JPS591946A - Heat exchanger - Google Patents

Abstract

PURPOSE:To form a hot-water supplier equipped with an additional heating facility by each set of a heat exchanger and a burner by a method wherein water in the upper part of a water reserving tank is supplied forcibly to the water introducing port of an additional heat exchanging section provided in the heat exchanger. CONSTITUTION:When hot-water is to be supplied and the burner 12 is operated under stopping a pump 24, water in the heat exchanger 14 is heated, and when the temperature of water in an upper header 17 has arrived at a value higher than a predetermined value, a temperature regulating valve 19 is opened and the hot-water is reserved in a hot-water reserving tank 11. On the other hand, when the pump 24 is operated, the water, heated by the additional heat exchanging section 20, is discharged to the lower part of the water reserving tank 23 and rises in the water reserving tank 23 mixing the inside thereof. The temperature of the water, flowing through the heat exchanger 14, is reduced, therefore, the temperature regulating valve 19 is closed and the heat of combustion gas is utilized for the additional heating only. According to this constitution, a temperature difference between the temperatures of the upper and lower parts of the water reserving tank 23 may be decreased and a heat dissipation loss through the additional heat exchanging section may be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat exchanger used in a water heater with additional heating.

As shown in FIG. 1, a conventional water heater with additional heating has a heat exchanger 1 in which a water inlet and a water outlet communicate with each other in a hot water storage tank (not shown), and water which communicates with the lower part of a water storage tank 2 for baths, etc. Two heat exchangers, a heat exchanger 3 for additional cooking, which is equipped with an inlet and a water outlet communicating with the upper part, are provided, and two heat exchangers that provide heat to each of the individual heat exchangers 1 and 3 are provided. Burners 4 and 5 are provided.

These burners 4 and 5 are each controlled and operated separately, but two heat exchangers 1 are used for hot water supply and additional heating.
, 3 and two burners 4 and 5, the entire device becomes larger and costs increase, and additional heating is performed by natural circulation, and high-temperature water is supplied to the upper part of the water storage tank 2. Therefore, the temperature difference between the upper and lower parts of the water storage tank 2 was large, which was not desirable in a bath. In addition, when the burner 5 is stopped, high-temperature water in the upper part of the water storage tank 2 flows back to the heat exchanger 3 side due to natural heat radiation through the heat exchanger 3, so the heat radiation loss in the 3 parts of the heat exchanger is extremely large. There was also an inconvenience.

The present invention has been made in view of the above-mentioned points, and is provided in a heat exchange section for exchanging heat between gas and water, located above the water, and at the same time, the water in the upper part of the water storage tank is By forcibly supplying water to the water inlet of the additional heat exchange section, the above-mentioned conventional disadvantages can be solved.

Embodiments of the present invention will be described below with reference to FIG.

In the figure, 11 is a hot water storage tank, 12 is a hot water storage tank 11
13 is a combustion tube that guides the combustion gas from the burner 12; 14 is a heat exchange section equipped with fins 14& that vertically penetrate inside the combustion tube 13; 15 is a heat exchange section 14; The lower header communicates with the hot water storage tank 11 via a water introduction pipe 16. 1T is an upper header communicating with the upper end of the heat exchange section 14, and is connected to the hot water storage tank 11 via a hot water supply pipe 18. 19 is a temperature control valve installed in the hot water supply pipe 18;
When the temperature of the water in the upper header 11 reaches a predetermined value or higher, the valve opens. The 20Fi lower header 15, the heat exchange part 14, and the upper header 11 are penetrated in the vertical direction, and the heat exchange part 14
In the additional heat exchange section that contacts the inner wall surface on the upstream side of the combustion gas,
Heat is exchanged with the water flowing inside the heat exchange section 14 and the water in the upper header 17. Reference numeral 21 denotes a reheating pipe that communicates the water inlet provided at the lower end of the additional heat exchange section 20 with the upper part of the water storage tank 23, which will be described later, and 22 indicates a water outlet provided at the upper end of the additional heat exchange section 20. 23 is a water storage tank such as a bathtub, which is installed at a height such that the upper limit of the water level B is lower than the lower header 15. Reference numeral 24 denotes a pump for forced circulation of water, which is installed in the reheating pipe 21.

In this configuration, when hot water is to be supplied, that is, when it is desired to store high-temperature water in the hot water storage tank 11, the pump 24 is stopped and the burner 12 is activated. The combustion gas from the burner 12 heats the water inside through the heat exchanger 14, and the upper header 17
Convection occurs through a circulation pipe (not shown) connecting the lower header 15 and the upper header 17, and high-temperature water begins to be stored in the upper header 17. When the water temperature in the upper header 1T reaches a predetermined value or higher, the temperature control valve 19 opens and the hot water tank 1
Hot water is stored in 1. When the temperature inside the hot water storage tank 11 reaches the set temperature, the burner 12 is stopped via a temperature detection element (not shown), and the temperature inside the hot water storage tank 11 is maintained at the set temperature.

On the other hand, when it is desired to reheat the water in the water storage tank 23 , when the pump 24 is operated, water flows into the additional heat exchange section 20 and receives heat from the water flowing through the heat exchange section 23 . It is discharged to the lower part of the water storage tank 23 through the water storage tank 23, and rises while stirring inside the water storage tank 23 due to the difference in density. On the other hand, the water flowing through the heat exchanger 14 loses its heat to the additional heat exchanger 20f: the flowing books, so the temperature decreases, so the temperature control valve 19 closes, and the heat of the combustion gas is used for additional heating. will be used only.

Next, when the additional cooking operation is completed, the burner 12 and the pump 24 are stopped, and the water accumulated in the additional heat exchange section 20 radiates heat through the additional heat exchange section 20, but it acts in the direction of increasing the density and further Since the additional heat exchange section 20 is located above the water surface of the water storage tank 23, it is possible to prevent the high temperature water in the upper part of the water storage tank 23 from flowing to the heating exchange section 20, Heat radiation loss of water in the water storage tank 23 can be eliminated.

As explained above, according to the present invention, an additional heat exchange part is provided inside the heat exchange part for exchanging heat between gas and water, in which the water inlet is connected to the upper part of the water storage tank, and the water outlet is connected to the lower part. The heat exchanger and burner are arranged in a position above the water storage tank, and configured to forcibly supply the water in the upper part of the water storage tank to the water inlet of the additional heat exchange section, so that the heat exchanger and the burner are integrated into one unit. 2
Since the present invention enables two functions, the entire device can be significantly downsized compared to conventional devices, and an increase in cost can be prevented. In addition, the additional heat exchange section provides the advantage of reducing the temperature difference between the upper and lower portions.

Furthermore, since the lower part of the additional heat exchange part is opened to the upper part of the water storage tank, and the upper part is opened to the lower part of the water storage tank, and the additional heat exchange part is located above the water storage tank, the additional heat exchange part is It is possible to eliminate heat dissipation loss through the heat exchanger, resulting in an energy-saving effect.

[Brief explanation of the drawing]

Figure 1 is a schematic layout of the burner in the heat exchanger of a conventional water heater with additional heating, and Figure 2 is an example of a conventional hot water heater with a built-in heat exchanger. It is a schematic sectional view of a water heater. 12... Burner 14... Heat exchange part 20...
・Additional heat exchange section 21...Additional heating pipe 22
... Refill pipe 23 ... Water storage tank 24
...Pump agent Shin Kuzuno (#Oka or 1 person)

Claims (1)

[Claims] In a heat exchanger equipped with a heat exchange section that exchanges heat between water flowing inside and an external gas, an additional heat exchange section is provided in which a water inlet is connected to the upper part of the water storage tank and a water outlet is connected to the lower part of the water storage tank. A supply means is provided inside the heat exchanger so as to be located above the storage tank, and forcibly supplies the water in the upper part of the water storage tank to the water inlet of the additional heat exchanger. Features of heat exchanger.