JP3306162B2 - High efficiency water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-efficiency hot water supply apparatus having a two-stage heat exchanger for recovering waste heat.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional high-efficiency hot water supply apparatus of this type, in which a heat exchanger for hot water supply heated by a gas burner 1 is divided into two upper and lower stages 2a and 2b, and an upper stage is provided at an intermediate portion. A receiving tray 3 for receiving condensed water generated in the heat exchanger 2a is provided, and a neutralizer 1 is connected to a drain pipe 7 connected to the receiving tray 3.
1 is interposed. In this method, exhaust gas normally discarded at 200 ° C. is passed through a heat exchanger 2a added at the upper stage to recover exhaust heat until the exhaust gas temperature becomes 100 ° C. or less, and condensed water generated at that time is N in exhaust gas
Since Ox and SOx are dissolved and become strongly acidic, they are received by the receiving tray 3 and neutralized by the condensed water neutralizer 5 so that they do not corrode the lower heat exchanger 2b and the gas burner 1. Drains to sewage.

[0003]

However, in the above-mentioned conventional structure, the condensed water neutralizer 11 is large and requires a large installation space. The gaps are liable to be clogged by oxides, and have a problem of severe wear. The present invention aims to provide a highly efficient water heater can it to reduce the size of the neutralizer to eliminate the problems set forth above.

[0004]

As shown in FIG. 1, a high-efficiency hot-water supply apparatus according to the present invention divides a hot-water supply heat exchanger heated by a gas burner 1 into upper and lower two-stage heat exchangers 2a and 2b. A receiving tray 3 for receiving condensed water generated in the upper heat exchanger 2a is provided, an ejector 6 is interposed in a bathtub hot water supply pipe 5 branched from a hot water supply pipe 4, and drainage from the receiver 3 is provided at an inlet of the ejector 6. by connecting tube 7, Rutotomoni allowed mixed condensate in the hot water supplied to the tub 8,
The overflow pipe 10 of the water storage tank 9 interposed in the drain pipe 7 is connected to a neutralizer 11 so that excess condensed water is neutralized and then discharged to the outside.

[0005]

In the above construction, when hot water is supplied to the bathtub, the condensed water can be sucked by the ejector 6 and mixed with the hot water in the bathtub 8, so that the capacity of the condensed water neutralizer 11 can be reduced and the size can be reduced. In this case, the condensed water is a strong acid having a PH value = 3, for example, the amount of condensed water generated by one “hot water streak” is about several tens of milliliters, while the amount of water in a bathtub is usually about 15 ml.
About 0 liters of water is used, and the amount of water used for bathing in ordinary households is about half of the total usage,
The condensed water is diluted to about 1000 to 2000 times, and has a PH value of 6 or more, so that there is no problem for drinking. Also, while only the hot water tap 13 is used, the condensed water is stored in the hot water storage tank 9 and can be digested when the bathtub is used, so that the neutralizer 11 can be further downsized. Further, if the shower hot water supply pipe 12 is branched from the downstream side of the condensed water suction ejector 6 so that the condensed water can be diluted by the bathtub hot water supply pipe 5 even in the summertime when showers are frequently used, the use of the water storage tank 9 can be improved. Therefore, the neutralizer 11 can be omitted.

[0006]

FIG. 1 shows an embodiment of the present invention, in which a heat exchanger for hot water supply heated by a gas burner 1 has two upper and lower stages.
a, 2b, hot water is 80-90 ° C at the bottom
Exhaust gas heated to around 200 ° C
In the upper stage, tap water is preheated to lower the temperature to, for example, 70 to 90 ° C., and at that time, water vapor contained in the exhaust gas is condensed and provided between the upper and lower heat exchangers 2a and 2b. After flowing down to the receiving tray 3 and temporarily stored in the water storage tank 9, it is sent to the injection port of the ejector 6 by the drain pipe 7. On the other hand, a bathtub hot water supply pipe 5 is branched from the hot water supply pipe 4 passing through the heat exchangers 2a and 2b. The bathtub hot water supply pipe 5 is provided with an ejector 6 for condensed water suction via a check valve 14, and this ejector A drain pipe 7 from the tray 3 is connected to the inlet 6. The ejector has an injection passage opened from the side in a narrow passage having a reduced cross-sectional area and an increased flow velocity. In this case, the condensed water is drawn into hot water supplied to the bathtub 8 by tap water pressure. It was done.

[0007] An overflow pipe 10 is connected to the upper part of the water storage tank 9, and condensed water is accumulated in the water storage tank 9 while the hot tub 13 is used without using the bathtub 8. The condensed water overflows and is sent to a neutralizer 11 where it is neutralized and then discharged outside. Also, a shower hot water supply pipe 12 branches off from the bathtub hot water supply pipe 5 on the downstream side of the ejector 6, and even in a home where a shower is frequently used without using a bathtub in summer or the like, condensed water is supplied to the bathtub hot water supply pipe 5 as in winter. In this case, the neutralizer 11 can be omitted according to the user's selection.

In the present invention , a so-called carbonated bath function is provided for dissolving carbon dioxide in exhaust gas in hot water in a bathtub. That is, a second ejector, that is, an exhaust gas suction ejector 16 is disposed downstream of the junction of the bathtub hot water supply pipe 5 and the shower hot water supply pipe 12 through a “hot water beam” solenoid valve 15, and the upper and lower heat sources are disposed. A part of the exhaust gas that has passed through the exchangers 2a and 2b is introduced into the injection port of the ejector 16, and a steam separator 17 is further interposed downstream. As the steam separator 17, an air release valve or a water storage tank having an air release hole in the upper part can be used. In the pipe between the ejector 16 and the steam separator 17,
The carbon dioxide gas in the exhaust gas is dissolved in the warm water, and the surplus gas is discharged from the steam separator 17 to the outside. If the neutralizer 11 is omitted, the exhaust gas may be sucked from the condensed water suction ejector 6, so that even when the exhaust gas suction ejector 16 is not used, the steam separator 17 must be provided. There is.

[0009]

According to the present invention as described above, on the condensed water generated due to the high efficiency water can be mixed into hot water bath by suction by ejector at bathtub hot water
The condensate is stored in a hot water storage tank while only the hot water tap is used.
Can be digested when using the bathtub.
It requires a large installation space,
The condensed water neutralizer, which was severely worn, can be downsized.
There is an advantage of that.

[Brief description of the drawings]

FIG. 1 is a system diagram of one embodiment of the present invention.

FIG. 2 is a system diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas burner 2a Upper heat exchanger 2b Lower heat exchanger 3 Receiving tray 4 Hot water supply pipe 5 Bath tub hot water pipe 6 Ejector for condensed water suction 7 Drain pipe 8 Bath tub 9 Water storage tank 10 Overflow pipe 11 Neutralizer 12 Shower hot water pipe 13 Hot water tap 14 Check valve 15 "Hot water" solenoid valve 16 Ejector for exhaust gas suction 17 Steam-water separator

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F24H 9/00 A47K 3/00 F24H 1/10-1/14

Claims (1)

(57) [Claims] 1. A hot water supply heat exchanger heated by a gas burner.
Is divided into upper and lower stages, and generated in the middle part by the upper heat exchanger
With a receiving tray to receive condensed water from the hot water supply pipe
An ejector is interposed in the hot tub hot water supply pipe
By connecting the drain from the pan to the
And mix the above condensed water into the hot water supplied to the bathtub.
At the same time, a water storage tank is interposed in the drainage pipe,
Connect the overflow pipe of the
That water is neutralized and then discharged to the outside
High efficiency water heater.