealed or encapsulated hot water heater with natural draught is formed, 1-fcs