JPH08121798A - Circulation type water heater - Google Patents

Abstract

PURPOSE: To reduce the piping space and the piping execution cost in a circulation type water heater in which a combination faucet is used at a hot water supply position. CONSTITUTION: A hot water supply tube 4 from a hot water supply heat source equipment 1 to a hot water supply position 3 and a hot water return tube 5 from the position 3 to the equipment 1 are provided. A circulation pump 6 is provided at the return tube. A first water supply tube 7 is connected to the downstream side of the pump 6, a combination faucet 2 is provided at the position, its hot water side is connected to the supply tube, and the water supply side is connected to the return tube. Further, the supply tube is connected to the return tube via a check valve 11, and a second water supply tube 13 provided with a switching valve 14 is connected to the upstream side of the pump of the return tube. Thus, since the return tube can be used also as the supply tube, the number of tubes from the equipment 1 to the position 3 can be reduced, and the piping space and the piping execution cost can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circulation type hot water supply device which is often applied to medium to large scale hot water supply systems.

[0002]

2. Description of the Related Art In a medium to large-scale hot water supply system, even if the distance from the hot water supply heat source device to the hot water supply location is long, hot water is supplied immediately after the faucet (water tap) is opened. A circulation type (double pipe type) hot water supply device provided with a hot water return pipe for circulation from a location to a hot water heat source device is often used. In the circulation type hot water supply apparatus, in which a hot and cold water mixing faucet is used at a hot water supply location, for example, it is configured as shown in FIG. That is, the circulation type hot water supply device shown in FIG.
A hot water supply pipe 4 from the hot water supply heat source device 1 to a hot water supply part 3 provided with a hot and cold water mixing faucet 2, and a hot water supply return pipe 5 that continuously returns from the hot water supply part 3 to the hot water supply heat source device 1 from the end of the hot water supply pipe 4. , A circulation pump 6 provided in the hot water supply return pipe 5, a water supply pipe 7 that joins the hot water supply return pipe 5, and a water supply pipe 8 that reaches the hot water supply point 3. The hot water side of the hot and cold water mixing faucet 2 is the hot water supply pipe. 4 and the cold water side is connected to the water supply pipe 8. Reference numeral 9 is a flow rate sensor, and 10 is a controller for controlling the hot water supply heat source device 1, the circulation pump 6 and the like.

In such a circulating type hot water supply apparatus, when hot water is loaded, a high temperature (60 to 80) preset from the hot water supply heat source device 1 is set.
Hot water of (° C.) is supplied to the hot water supply point 3 through the hot water supply pipe 4, and the high temperature hot water and cold water supplied from the water supply source through the water supply pipe 8 are mixed by the hot and cold water mixing faucet 2 to obtain a required temperature (generally, (40 ℃) In addition, when there is no hot water from the hot water supply point 3, there is a warming operation in which a certain amount of warm water is circulated in order to keep the hot water temperature in the circulation system.

[0004]

In the conventional circulating type hot water supply apparatus using the hot and cold water mixing faucet, as described above, the hot water supply pipe, the hot water return pipe and the hot water supply pipe are laid from the hot water supply heat source side to the hot water supply point. Therefore, the piping space and piping construction cost are large. Accordingly, an object of the present invention is to solve such a problem.

[0005]

In order to solve the above-mentioned problems, the present invention provides a hot water supply pipe from the hot water supply heat source device to the hot water supply point, and a hot water supply return pipe from the hot water supply point to the hot water supply heat source device. A circulation pump is provided in the hot water supply return pipe, a first water supply pipe is connected to the downstream side of the hot water supply pipe, a hot and cold water mixing faucet is provided at a hot water supply location, and the hot water side is connected to the hot water supply going pipe and the water supply side is hot water supply. It is connected to the return pipe, the hot water supply pipe and the hot water return pipe are connected via a check valve, and a second water supply pipe having an opening / closing valve is connected upstream of the circulation pump of the hot water return pipe. We propose a circulating water heater.

According to the present invention, in the above structure,
The second water supply pipe is configured as a bypass pipe for the hot water supply return pipe that bypasses the circulation pump, or the second water supply pipe is configured as a water supply pipe that is connected from the water supply source to the hot water supply return pipe on the upstream side of the circulation pump. Suggest to do.

[0007]

When the hot and cold water mixing faucet at the hot water supply point is opened, cold water flows from the first water supply pipe to the hot water supply return pipe downstream of the circulation pump, and this cold water is heated by the hot water supply heat source device, The hot water of a predetermined temperature can be supplied to the hot water side of the hot and cold water mixing faucet through the hot water supply pipe.

At the same time, when the circulation pump is stopped and the on-off valve is opened, cold water also flows into the hot water supply return pipe upstream of the circulation pump from the second water supply pipe, and the cold water passes through the hot water supply return pipe. It can be fed to the cold water side of the mixing tap.

Since the hot water supply pipe and the hot water return pipe are connected via the check valve, the supply of cold water through the hot water supply return pipe does not hinder the supply of hot water through the hot water supply pipe. In this way, the hot water and the cold water supplied to the hot and cold water mixing faucet through the hot water hot water supply pipe and the hot water hot water return pipe, respectively, can be mixed and discharged as hot water of a predetermined temperature.

When there is no hot water coming out of the hot and cold water mixing faucet at the hot water supply point, the circulation pump is operated, and the second water supply pipe is shut off by closing the on-off valve and the hot water is driven by the circulation pump. It becomes possible to circulate by flowing from the outgoing pipe side to the hot water supply return pipe side through the check valve, and it is possible to perform a heat retention operation by circulation.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.
FIG. 1 is a system diagram schematically showing a first embodiment of a circulating hot water supply apparatus to which the present invention is applied, and the same components as those of the conventional circulating hot water supply apparatus shown in FIG. Attached. Reference numeral 1 is a hot water supply heat source machine, and this hot water supply heat source machine 1 is
In contrast to the hot water storage type hot water supply heat source machine that has a large amount of retained water, it is composed of an instantaneous hot water supply heat source machine that can change the temperature of hot water to be supplied in a short time. Reference numeral 2 is a hot and cold water mixing faucet installed in the hot water supply point 3, and this hot and cold water mixing faucet 2 has, for example, an element responsive to temperature and pressure built into the hot and cold water mixing valve, and the temperature set by operating a temperature control handle or the like. It is preferable to use a thermostat type hot and cold water mixing tap that automatically adjusts the mixing ratio of hot water and cold water so that

Reference numeral 4 is a hot water supply pipe from the hot water supply heat source device 1 to the hot water supply point, reference numeral 5 is a hot water supply return pipe from the hot water supply place 2 to the hot water supply heat source device 1, and a circulation pump 6 is provided in the hot water supply return pipe 5. A first water supply pipe 7 leading to the water supply is connected to the downstream side thereof, and a flow rate sensor 9 is provided in the first water supply pipe 7. The hot water supply pipe 4 and the hot water supply return pipe 5 are connected on the hot water supply site 2 side via a check valve 11 to form a circulation path. That is, the check valve 11 is provided from the hot water supply pipe 4 side to the hot water return pipe 5
It is installed so that water flows only to the side. The hot water side of each hot and cold water mixing faucet 2 is connected to the hot water supply going pipe 4 via the connection pipe 12h, and the cold water side is connected to the hot water supply return pipe 5 via the connection pipe 12c.

On the other hand, a bypass pipe 14 is connected to the hot water supply return pipe 5 as a second water supply pipe so as to bypass the circulation pump 6, and the bypass pipe 13 is used to open and close an electromagnetic valve, an electric valve or the like. A valve 14 is provided. The opening / closing valve 14 is configured to control opening / closing by the control device 10 that controls the hot water supply heat source device 1 and the circulation pump 6. In addition, a check valve and the like are installed on the downstream side of the first water supply pipe 7 and the circulation pump 6 of the hot water supply return pipe 5, if necessary, but they are not shown.

When the hot and cold water mixing faucet 2 of the hot water supply point 3 is opened in the above configuration, cold water corresponding to the flow rate on the hot water side flows into the hot water supply return pipe 5 from the first water supply pipe 7 and the flow rate sensor 9 is activated. Generates a flow rate output. Therefore, the control device 10 detects the generation of the hot water supply load based on this flow rate output, stops the operation of the circulation pump 6, opens the on-off valve 14, and controls the hot water supply heat source device 1 to handle the load operation.

In this state, part of the cold water flowing from the first hot water supply pipe 7 into the hot water supply return pipe 5 flows through the hot water supply heat source device 1 to the hot water outgoing pipe 4 side, and the other part of the second hot water supply pipe 13 It flows through to the hot water supply return pipe 5 side. At this time, since the hot water supply pipe 4 and the hot water supply return pipe 5 are connected via the check valve 11, the water pressure transmitted through the hot water supply return pipe 5 is not applied in the direction of the hot water supply pipe 4. Therefore, even if the water pressure in the hot water supply pipe 5 is reduced through the heat exchange section of the hot water supply heat source device 1, there is no problem in the flow of hot water toward the hot water supply point 2. In this way, hot water heated to a predetermined temperature flows through the hot water supply pipe 4 and at the same time, the first and second water supply pipes 7, 7,
The cold water that has passed through 13 flows and is supplied to the hot and cold water mixing faucet of the hot water supply point 3, and the temperature is adjusted to the operating temperature by mixing and the hot water is discharged.
The flow of hot water and cold water in this state is shown by the two-dot chain line arrow in the figure.

In the above state, when the hot and cold water mixing faucet 2 is closed, the flow rate output of the flow rate sensor 9 is lost, so the control device 10 closes the on-off valve 14 to shut off the second water supply pipe 13 and turn on the circulation pump 6. Operate and hot water source 1
Is controlled to correspond to the warming operation.

In this state, the hot water driven by the circulation pump 6 flows from the hot water supply return pipe 5 through the hot water supply heat source device 1 to the hot water supply pipe 4 and passes through the check valve 11 at the hot water supply point 3 side to return the hot water supply pipe 5. Then, it flows through the hot water supply return pipe 5 and returns to the circulation pump 6 for circulation. Therefore, the hot water in the hot water supply pipe 4 and the hot water supply return pipe 5 can be maintained at a predetermined temperature by appropriately operating the hot water supply heat source device 1 along with the circulation. The flow of hot water and cold water in this state is shown by solid arrows in the figure.

Next, FIG. 2 is a system diagram schematically showing a second embodiment of the circulating hot water supply apparatus to which the present invention is applied.
The second embodiment is different from the first embodiment shown in FIG. 2 only in the specific configuration of the second water supply pipe. Therefore, the same components as those in the embodiment of FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. This second
In the embodiment, the second water supply pipe is configured as the water supply pipe 15 connected to the hot water supply return pipe 5 on the upstream side of the circulation pump 6 from the water supply source similarly to the first water supply pipe 7.

In this embodiment, since all the cold water flowing through the first water supply pipe 7 flows through the hot water supply heat source device 1 to the hot water supply pipe 4, the feedforward of the hot water supply heat source device 1 using the flow rate output of the flow rate sensor 9 is performed. Easy to control.

[0020]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, in a circulation type hot water supply apparatus using a hot and cold water mixing tap at a water supply point, it is possible to use both the hot water return pipe and the water supply pipe. There is an effect that the number of pipes can be reduced, and the piping space and the piping construction cost can be reduced.

[Brief description of drawings]

FIG. 1 is a system diagram schematically showing the configuration of a first embodiment of a circulating hot water supply apparatus to which the present invention is applied.

FIG. 2 is a system diagram schematically showing a configuration of a second embodiment of a circulating hot water supply apparatus to which the present invention is applied.

FIG. 3 is a system diagram schematically showing a configuration of a conventional example of a circulation type hot water supply device.

[Explanation of symbols]

 1 Hot water supply heat source device 2 Hot water / water mixing faucet 3 Hot water supply location 4 Hot water supply pipe 5 Hot water return pipe 6 Circulation pump 7 First water supply pipe 8 Water supply pipe 9 Flow rate sensor 10 Control device 11 Check valve 12h, 12c Connection pipe 13 Bypass pipe (Second water supply pipe) 14 Open / close valve 15 Water supply pipe (second water supply pipe)

Claims (3)

[Claims] 1. A hot water supply pipe from the hot water supply heat source device to the hot water supply point and a hot water supply return pipe from the hot water supply point to the hot water supply heat source device are provided, and a circulation pump is provided to the hot water supply return pipe, and a first pump is provided downstream thereof. Connect the water supply pipe, provide a hot and cold water mixing tap at the hot water supply point, connect the hot water side to the hot water supply pipe and the water supply side to the hot water return pipe, and connect the hot water supply pipe and the hot water return pipe with a check valve. The circulating hot water supply device is characterized in that the second hot water supply pipe having an open / close valve is connected to the hot water supply return pipe upstream of the circulation pump. 2. The circulating hot water supply apparatus according to claim 1, wherein the second water supply pipe is configured as a bypass pipe of a hot water supply return pipe that bypasses the circulation pump. 3. The circulating hot water supply apparatus according to claim 1, wherein the second water supply pipe is configured as a water supply pipe connected from the water supply source to the hot water supply return pipe on the upstream side of the circulation pump.