JP2018031521A - Storage water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater constituted by two pieces of units and capable of preventing freezing by performing a freezing preventive operation even when information on one of the units cannot be obtained due to communication failure of communication means between both of the units.SOLUTION: A storage water heater includes: an external heat source unit; a hot water storage unit having a hot water storage tank; a circulation heating circuit that connects the external heat source unit with the hot water storage tank; circulation means provided in the circulation heating circuit; communication means between both of the units; and control means that can control both of the units through communication made by the communication means. The control means is configure to perform a freezing preventive operation on the basis of a predetermined temperature condition by obtaining a detection temperature of temperature detection means provided in each of both of the units, and when communication failure occurs in the communication means, to ease the temperature condition to perform the freezing preventive operation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hot water storage and hot water supply apparatus that stores hot water heated by an external heat source unit in a hot water storage tank of a hot water storage unit and supplies hot water, and in particular, freeze that prevents hot water from freezing and damaging equipment in the hot water storage and hot water supply apparatus in cold weather The present invention relates to a hot water storage hot water supply apparatus that performs preventive operation.

  2. Description of the Related Art Conventionally, a hot water storage and hot water supply apparatus that stores hot water heated by an external heat source unit in a hot water storage tank built in the hot water storage unit and supplies the stored hot water is widely used. When such a hot water storage hot water supply apparatus is cold, the hot water may freeze and damage the equipment in the hot water storage hot water supply apparatus. Therefore, based on the temperature detected by the temperature sensor provided in the hot water storage hot water supply device and a predetermined temperature condition, the freeze prevention operation is performed when freezing is expected.

  For example, the hot water device of Patent Document 1 prevents freezing by operating a plurality of anti-freezing heaters, circulating hot water in a circulation passage, or operating a heat source device when the temperature is expected to freeze. It is configured as follows. In addition, the connected hot water supply apparatus of Patent Document 2 has a plurality of hot water supply apparatuses connected to each other, and when a temperature at which freezing is expected is reached, the hot water passage of each hot water supply apparatus is opened and a pump is provided so that hot water flows through each hot water supply apparatus. It is configured to operate and prevent freezing.

  The hot water storage hot water supply apparatus is composed of two pieces of an external heat source unit and a hot water storage unit, and may be installed apart from each other. For example, in an apartment house, the external heat source unit is installed on a passage or a veranda, and the hot water storage unit is installed on a pipe shaft. Since the installation environment of the external heat source unit and the installation environment of the hot water storage unit are different, the temperature of the hot water in the external heat source unit may be lower than the temperature of the hot water in the hot water storage unit when the hot water storage hot water supply device continues in the standby state. Therefore, the control means of the hot water storage hot water supply apparatus acquires the detected temperature of hot water of both units using the communication means between the units, and prevents freezing when the temperature is expected to freeze based on a predetermined temperature condition. It is configured to drive.

Japanese Patent No. 4277153 Japanese Patent No. 3906717

  By the way, an abnormality occurs in the communication means between the units, and communication cannot be performed, the control means of the hot water storage hot water supply apparatus cannot acquire the detected temperature of hot water or the like of one unit, and the unit cannot receive the control command of the control means, etc. It may become a state. In this case, the control means performs the freeze prevention operation based on the detected temperature of hot water or the like that can be acquired and the temperature condition corresponding to the detected temperature, but both units are installed apart as described above, and the unit that cannot acquire the temperature is low In such an environment, the hot water may freeze before the start of the freeze prevention operation.

  With respect to the above problem, the hot water device of Patent Document 1 is not a two-piece configuration, but is configured to prevent freezing with other anti-freezing heaters or other means when an abnormality of the anti-freezing heater is detected. The problem is not solved. The connection type hot water supply device of Patent Document 2 has substantially the same installation environment because a plurality of hot water supply devices having the same configuration are installed at locations close to each other, and the above-described problem is unlikely to occur. In addition, it is not possible to prevent freezing of the water heater that cannot receive the command for the freeze prevention operation due to a communication abnormality.

  An object of the present invention is to prevent freezing in a hot water supply apparatus composed of two-piece units even when information on one unit cannot be acquired due to poor communication of communication means between both units. It is providing the hot-water supply apparatus which can do.

  The first invention includes an external heat source unit, a hot water storage unit including a hot water storage tank, a circulation heating circuit connecting the external heat source unit and the hot water storage tank, circulation means provided in the circulation heating circuit, In the hot water storage and hot water supply apparatus provided with the communication means between the units and the control means capable of controlling the both units by communicating with the communication means, the control means detects the temperature detected by the temperature detection means provided in each of the units. The freeze prevention operation is performed based on a predetermined temperature condition, and when the communication means has a communication failure, the freeze condition operation is performed by relaxing the temperature condition.

  According to the said structure, the freeze prevention operation | movement of the hot water storage hot-water supply apparatus comprised by two units is performed based on the temperature detected by each unit, and a predetermined temperature condition. If the temperature detected by one unit cannot be acquired due to communication failure of the communication means, the temperature condition can be relaxed to start the freeze prevention operation at a temperature higher than the predetermined temperature condition, and the temperature can be acquired. Freezing prevention operation is performed based on the detected temperature of the correct unit and relaxed temperature conditions. Therefore, even when a unit that cannot obtain the detected temperature is lower in temperature than a unit that can detect the temperature, freezing can be prevented by the freeze prevention operation, and damage to the device can be prevented.

  In a second aspect based on the first aspect, either the external heat source unit or the hot water storage unit is provided with the control means and the circulation means, and the freeze prevention operation is performed by driving the circulation means. It is characterized by hot water circulation operation.

  According to the said structure, since hot water is circulated in the circulation heating circuit which connects both units and it makes it hard to freeze, freezing can be prevented.

  According to a third invention, in the first or second invention, the external heat source unit is a heat pump, and the hot water storage unit is provided with a combustion type auxiliary heat source machine.

  According to the said structure, since the heat source machine which can heat hot water is provided in both units, hot water can be heated at the time of freeze prevention operation.

  According to the present invention, in a hot water supply apparatus constituted by two-piece units, even when information on one unit cannot be acquired due to poor communication of communication means between both units, freeze prevention operation is performed to prevent freezing. It is possible to provide a hot water supply device capable of performing the above.

It is the schematic of the hot water storage hot-water supply apparatus of this invention. It is a figure which shows the hot water circulation driving | operation. It is a figure which shows the example of a change of the hot water storage hot-water supply apparatus of an Example.

  Hereinafter, modes for carrying out the present invention will be described based on examples.

Initially, the whole structure of the hot water storage hot-water supply apparatus 1 is demonstrated based on FIG.
As shown in FIG. 1, the hot water storage and hot water supply apparatus 1 includes a hot water storage unit 2 having an auxiliary heat source unit 4 and an external heat source unit 3. A communication means 50 is provided between the hot water storage unit 2 and the external heat source unit 3 so that the two units can communicate with each other. The external heat source unit 3 is a heat pump heat source machine (hereinafter referred to as an HP heat source machine), and the auxiliary heat source machine 4 is a combustion type heat source machine.

  The hot water storage unit 2 includes an auxiliary heat source unit 4, a hot water storage tank 5 for storing hot water, a hot water passage 6 connected to the upper end of the hot water tank 5, and a hot water supply connected to the hot water passage 6 to supply hot water to a hot water supply destination. Circulating heating that circulates so as to heat the hot water in the hot water storage tank 5 by the HP heat source unit 3 and store it in the hot water storage tank 5 by branching from the hot water supply passage 7 and the pouring passage 8 that branches from the hot water supply passage 7. A circuit 9, a water supply passage 10 for supplying clean water to the hot water storage tank 5, a mixing valve 16 for mixing hot water and clean water, and a heat exchanger 12 for bath remedy for heating hot water in the bathtub 13A, A hot water supply passage 31 that branches from the auxiliary hot water supply passage 14c and supplies hot water to the heat exchanger 12, a hot water supply circuit 13, a hot water storage controller 11 that performs various controls, an operation remote controller 60, and the like are provided.

  A plurality of hot water storage temperature sensors 5a to 5d are provided at appropriate intervals on the side of the hot water storage tank 5 to detect the temperature of the stored hot water. Although illustration is omitted, the periphery of the hot water storage tank 5 is covered with a heat insulating material that prevents the temperature of the stored hot water from falling.

  The water supply passage 10 has an upstream end connected to a water supply source and a downstream end connected to a lower end portion of the hot water storage tank 5 to supply low temperature hot water from the water supply source to the hot water storage tank 5 and the like. A water supply bypass passage 18 is branched from the water supply passage 10 and connected to the mixing valve 16. In the water supply passage 10, a water supply temperature sensor 19 is provided on the upstream side of the branch portion, and a check valve 20 is provided on the downstream side of the branch portion. A check valve 21 is provided in the water supply bypass passage 18. A hot water discharge bypass passage 22 is branched from the water supply bypass passage 18 and is connected to the hot water supply passage 7 so as to avoid high temperature hot water discharge.

  The hot water outlet passage 6 has an upstream end connected to the upper end of the hot water storage tank 5 and a downstream end connected to the mixing valve 16. The mixing valve 16 is connected to the upstream end of the hot water supply passage 7. The hot water outlet passage 6 is provided with a tank hot water temperature sensor 5f for detecting the temperature of hot water discharged from the hot water storage tank 5.

  The mixing valve 16 adjusts the mixing ratio between the low-temperature clean water supplied from the feed water bypass passage 18 and the high-temperature hot water supplied from the hot water discharge passage 6, and has a temperature set by the user via the operation remote controller 60. Hot water is supplied to the hot water supply passage 7. A hot water supply temperature sensor 23 is provided in the hot water supply passage 7 to detect the hot water supply temperature.

  An on-off valve 8a is provided in the pouring passage 8 branched from the hot water passage 7 and filling the bathtub 13A, and the downstream end of the pouring passage 8 is connected to a bath passage portion 13a described later.

  The downstream end of the memorial hot water passage 31 is connected to a lower auxiliary passage 33 branched from the downstream portion of the water supply passage 10.

  An upper auxiliary passage 14a for supplying hot water to the auxiliary heat source device 4 is branched from the hot water supply passage 6 and connected to the three-way valve 17, and a lower auxiliary passage 33 for supplying low-temperature hot water or clean water to the auxiliary heat source device 4. Is connected to the three-way valve 17, and an auxiliary introduction passage 14 b extending from the three-way valve 17 is connected to the auxiliary heat source unit 4.

  A circulation pump 40 is interposed in the auxiliary introduction passage 14b. The auxiliary hot water passage 14 c through which the high-temperature hot water heated by the auxiliary heat source device 4 is discharged is connected to the hot water passage 6 upstream of the mixing valve 16. The three-way valve 17 can be selectively switched between the hot water storage tank 5 side and the lower auxiliary passage 33 side.

  The circulation heating circuit 9 includes an outgoing passage portion 9a, a return passage portion 9b, and a bypass passage portion 9c that connects them. The upstream passage 9 a has an upstream end connected to the lower end of the hot water storage tank 5, and a downstream end connected to the condensation heat exchanger 36 of the HP heat source unit 3. The return passage portion 9 b has an upstream end connected to the condensation heat exchanger 36 and a downstream end connected to the upper end of the hot water storage tank 5.

  A circulation pump 25, which is a circulation means, is interposed in the forward passage portion 9a, and a circulation temperature sensor 9d is provided in the return passage portion 9b. A switching three-way valve 15 is interposed at a connection point between the forward passage portion 9a and the bypass passage portion 9c. The switching three-way valve 15 can switch the hot water supply passage to be sent to the HP heat source unit 3 between the hot water storage tank 5 side and the bypass passage portion 9c side. When hot water is insufficiently heated, such as immediately after the start of the HP heat source device 3, the hot water heated by the HP heat source device 3 is reheated by setting the switching three-way valve 15 to the bypass passage portion 9 c side. When the heating does not become insufficient, the switching three-way valve 15 is set to the hot water storage tank side, the hot water in the hot water storage tank 5 is heated by the HP heat source unit 3, and the heated hot water is stored in the hot water storage tank 5.

  The heat exchanger 12 for bath remedy heats hot water in the bathtub 13A flowing through the remedy circuit 13 by heat exchange with hot water flowing through the remedy hot water passage 31 branched from the auxiliary hot water passage 14c. An open / close valve 31a is provided in the remedy hot water passage 31 and is closed so that hot water does not flow into the heat exchanger 12 except during bath remedy operation.

  The memorial circuit 13 circulates the hot water in the bathtub 13A so as to be heated in the heat exchanger 12, and the bath passage section 13a for sending the hot water heated in the heat exchanger 12 to the bathtub 13A, and the bathtub 13A It has a bath return passage portion 13b in which a circulation pump 30 for sending hot water to the heat exchanger 12 is interposed.

  The HP heat source unit 3 is controlled by the hot water storage control unit 11 via the HP control unit 34, and a heat pump is obtained by connecting the compressor 35, the condensation heat exchanger 36, the expansion valve 37, and the evaporating heat exchanger 38 through the refrigerant pipe 39. A circuit is configured, and hot water is heated using the refrigerant sealed in the refrigerant pipe 39 and the heat of the outside air.

  The hot water storage control unit 11 includes hot water storage temperature sensors 5a to 5d that are temperature detection means, a circulating temperature sensor 9d, a feed water temperature sensor 19, a hot water supply temperature sensor 23, a mixing valve incoming water temperature sensor 43, an external heat source incoming water temperature sensor 41, and an external heat source hot water outlet. The temperature of each part is acquired by the temperature sensor 42 or the like, and the switching three-way valve 15, the mixing valve 16, the three-way valve 17, the flow rate adjusting valve 26, other valves, the circulation pumps 25, 30, 40, etc. are operated, and the HP heat source machine 3 is a control means of the hot water storage and hot water supply apparatus 1 that controls the hot water supply operation, the hot water storage operation, and the like so that the hot water supply operation and the hot water filling at the set temperature of the hot water supply are performed. The hot water storage control unit 11 acquires the temperature detected by each temperature sensor every predetermined time, for example, every 0.2 seconds.

Next, the freeze prevention operation will be described.
The freeze prevention operation is performed by the water supply temperature sensor 19, the mixing valve incoming water temperature sensor 43, the hot water supply temperature sensor 23, the tank hot water temperature sensor 5 f and the circulating temperature sensor 9 d provided in the hot water storage unit 2. The incoming water temperature, the hot water supply temperature, the tank hot water temperature, the circulating temperature, the incoming heat temperature and the hot water detected by the external heat source incoming water temperature sensor 41, the external heat source hot water temperature sensor 42, and the outside air temperature sensor 44 provided in the HP heat source unit 3, respectively. The hot water storage control unit 11 acquires the temperature and the outside air temperature, and starts the freeze prevention operation according to a predetermined temperature condition.

Here, the predetermined temperature conditions are the following conditions (1) to (8). When one of these conditions is satisfied, the freeze prevention operation is started. (1) to (5) relate to the detected temperature of the temperature sensor provided in the hot water storage unit 2, and (6) to (8) relate to the detected temperature of the temperature sensor provided in the HP heat source unit 3. .
(1) Feed water temperature <5 ° C, detected for 5 seconds continuously (2) Mixing valve water temperature <7 ° C, detected for 5 seconds continuously (3) Hot water supply temperature <7 ° C, detected for 5 seconds continuously (4) Tank discharge temperature <7 ° C, 5 seconds continuously Detection (5) Circulation temperature <5 ° C, detection for 5 seconds continuously (6) External heat source unit incoming temperature <5 ° C, detection for 12 seconds continuously (7) External heat source unit hot water temperature <5 ° C, detection for 12 seconds (8) Outside external heat source unit Temperature <3 ° C Detection for 12 consecutive seconds

When the freeze prevention operation is started, as shown in FIG. 2, the circulating pump 25 is driven to perform a hot water circulating operation in which hot water circulates through the circulation heating circuit 9. It is also possible to circulate hot water heated by operating the HP heat source unit 3 and the auxiliary heat source unit 4. After the hot water circulation operation is continued for a predetermined time (for example, 5 minutes), the operation ends when the following end condition (A) is satisfied or when all the end conditions (B) to (E) are satisfied.
(A) 60 minutes elapsed from the start of hot water circulation operation (B) Circulation temperature <5 ° C Detected for 5 seconds continuously (C) Detected water temperature of external heat source machine ≥ 7 ° C Detected for 20 seconds continuously (D) Temperature discharged from external heat source machine ≥ 7 ° C Continuous Detected for 20 seconds (E) External heat source outside temperature <-15 ° C for 12 consecutive seconds

Next, the operation and effect of the hot water storage hot water supply apparatus 1 of the present invention will be described.
When a communication failure occurs in the communication means 50 between the hot water storage unit 2 and the HP heat source unit 3, the hot water storage control unit 11 provided in the hot water storage unit 2 cannot communicate with the HP heat source unit 3, so that the temperature condition (6) It cannot judge about (8). In this case, the hot water storage control unit 11 starts the hot water circulation operation when any of the temperature conditions (1) to (5) is established. However, even if the temperature conditions (1) to (5) are not established, the temperature conditions (6) to (8) are established if the HP heat source unit 3 and the hot water storage unit 2 are installed at positions separated from each other. There is a possibility that the freeze prevention operation should be started.

  Therefore, the reference of the water supply temperature and the circulation temperature in the temperature conditions (1) and (5) is changed to the high temperature side (for example, 10 ° C.), that is, the temperature condition is relaxed to facilitate the freeze prevention operation. Thereby, the damage of the apparatus by freezing of hot water can be prevented.

  In the freeze prevention operation, hot water is circulated in the circulation heating circuit 9 by operating the circulation pump 25. Since the flowing hot water is difficult to freeze, it is possible to prevent damage to the equipment due to freezing of the hot water.

  In addition, since the HP heat source unit 3 is a heat pump and the hot water storage unit 2 includes the combustion type auxiliary heat source unit 4, each can heat the hot water. Even when the heat pump cannot be operated due to poor communication and the hot water in the circulation heating circuit 9 cannot be heated, the hot water heated by the auxiliary heat source unit 4 is introduced into the circulation heating circuit 9 to perform the hot water circulation operation. As it is done, it is possible to prevent freezing of hot water.

  The freeze prevention operation started when the relaxed temperature condition is established is terminated when the end condition (A) or (B) is established because the temperature on the HP heat source unit 3 side is unknown.

An example in which the above embodiment is partially changed will be described.
[1] The circulation pump 25 may be provided in the HP heat source unit 3 (see FIG. 3). In this case, the HP control unit 34 that controls the HP heat source unit 3 is a control unit of the hot water storage hot water supply device 1 and controls the hot water supply device freeze prevention operation. When the temperature on the hot water storage unit 2 side is unknown due to poor communication, the temperature conditions (6) to (8) are relaxed to facilitate the freeze prevention operation. After the freeze prevention operation is continued for a predetermined time, the operation is terminated when the end condition (A) is satisfied or when all the end conditions (C) to (E) are satisfied.
[2] In the freeze prevention operation, hot water circulation operation may be performed and a freeze prevention heater provided in a hot water passage other than the circulation heating circuit 9 may be operated.
[3] In addition, those skilled in the art can implement the present invention by adding various modifications without departing from the spirit of the present invention, and the present invention includes such modifications. It is.

1 Hot water storage hot water supply device 2 Hot water storage unit 3 External heat source unit (HP heat source machine)
4 Auxiliary heat source machine 5 Hot water storage tank 5f Tank hot water temperature sensor 6 Hot water outlet passage 7 Hot water supply passage 9 Circulation heating circuit 9d Circulation temperature sensor 10 Water supply passage 11 Hot water storage control section (control means)
19 Water supply temperature sensor 23 Hot water supply temperature sensor 25 Circulation pump (circulation means)
34 HP control unit 40 Ring pump 41 External heat source incoming water temperature sensor 42 External heat source hot water temperature sensor 43 Mixing valve incoming water temperature sensor 44 Outside air temperature sensor 50 Communication means

Claims (3)

An external heat source unit, a hot water storage unit including a hot water storage tank, a circulation heating circuit connecting the external heat source unit and the hot water storage tank, a circulation means provided in the circulation heating circuit, and a communication means between the two units. In the hot water storage and hot water supply apparatus provided with control means capable of controlling both units by communicating with the communication means,
The control means acquires the detected temperature of the temperature detection means provided in each of the two units, performs the freeze prevention operation based on a predetermined temperature condition, and when communication failure occurs in the communication means A hot water storage and hot water supply apparatus that performs the freeze prevention operation while relaxing the temperature condition.   The control means and the circulation means are provided in one of the external heat source unit and the hot water storage unit, and the freeze prevention operation is a hot water circulation operation performed by driving the circulation means. The hot water storage hot water supply apparatus according to 1.   The hot water storage hot water supply apparatus according to claim 1 or 2, wherein the external heat source unit is a heat pump, and the hot water storage unit includes a combustion type auxiliary heat source machine.