JP5210195B2 - Hot water storage water heater - Google Patents

Description

  The present invention relates to a hot water storage type hot water supply apparatus that heats hot water to be stored by a solar heat collector and a heat pump type heating means.

Conventionally, in this type, the heat medium is heated using solar heat, the heated heat medium is heat-exchanged with the water in the hot water storage tank, and the water in the hot water storage tank is heated. While using hot water, various hot water supply systems that are used in combination with other energy supply sources are also known in order to cope with daily weather and seasonal fluctuations in solar thermal energy usage. By circulating the high-temperature heat medium heated by the heat collector to the heat exchanger provided in the center of the hot water storage tank, the medium temperature water in the hot water storage tank is heated. There has been disclosed a hot water supply system which uses and heats hot water in a hot water storage tank to a set temperature by a heat pump unit, and reduces the amount of heat heated up to the boiling by the amount of heat heated by a solar heat collector during the day. (For example, see Patent Document 1)
JP 2006-153383 A

In addition, by circulating a high-temperature heat medium heated by a solar collector during the day to a heat exchanger provided at the bottom of the hot water tank, the low temperature water near the bottom of the hot water tank is heated, and at night There has been disclosed a hot water supply system in which hot water in a hot water storage tank is heated to a set temperature by a heat pump unit by using electric power in a midnight time zone with a low charge setting. (For example, see Patent Document 2)
JP 2004-92934 A

  By the way, in this conventional type, when the heating means for heating the hot water in the hot water storage tank is a heat pump unit, the low temperature water at the lower part of the hot water storage tank is heated to form hot water and supplied to the upper part of the hot water storage tank to store hot water. The hot water in the hot water tank is heated by circulating the heat medium heated by the solar heat collector in the heat exchanger provided at the center or lower part of the hot water tank. In the lower part, the medium temperature water and the low temperature water around the heat exchanger are heated, and as a result, the whole hot water in the hot water storage tank is heated, and the high temperature water in the upper part of the hot water storage tank cannot be increased.

  In addition, when the heat exchanger is provided in the upper part of the hot water storage tank, high temperature water is stored in the upper part of the hot water storage tank. Therefore, even if the temperature of the heat medium circulating in the heat exchanger is higher than the temperature of the hot water, there is a temperature difference. Because of its small size, heat exchange efficiency is poor, the high-temperature water in the hot water storage tank cannot be increased efficiently, the middle or low temperature water in the middle or lower part of the hot water tank cannot be heated, and the heat exchanger If the temperature of the heat medium circulating in the hot water tank is lower than the temperature of the hot water in the upper part of the hot water tank, the heat medium is heated by the hot water in the upper part of the hot water tank, resulting in a decrease in the temperature of the hot water in the upper part of the hot water tank. It was a thing.

  In order to solve the above-mentioned problems by focusing attention on this point, the present invention is particularly configured as claimed in claim 1. A hot water storage tank for storing hot water, a heating means for heating the hot water in the hot water storage tank, and hot water at the lower part of the hot water storage tank A circulation pump that supplies hot water heated by the heating means to the upper part of the hot water storage tank via a return pipe, and a plurality of hot water storage temperature sensors provided above and below the outer peripheral surface of the hot water storage tank And a solar heat collector that heats the hot water in the hot water storage tank by solar heat, the hot water temperature at the center of the hot water storage tank is medium hot water, and the outlet temperature of the solar heat collector is equal to or higher than the hot water temperature at the top of the hot water storage tank At that time, hot water at the center of the hot water storage tank is supplied to the solar heat collector, and the solar heating operation is started to return the high temperature water heated by the solar heat collector to the upper part of the hot water storage tank. When hot water is equal to or higher than the hot water temperature of the hot water storage tank top, in which a control circuit for stopping the solar heating operation.

  Further, in the hot water storage type hot water supply apparatus according to claim 2, in particular, in the structure of claim 1, the solar heat collector, an intermediate hot water supply pipe connecting the approximate center of the hot water storage tank and the water inlet side of the solar heat collector, A solar heat circuit inlet on / off valve provided on the hot water storage tank side of the intermediate hot water supply pipe, a solar heat circulation pump provided on the solar heat collector side of the intermediate hot water supply pipe, a hot water outlet side of the solar heat collector and hot water storage The solar heating circuit which performs a solar heating operation is comprised by the solar heating hot water pipe which connects a tank upper part, and the solar heating hot water temperature sensor which detects the temperature of the hot water at the hot water outlet side of a solar heat collector.

  Moreover, in the hot water storage type hot water supply apparatus according to claim 3, in particular, in the structure of claim 1, the solar heat collector, an intermediate hot water supply pipe connecting the approximate center of the hot water storage tank and the water inlet side of the solar heat collector, A solar heat circuit inlet on / off valve provided on the hot water storage tank side of the intermediate hot water supply pipe, a solar heat circulation pump provided on the solar heat collector side of the intermediate hot water supply pipe, a hot water outlet side of the solar heat collector and hot water storage Provided in the vicinity of the solar heating hot water pipe that connects the tank upper part, the solar hot water temperature sensor that detects the temperature of the hot water at the hot water outlet side of the solar collector, and the connection part of the hot water storage tank upper part of the solar heating hot water pipe A solar thermal circuit outlet switching valve, a solar thermal circuit outlet temperature sensor for detecting the temperature of hot water flowing into the solar thermal circuit outlet switching valve, provided in front of the solar thermal circuit outlet switching valve of the solar heating hot water pipe, and one end of the solar thermal circuit outlet switching valve Connection A solar heat circuit that performs solar heating operation is configured by a bypass pipe that is connected to a position between the solar heat circuit inlet opening / closing valve of the intermediate temperature water supply pipe and the solar heat circulation pump, and the control circuit is configured to start the solar heating operation. Switch the solar heat circuit outlet switching valve to the bypass pipe side and return the hot water from the solar heat collector to the solar heat collector through the bypass pipe. If over temperature is detected, switch the solar heat circuit outlet switching valve to the hot water storage tank side, return the hot water from the solar heat collector to the upper part of the hot water storage tank, switch the solar heat circuit outlet switching valve to the hot water storage tank side, and then perform solar heating operation When the solar heat circuit outlet temperature sensor detects that the temperature of the hot water storage tank is lower than the hot water temperature, the solar heating operation is stopped.

  According to claim 1 of the present invention, when the hot water in the hot water storage tank is heated up to a set temperature with late-night power at night, the hot water storage tank supplied to the heat pump type outdoor unit so as not to deteriorate the efficiency of heat exchange. 1. The hot water in the hot water storage tank is heated by natural energy solar heat and the hot water is stored in hot water at the lower part while keeping the hot water in the lower part of the hot water, so that it is possible to reduce the power consumption by the boiling operation at midnight power. Is.

  If it is determined that the temperature of the heated hot water does not exceed the hot water storage temperature at the top of the hot water storage tank even if the solar heating operation is performed, the solar heating operation is not performed, so the temperature at the top of the hot water storage tank is low. Hot water is not supplied, and the hot water storage temperature at the top of the hot water storage tank is not lowered.

  According to claim 2 of the present invention, there is provided a hot water storage hot water supply apparatus according to claim 1, wherein the hot water storage tank of the intermediate hot water supply pipe connects the substantial center of the hot water storage tank and the inlet side of the solar heat collector. Since the solar heat circuit inlet on-off valve is provided on the side, when the temperature of the solar heat collector is low, the heat in the hot water storage tank can be prevented from escaping to the solar heat circuit side, and the hot water on the outlet side of the solar heat collector By detecting the temperature with a solar hot water temperature sensor, it is possible to reliably determine that the temperature of the heated hot water does not become equal to or higher than the hot water storage temperature at the top of the hot water storage tank even if the solar heating operation is performed.

  According to claim 3 of the present invention, there is provided a hot water storage type hot water supply apparatus according to claim 1, wherein a bypass pipe is provided in the solar thermal circuit, and the hot water heated by the solar thermal circuit is heated at a hot water temperature above the hot water storage tank for a predetermined time. If the above is detected, the hot water heated by the solar heat circuit is returned to the upper part of the hot water tank from the circulation state in the solar heat circuit by the bypass pipe, so that the hot water having a low temperature is not supplied to the uppermost part of the hot water tank more reliably. The hot water storage temperature is not lowered.

  Furthermore, if the solar circuit outlet temperature sensor detects a temperature below the hot water temperature at the top of the hot water storage tank during the solar heating operation, the solar heating operation is stopped, so that the weather suddenly changes during the solar heating operation and the hot water heated by the solar heating operation is Even if the temperature of the hot water tank is below the hot water temperature, the hot water is not supplied to the uppermost part of the hot water tank, so that the hot water temperature at the uppermost part of the hot water tank is not lowered even if the weather changes suddenly during solar heating operation. .

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing which shows the hot water storage type hot water supply apparatus which attached | subjected one Example of this invention. The block diagram. The flowchart figure of the solar heating operation.

Next, an embodiment of the present invention will be described with reference to the drawings.
1 is a cylindrical hot water storage tank that uses heating means 2 comprising a heat pump type outdoor unit to boil and store hot water in the midnight hours when the unit price of contracted electric power by time zone is low. A water supply pipe 3 for supplying water is connected to the upper part, and a hot water discharge pipe 4 for connecting hot water stored in the hot water to a hot water tap (not shown) is connected to the upper part.

5 is a mixing valve comprising an electric three-way valve connected to a hot water supply pipe 4 on one side, a water supply bypass pipe 6 branched from the water supply pipe 3 on the other side, and a hot water supply pipe 7 on the center. It is a mixing valve that mixes the feed water from the feed water bypass pipe 6 and feeds it at a set hot water supply temperature. From the hot water temperature, the feed water temperature, and the set temperature, the opening degree of the hot water pipe 4 and the feed water bypass pipe The feedforward control for adjusting the opening degree of 6 is performed.

A temperature sensor 8 is also provided in the water supply bypass pipe 6 and serves as a water supply thermistor for detecting the temperature of the water supply. The temperature sensor 8 detects the temperature of the water supply during hot water supply and adjusts the opening of the mixing valve 5, and hot water in the hot water storage tank 1. When the boundary layer is located below the mixing valve 5, the hot water supply is stopped and the mixing valve 5 is set to an opening degree where the outlet pipe 4 and the water supply bypass pipe 6 communicate with each other, and the hot water in the hot water storage tank 1 is balanced. When the convection occurs directly below and flows into the feed water bypass pipe 6, the temperature of the mixed water is detected, and the feed valve 5 is driven to 100% open at the feed water bypass pipe 6 side which is the water side at a predetermined temperature or higher. Thereafter, the mixing valve 5 is controlled by the feedforward control.

Reference numeral 9 denotes a circulation circuit including an outward pipe 10, a return pipe 11, and a circulation pump 12 that connect the hot water storage tank 1 and the heating means 2 so that hot water can be circulated.
13, 14, 15, 16, and 17 are hot water storage temperature sensors provided above and below the outer peripheral surface of the hot water storage tank 1, 18 is a pressure reducing valve provided in the middle of the water supply pipe 3, and 19 is provided in the hot water discharge pipe 4. Pressure relief valve.
A flow sensor 20 is provided in the hot water supply pipe 7 and detects the start / stop of hot water supply by detecting the flow of hot water.

  21 is a solar heat collector, the water inlet side 22 is provided in the approximate center of the hot water storage tank 1, and an intermediate hot water supply pipe 23 is connected to make the hot water in the approximate center in the hot water storage tank 1 into the solar heat collector 21. The intermediate temperature water supply pipe 23 is provided with a solar heat circuit inlet opening / closing valve 24 on the hot water storage tank 1 side, and a solar heat circulation pump 25 is provided on the solar heat collector 21 side.

  Reference numeral 26 denotes a solar heating hot water pipe, one end of which is connected to the hot water outlet side 27 of the solar heat collector 21 and the other end is connected to the ceiling portion of the hot water storage tank 1 to store hot water heated by the solar heat collector 21. It is supplied to the upper part of the tank 1.

  The other end of the solar heating hot water pipe 26 is connected to the ceiling portion of the hot water storage tank 1. A solar thermal circuit outlet switching valve 28 is provided in front of the connecting portion, and the other end is the solar thermal circuit outlet switching valve 28. And a bypass pipe 29 having the other end connected between the solar heat circuit inlet opening / closing valve 24 and the solar heat circulation pump 25 of the intermediate-temperature water supply pipe 23.

  Further, a solar hot water temperature sensor 30 for detecting the temperature of hot water heated by the solar heat collector 21 is provided in the vicinity of the hot water outlet side 27 of the solar heat collector 21, and a solar heat circuit of the solar heated hot water pipe 26. A solar thermal circuit outlet temperature sensor 31 that detects the temperature of the hot water flowing into the solar thermal circuit outlet switching valve 28 is provided at a position before the outlet switching valve 28.

  A solar thermal circuit 32 is formed by the solar heat collector 21, the intermediate hot water supply pipe 23, the solar thermal circulation pump 25, the solar thermal heating hot water pipe 26, and the bypass pipe 29.

  33 is a control circuit composed of a microcomputer. On the input side, a hot water supply temperature setting unit 34 of a remote controller (not shown) and a hot water storage temperature sensor 13 at the uppermost position are connected as a hot water temperature sensor, and a temperature sensor 8 is a water supply temperature sensor. And a flow sensor 20 connected to the hot water supply pipe 7 for detecting the start / stop of hot water supply by detecting the flow of hot water, and connected to the output side as a step motor of the mixing valve 5. The opening degree of the mixing valve 5 is adjusted by controlling the drive amount.

  Further, a boiling temperature setting unit 35 and a hot water storage temperature sensor 17 at the lowest position are connected to the input side of the control circuit 33 as an incoming water temperature sensor, and the hot water storage temperature sensors 13 to 17 reach a boiling temperature. It is connected as a hot water storage sensor that detects the amount of hot water stored in the water, and on the output side, the heating means 2 and the circulation pump 12 are controlled to store hot water heated to the boiling temperature in the hot water storage tank 1. .

  Further, a solar hot water temperature sensor 30 and a solar thermal circuit outlet temperature sensor 31 are connected to the input side of the control circuit 33, and a solar thermal circuit inlet opening / closing valve 24, a solar thermal circuit outlet switching valve 28, and solar heat are connected to the output side. A circulation pump 25 is connected, and the medium temperature water in the approximate center of the hot water tank 1 is sent to the solar heat collector 21 by the solar heat circulation pump 25 and heated to a temperature higher than the high temperature water at the upper part of the hot water tank 1, and the upper part of the hot water tank 1. Hot water is stored in the water.

Next, the operation of the solar heating operation shown in FIG. 3, which is a main part of the present invention, will be described.
As shown in FIG. 3, first, it is determined whether the temperature of the hot water in the substantially central portion of the hot water storage tank 1 is not less than 30 degrees and not more than 50 degrees (S1). It is determined whether the temperature of the outlet hot water at the outlet side 27 of the collector 21 is equal to or higher than the hot water storage temperature at the top of the hot water storage tank 1. (S2)

  If the temperature of the outlet hot water on the outlet side 27 of the solar heat collector 21 is not equal to or higher than the hot water storage temperature at the top of the hot water storage tank 1, the process returns to (S1) and the temperature of the outlet hot water on the outlet side 27 of the solar collector 21 is When the temperature is higher than the hot water storage temperature at the top of the hot water storage tank 1, the solar thermal circuit inlet on / off valve 24 is opened (S3), the solar thermal circuit outlet switching valve 28 is operated to the circuit circulation side (S4), and the solar thermal circulation pump 25 is turned on. Turn it on. (S5)

Thereby, the middle temperature water in the substantially central portion of the hot water storage tank 1 is supplied to the solar heat collector 21, and the hot water in the solar heat circuit 32 is supplied to the solar heat collector 21. When the hot water heated to the upper hot water storage temperature or higher reaches the position of the solar circuit outlet temperature sensor 31 provided in front of the solar circuit outlet switching valve 28 of the solar heating hot water pipe 26, the temperature of the solar circuit outlet switching valve hot water is reached. Is determined to be equal to or higher than the hot water storage temperature at the uppermost part of the hot water storage tank 1 (S6), and it is assumed that the hot water storage temperature at the uppermost part of the hot water storage tank 1 will not be lowered even if supplied The valve 28 is operated to the tank supply side, and the high-temperature water heated by the solar heat collector 21 is supplied to the uppermost part of the hot water storage tank 1.
At this time, in order to supply the hot water heated above the hot water storage temperature at the uppermost part of the hot water storage tank 1 more reliably to the uppermost part of the hot water storage tank 1, the solar heat circuit outlet temperature sensor 31 exceeds the hot water storage temperature at the uppermost part of the hot water storage tank 1. The solar thermal circuit outlet switching valve 28 may be operated to the tank supply side after detecting for a predetermined time.

  When hot water heated by the solar heat collector 21 is supplied to the uppermost part of the hot water storage tank 1, the hot water layer in the upper part of the hot water storage tank 1 moves from the upper part of the hot water storage tank 1 to the central part. When the temperature of the hot water in the hot water storage tank 1 is substantially equal to or higher than the hot water storage temperature in the uppermost part of the hot water storage tank 1 (S8), the solar heat circuit outlet switching valve 28 is switched to the in-circuit circulation side (S9). 25 is turned off (S10), and the solar thermal circuit inlet opening / closing valve 24 is closed (S11), and the solar thermal heating operation is terminated. (S12)

  In (S6), when the hot water temperature of the solar thermal circuit outlet switching valve remains below the hot water storage temperature at the top of the hot water storage tank 1, or when the hot water temperature is higher than the hot water storage temperature at the top of the hot water storage tank 1, When the temperature falls below the uppermost hot water storage temperature, the temperature of the hot water at the outlet 27 side of the solar heat collector 21 was initially equal to or higher than the hot water storage temperature at the uppermost hot water storage tank 1, but then the hot water storage tank 1 is abbreviated. Even if the middle temperature water in the central portion is supplied to the solar heat collector 21, it is determined that the medium temperature water cannot be heated to the hot water storage temperature at the uppermost part of the hot water storage tank 1, and the process proceeds to (S9).

  Also, in (S8), when the temperature of the hot water at the substantially central portion of the hot water storage tank 1 becomes equal to or higher than the hot water storage temperature at the top of the hot water storage tank 1, the solar heating operation is terminated by the heating means 2 comprising a heat pump type outdoor unit at night. When the hot water of the hot water storage tank 1 is heated to the set temperature with the midnight electric power of the heat pump, the heat exchange efficiency deteriorates when the incoming water temperature rises due to the nature of the heat pump, so the hot water storage tank supplied to the heat pump type outdoor unit This is because the lower part of the hot water is low temperature water.

  As described above, when the hot water of the hot water storage tank 1 is heated up to the set temperature with the late-night power at night, the hot water in the lower part of the hot water storage tank 1 supplied to the heat pump type outdoor unit so as not to deteriorate the efficiency of heat exchange. The hot water in the hot water storage tank 1 is heated by natural energy solar heat and the high temperature water is stored, so that the power consumption by the boiling operation at midnight power can be reduced. .

  If it is determined that the temperature of the heated hot water does not exceed the hot water storage temperature at the top of the hot water storage tank 1 even if the solar heating operation is performed, the solar heating operation is not performed. Hot water is not supplied, and the hot water storage temperature at the top of the hot water storage tank 1 is not lowered.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 2 Heating means 10 Outward pipe 11 Return pipes 13, 14, 15, 16, 17 Hot water storage temperature sensor 21 Solar heat collector 33 Control circuit

Claims (3)

  A hot water storage tank for storing hot water, a heating means for heating the hot water in the hot water storage tank, hot water at the bottom of the hot water storage tank is supplied to the heating means via the forward pipe, and the high temperature water heated by the heating means is supplied to the return pipe A circulating pump that returns to the upper part of the hot water storage tank, a plurality of hot water temperature sensors provided above and below the outer peripheral surface of the hot water tank, and a solar heat collector that heats the hot water in the hot water tank by solar heat. When the hot water temperature at the center is medium hot water and the outlet temperature of the solar heat collector is equal to or higher than the hot water temperature at the top of the hot water tank, the hot water at the hot water tank is supplied to the solar heat collector and heated by the solar heat collector. The solar heating operation is started to return the high-temperature water returned to the upper part of the hot water storage tank, and when the hot water at the approximate center of the hot water tank becomes higher than the hot water temperature at the upper part of the hot water tank after starting the solar thermal heating operation, the solar heating operation is stopped. Hot water storage type hot water supply apparatus characterized by comprising a circuit.   A solar heat collector, an intermediate hot water supply pipe connecting the approximate center of the hot water storage tank and the inlet side of the solar heat collector, a solar heat circuit inlet opening / closing valve provided on the hot water storage tank side of the intermediate hot water supply pipe, A solar heat circulation pump provided on the solar collector side of the hot water supply pipe, a solar heating hot water pipe connecting the outlet side of the solar collector and the upper part of the hot water storage tank, and hot water on the outlet side of the solar collector The hot water storage type hot water supply apparatus according to claim 1, wherein a solar thermal circuit for performing a solar thermal heating operation is constituted by a solar thermal hot water temperature sensor for detecting the temperature of the hot water.   A solar heat collector, an intermediate hot water supply pipe connecting the approximate center of the hot water storage tank and the inlet side of the solar heat collector, a solar heat circuit inlet opening / closing valve provided on the hot water storage tank side of the intermediate hot water supply pipe, A solar heat circulation pump provided on the solar collector side of the hot water supply pipe, a solar heating hot water pipe connecting the outlet side of the solar collector and the upper part of the hot water storage tank, and hot water on the outlet side of the solar collector A solar heat outlet temperature sensor for detecting the temperature of the solar heating circuit, a solar heat circuit outlet switching valve provided in the vicinity of the connection portion between the solar heating hot water pipe and the hot water storage tank, and a solar heating system provided before the solar heating circuit outlet switching valve of the solar heating hot water pipe A solar thermal circuit outlet temperature sensor that detects the temperature of the hot water flowing into the circuit outlet switching valve, and one end connected between the solar thermal circuit outlet switching valve and the other end between the solar thermal circuit inlet on-off valve of the medium hot water supply pipe and the solar circulation pump Position of A solar thermal circuit that performs solar heating operation is configured by the connected bypass pipe, and the control circuit switches the solar thermal circuit outlet switching valve to the bypass pipe side at the start of the solar heating operation, and supplies the hot water from the solar heat collector to the bypass pipe. When the solar heat circuit outlet temperature sensor detects the hot water temperature above the hot water tank for a predetermined time from the start of the solar heat operation, switch the solar heat circuit outlet switching valve to the hot water tank side and switch from the solar heat collector. After returning the hot water of the hot water tank to the upper part of the hot water tank and switching the solar heat circuit outlet switching valve to the hot water tank side, stop the solar heat heating operation when the solar heat circuit outlet temperature sensor detects that the temperature of the hot water tank is lower than the hot water temperature The hot water storage type hot water supply apparatus according to claim 1.

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