JPS6011394Y2 - solar water heater - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a solar water heater.

A conventional example of a fixed-temperature hot water sampling type solar water heater is shown in Fig. 1.

This solar water heater includes a heat collector 3 that uses solar heat to heat water supplied from a water supply tank 1 through a water supply pipe 2 by utilizing the water level difference, and a heat collector 3 that heats water supplied from the water supply tank 1 through a water supply pipe 2 with solar heat, and a hot water supply pipe 4 that heats water in the heat collector 3. A solenoid valve 6 provided in the middle of the hot water sampling pipe 4, and a temperature sensor 7 provided near the outlet of the heat collector 3 to detect the temperature of the hot water in the heat collector 3. When the temperature sensor 7 detects that the water temperature in the heat collector 3 has reached a predetermined set temperature, the controller 8 responds to this detection signal and gives an opening command to the electromagnetic valve 6, so that the temperature is always maintained at the predetermined temperature. The water supply tank 1 is arranged above the heat collector 3, and the heat collector 3 is arranged above the hot water storage tank 5, and the water supply tank 1 is arranged above the heat collector 3. Water is supplied from the heat collector to the heat collector 3 and hot water is drawn from the heat collector 3 to the hot water storage tank 5 by using only the water level difference without using power.

In the figure, 9 is an air vent valve, and 10 is a hot water supply pipe.

However, in such a configuration, if the hot water stored in the hot water storage tank 5 is not used and remains until the next morning, the temperature of the remaining hot water will drop significantly, and the temperature of the hot water drawn from the heat collector 3 will be lower than the predetermined setting. Even if the hot water is maintained at the same temperature, it mixes with the low-temperature remaining hot water in the hot water storage tank 5, making it impossible to supply hot water at a predetermined constant temperature for a while, which has the disadvantage that the effect of constant temperature hot water sampling is halved.

Therefore, an object of this invention is to provide an easy-to-use solar water heater that has a simple configuration that prevents the constant-temperature hot water supply operation from being impaired due to a drop in the temperature of the remaining hot water in the hot water storage tank.

An embodiment of this invention is shown in FIG.

That is, in the conventional example, this solar water heater has the following features:
A three-way valve 11 is arranged in the middle of a water supply pipe 2 that connects a heat collector 3 and a water supply tank 1, and this three-way valve 11 and the hot water storage tank 5 are connected by a circulation pipe 13 having a circulation pump 12 in the middle. Then, when the temperature of the remaining hot water in the hot water storage tank 5 falls below a predetermined set temperature and the temperature in the heat collector 3 is higher than the hot water temperature in the hot water storage tank 5, the circulation pump 12 is driven to remove the remaining hot water. The hot water is returned to the heat collector 3 through the three-way valve 11 and heated again.

A temperature sensor 14 is provided in the lower layer of the hot water storage tank 5 to detect the temperature of the hot water stored in the hot water storage tank. 5, the controller 8' operates to drive the circulation pump 12, and at the same time, the three-way valve 11 is switched from the water tank 1 to the flow path direction A of the collector 3.
From there, the flow direction is switched from the circulation pump 12 to the flow path direction B of the heat collector 3.

In addition, in the hot water storage tank 5, there is a separate hot water storage tank 5.
A water level sensor 15 is arranged to detect the water level of the circulation pump 12, and a detection signal from the water level sensor 15 is used to safely prevent the circulation pump 12 from operating when the water level drops to a level that is inconvenient for driving the circulation pump 12. Measures are being taken.

The water level sensor 15 also detects when the hot water storage tank 5 is full of water, and serves to prevent overflow.

The other configurations are the same as those of the conventional example.

The operation of this solar water heater is as follows.

(1) In the initial state, the flow path of the three-way valve 11 is set in the A direction (water supply tank 1 → heat collector 3), and city water flows from the water supply tank 1 through the water supply pipe 2 to the heat collector. 3.

(2) When the water in the heat collector 3 receives solar heat and is heated to the hot water sampling temperature set in the controller 8', the controller 8' receives a detection signal from the temperature sensor 7 and controls the hot water sampling valve 6. A command is given to open the tap, hot water from the heat collector 3 is drawn into the hot water storage tank 5 via the hot water sampling pipe 4, and when the hot water storage tank 5 is full, the water level sensor 15 detects its upper limit level and the control is performed. Vessel 8
The controller 8' issues a command to close the hot water sampling valve 6, and the hot water sampling is stopped.

(3) If hot water remains in the hot water storage tank 5 at the end of the day's hot water supply, the temperature of this remaining hot water will drop significantly by the next day due to heat radiation.

When the temperature sensor 14 detects that the temperature of the remaining hot water is below the predetermined set temperature and the temperature in the heat collector 3 is higher than the temperature of the hot water in the hot water storage tank 5, the controller 8'
gives a command to the circulation pump 12 and the 3-way valve 11, the circulation pump 12 is driven, and at the same time the 3-way valve 11 switches the flow path in the B direction (circulation pump 12 - heat collector 3) to close the hot water storage tank. The low-temperature residual hot water from No. 5 flows through the reflux pipe 13 and 3-way valve 1.
1 and then returned to the heat collector 3, where it is heated again by solar heat.

However, when the water level in the hot water storage tank 5 is at a predetermined low level that is inconvenient for driving the circulation pump 12, the water level sensor 15 detects this, and the controller 8' receives this detection signal and drives the circulation pump 12. to prevent

(4) When the temperature of the hot water in the hot water storage tank 5 rises to a predetermined temperature due to the circulation operation performed through the circulation pipe 13, the controller 8' commands the circulation pump 12 to stop based on the detection signal of the temperature sensor 14, and issues a command to the three A flow path switching command is issued to each valve 11, and thereafter the normal water supply operation from the water supply tank 1 to the heat collector 3 is resumed.

With this configuration, the temperature of the remaining hot water left in the hot water storage tank 5 decreases, and even if hot water is taken at a constant temperature the next day, it mixes with the low-temperature residual hot water and cannot supply hot water at a specified constant temperature. This can be avoided by adding a simple forced circulation configuration, and constant temperature hot water supply can be performed smoothly.

In addition, heating of the remaining hot water by forced circulation is temporary, and thereafter the operation is switched to normal hot water sampling operation, so that the energy required for circulating the remaining hot water is not required so much, which is economical.

Another embodiment of this invention is shown in FIG.

That is, in the above embodiment, this solar water heater has the following features:
The path for circulating the remaining hot water in the hot water storage tank 5 to the three-way valve 11 is configured as follows.

A first reflux pipe 13 having an auxiliary hot water storage tank 16 disposed above the heat collector 3 and having a circulation pump 12 in the middle.
'a, the bottom of the hot water storage tank 5 and the auxiliary hot water storage tank 16
Further, the bottom of the auxiliary hot water storage tank 16 and the three-way valve 11 are connected by a second reflux pipe 13'b.

When the temperature of the remaining hot water in the hot water storage tank 5 is below a predetermined temperature, the controller controls the driving of the circulation pump 12 and switching the flow path of the three-way valve 11 in the direction B' (auxiliary hot water storage tank 16 - heat collector 3). The configuration performed by the command 8'' is the same as that of the previous embodiment.

With this configuration, the remaining hot water in the hot water storage tank 5 can be temporarily stored in the auxiliary hot water storage tank 16, and the circulation pump 12 can be operated continuously until the auxiliary hot water storage tank 16 is full. operation efficiency will be increased.

Incidentally, in the case of the above embodiment, the remaining hot water pumped out from the hot water storage tank 5 by the circulation pump 12 is directly supplied to the heat collector 3, so the hot water is not drawn until the predetermined hot water temperature is reached in the heat collector 3. During this period, circulation pump 1
However, in this embodiment, the circulation pump 12 works only to recirculate the remaining hot water, which is extremely efficient. .

Other effects are the same as in the previous embodiment.

As described above, the solar water heater of this invention consists of a collector that heats supplied water using solar heat, a water supply pipe with a three-way valve disposed in the middle that introduces water to the collector, and a hot water pipe. a hot water storage tank that receives hot water from the heat collector via a hot water storage tank; and a constant temperature tank that is installed in the middle of the hot water collection pipe and opens when the hot water temperature of the heat collector reaches a predetermined temperature or higher to open the hot water collection pipe. A hot water sampling valve connects the hot water storage tank and the three-way valve, and when the hot water temperature in the hot water storage tank drops by a predetermined temperature, a circulation pump provided in the middle collects the hot water in the hot water storage tank through the three-way valve. Because it is equipped with a return path that returns water to the heater, the simple forced circulation configuration effectively prevents the smooth operation of constant-temperature hot water extraction and constant-temperature hot water supply from being impaired due to a drop in the temperature of the remaining hot water in the hot water storage tank. This has the effect that it can be used as an easy-to-use solar water heater.

[Brief explanation of the drawing]

FIG. 1 is a schematic system diagram showing a conventional example, FIG. 2 is a schematic system diagram showing one embodiment of this invention, and FIG. 3 is a schematic system diagram showing another embodiment of this invention. 1... Water supply tank, 2... Water supply pipe, 3... Heat collector, 4... Hot water sampling pipe,
5... Hot water storage tank, 6... Solenoid valve (constant temperature hot water sampling valve), 7, 14... Temperature sensor, 8
', 8''...Controller, 9...Air bleed valve, 10...Hot water pipe, 11...3-way valve, 12...・Circulation pump, 13.13'a, 1
3'b...reflux pipe, 15...water level sensor, 16...auxiliary hot water storage tank.

Claims (3)

[Scope of utility model registration request] (1) A heat collector that heats the supplied water with solar heat,
A water supply pipe with a three-way valve disposed midway to introduce water to the heat collector; a hot water storage tank that receives hot water from the heat collector via a hot water sampling pipe; A constant-temperature hot water sampling pipe that is opened to release the hot water sampling pipe when the water temperature in the heating device reaches a predetermined temperature or higher, and a constant temperature hot water sampling pipe that connects the hot water storage tank and the three-way valve and is connected to the hot water storage tank when the hot water temperature exceeds a predetermined set temperature. a reflux path in which hot water in the hot water storage tank is returned to the heat collector via the three-way valve using a circulation pump provided midway when the temperature inside the heat collector is higher than the hot water temperature in the hot water storage tank; Equipped with solar water heater. (2) The solar hot water according to claim 1, wherein the circulation path is a circulation pipe that directly connects the bottom of the hot water storage tank and the three-way valve and has the circulation pump disposed in the middle. vessel. (3) The return flow path includes an auxiliary hot water storage tank disposed above the heat collector, and a circulation pipe disposed midway between the hot water storage tank and the auxiliary hot water storage tank to transfer water from the hot water storage tank to the auxiliary hot water storage tank. a first reflux pipe introduced into the tank; and a second reflux pipe that connects the auxiliary hot water storage tank and the three-way valve and causes water stored in the auxiliary hot water storage tank to flow back to the heat collector via the three-way valve. A solar water heater according to claim (1) of the utility model registration, which comprises: