JP2017116180A - Heat pump water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump water heater enabling system efficiency to be improved by performing control to allow a heating operation to be performed by a heat pump heat source machine regardless of water volume enabling heat storage in a hot water storage tank after a fixed command definite time passes after issuance of a hot water filling operation command.SOLUTION: A heat pump water heater includes: a heat pump heat source machine; hot water storage tank for storing hot water; heat quantity detection means for detecting heat quantity in the hot water storage tank; a hot water supply passage for supplying hot water to a hot water supply destination; and a hot water filling passage branched from the hot water supply passage to fill hot water in a bathtub. Control means includes: heating operation prohibiting means for prohibiting a heating operation performed by the heat pump heat source machine when the heat quantity in the hot water storage tank detected by the heat quantity detection means is preset set heat quantity or more; and heating operation allowing means for allowing the heating operation performed by the heat pump heat source machine regardless of the heat quantity in the hot water storage tank after a fixed command definite time passes after issuance of a command when the command to perform a hot water filling operation to the bathtub is issued by operation means.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat pump hot water supply apparatus that permits and controls a heating operation by a heat pump heat source device regardless of a free capacity of a heat amount in a hot water storage tank after a predetermined command confirmation time has elapsed from a hot water filling operation command.

  Conventionally, heat pump hot water supply devices have been widely spread. Such a heat pump hot water supply apparatus includes a heat pump heat source device that heats hot water with a refrigerant, a hot water storage tank that stores heated hot water, a hot water circulation circuit that circulates hot water between the heat pump heat source device and the hot water storage tank, and the like. Hot water in the tank is circulated through a hot water circulation circuit and heated by a heat pump heat source device, and the heated hot water is returned to and stored in a hot water storage tank and supplied to a desired hot water supply destination such as a hot water tap or a bathtub.

  In the above heat pump hot water supply device, when the hot water storage tank is fully stored, the operation request of the heat pump heat source machine is not accepted, and when hot water is consumed by hot water supply and pouring, the hot water storage tank is not fully stored, that is, the hot water storage tank It is controlled to permit the heating operation request of the heat pump heat source unit on condition that the hot water in the inside is consumed and is no longer in a fully stored state.

  In the heat pump hot water supply apparatus of Patent Literature 1, when a bath hot water filling signal is received, a heat storage amount Q in the hot water storage tank is calculated based on temperature information from a thermistor provided in the hot water storage tank, and thereafter, after a predetermined time has elapsed, the same The heat storage amount Q1 in the hot water storage tank is calculated based on the temperature information from the thermistor, and if the reduced heat storage amount Q-Q1 is greater than the predetermined heat amount, it is determined that a large amount of heat is required for the hot water filling of the bath. Then, the operation of the heat pump device is controlled to continue until the hot water filling is completed.

Japanese Patent No. 4501815

  However, in the heat pump hot water supply device, even if the operation request of the heat pump heat source machine is permitted on condition that the hot water storage tank is no longer fully charged, the hot water storage tank has little heat capacity (water capacity that can store heat) The hot water storage tank becomes fully charged within a few minutes after the start of the heating operation with the heat pump heat source machine, and the heating operation of the heat pump heat source machine immediately stops, so that the system efficiency of the heat pump hot water supply device is reduced.

Therefore, heating operation control is generally adopted that permits the heating operation of the heat pump heat source machine on condition that the free capacity of the heat quantity in the hot water storage tank has reached a set value or more.
However, when the above heating operation control is adopted, when hot water filling to the bathtub is performed, the heating operation of the heat pump heat source machine is performed after the calorific capacity of the hot water storage tank becomes equal to or more than the set value. When a large amount of hot water supply is required for shower use immediately after pouring by hot water filling, there is a problem that hot water in the hot water storage tank is insufficient and the hot water runs out.

  An object of the present invention is to provide a heat pump water heater that improves the system efficiency by permitting the heating operation of the heat pump heat source machine regardless of the free capacity of the amount of heat in the hot water storage tank after the elapse of a fixed command determination time from the hot water operation command. Is to provide.

  The heat pump hot water supply apparatus according to claim 1 is a heat pump heat source device, a hot water storage tank for storing hot water, an auxiliary heat source device, a control means for controlling them, and an operation command to the control means according to a user's operation. A heat amount detecting means for detecting the amount of heat in the hot water storage tank, a hot water supply passage for supplying hot water to a hot water supply destination, a tank hot water connecting the upper end portion of the hot water storage tank and the hot water supply passage In the heat pump hot water supply apparatus including a passage and a pouring passage that branches from the hot water supply passage and fills the bathtub, the control means is configured so that the amount of heat in the hot water storage tank detected by the heat amount detection means is in advance. A heating operation prohibiting means for prohibiting a heating operation by the heat pump heat source device when the set heat quantity is equal to or greater than a set heat amount, and a hot water filling operation to the bathtub is commanded by the operating means. It is characterized in that a heating operation permission means for permitting the heating operation by the heat pump heat source unit regardless to the amount of heat of the hot water storage tank after a certain command settling time from the command when it is.

  According to the first aspect of the present invention, the control means is configured to prohibit the heating operation by the heat pump heat source device when the heat quantity in the hot water storage tank detected by the heat quantity detection means is equal to or greater than a preset set heat quantity. Since it has a prohibition means, if it is determined that the amount of heat in the hot water storage tank is greater than or equal to the set heat amount and is not in a state where heat can be stored substantially, the heating operation by the heat pump prohibition means is prohibited by the heating operation prohibition means. It is possible to improve a decrease in system efficiency caused by stopping immediately after starting operation.

  In addition, the control means permits a heating operation permission to allow a heating operation by the heat pump heat source device regardless of the amount of heat in the hot water storage tank after a certain command confirmation time has elapsed from the command when a hot water filling operation to the bathtub is commanded by the operation device. When the hot water filling operation is instructed, it is determined that the hot water filling operation will not be canceled if a predetermined command confirmation time has elapsed from the command, and the heating operation permission means Regardless of the available heat capacity, the heating operation by the heat pump heat source is permitted. For this reason, even if a large amount of hot water is required for shower use after filling the bathtub, hot water in the hot water storage tank can be avoided and system efficiency can be improved.

It is the schematic of the heat pump hot-water supply apparatus of this invention. It is a flowchart which shows the control which permits the operation | movement of a heat pump heat-source machine after fixed instruction | command fixed time progress from a hot water operation instruction | command.

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

First, a schematic configuration of the heat pump water heater 1 of the present invention will be described.
As shown in FIG. 1, the heat pump hot water supply apparatus 1 includes a hot water storage hot water supply unit 2 having an auxiliary heat source unit 4 and the like, and a heat pump heat source unit 3. The hot water storage and hot water supply unit 2 branches from a hot water storage tank 5 for storing hot water, a hot water supply passage 6 for supplying hot water to a hot water supply destination, a tank hot water supply passage 7 connecting the upper end of the hot water storage tank 5 and the hot water supply passage 6, and the hot water supply passage 6. Then, a pouring passage 8 for filling the bathtub with hot water, a heating circulation circuit 9 for connecting the hot water in the hot water storage tank 5 so as to be heated by the heat pump heat source device 3 and stored in the hot water storage tank 5, and water in the hot water storage tank 5 Water supply passage 10, a control unit (corresponding to control means) 11 for performing various controls, a bath recuperation heat exchanger 12 for heating hot water in the bathtub 29, a bath recuperation circuit 13, and the like. Yes.

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

  A circulation pump 25 is provided in the middle of the heating circulation passage 9a, and a circulation temperature sensor 9d is provided in the middle of the heating circulation passage 9b. A circulation switching valve 15 is provided at a connection point between the heating circulation passage portion 9a and the bypass passage portion 9c, and the circulation passage valve 15 is switched to switch between the bypass passage side and the hot water storage tank side. When the circulation switching valve 15 is switched to the bypass passage side, the hot water heated by the heat pump heat source unit 3 is sent to the heat pump heat source unit 3 so as to be reheated.

  On the outer periphery of the hot water storage tank 5, a plurality of temperature sensors 5a to 5d (corresponding to heat amount detection means) are provided in order from the bottom in order to detect the temperature of the stored hot water. The number of temperature sensors provided in the hot water storage tank 5 can be changed as appropriate according to the specifications of the heat pump hot water supply apparatus 1. Moreover, in order to prevent the temperature of the stored hot water from falling, the periphery of the hot water storage tank 5 is covered with a heat insulating material (not shown).

  The tank outlet passage 7 supplies hot water stored in the hot water storage tank 5 to the hot water supply passage 6. The upstream end is connected to the upper end portion of the hot water storage tank 5, and the downstream end is connected to the hot water supply passage 6 via the mixing valve 16. It is connected. An upstream auxiliary heating passage portion 14 a branched from the middle of the tank hot water passage 7 is connected to the three-way valve 17 and includes an auxiliary heat source unit passage 14 connected to the hot water supply passage 6 via the auxiliary heat source unit 4.

  The pouring passage 8 that branches off from the hot water supply passage 6 and fills the bathtub 29 is provided with an open / close valve 31 connected to the bath passage passage portion 13a, and the downstream end of the pouring passage 8 is connected to the bath passage passage portion 13a. It is connected. In order to supply hot water at a temperature set by the operating device 40 to the bathtub 29, hot water flowing out from the upper part of the hot water storage tank 5 passes through the tank outlet passage 7 and the hot water supply passage 6 and is mixed with clean water in the mixing valve 16. As a result, the hot water flows into the pouring passage 8 and is supplied to the bathtub 29 via the on-off valve 31 and the bath passage portion 13a.

  The water supply passage 10 supplies low-temperature clean water from a clean water source to the hot water storage tank 5 and the like, and has an upstream end connected to the clean water source and a downstream end connected to the lower end of the hot water storage tank 5. A water supply bypass passage 18 is branched from the water supply passage 10 and connected to the mixing valve 16. A water supply temperature sensor 19 and a check valve 20 are provided in the water supply passage 10, and a check valve 21 is provided in the water supply bypass passage 18. A high temperature hot water avoidance passage 22 branched from the water supply bypass passage 18 and connected to the hot water supply passage 6 is provided so as to avoid high temperature hot water.

  The mixing valve 16 supplies hot water at a temperature (hot water supply set temperature) set by the user via the operation device 40 from the hot water supply passage 6 or supplies hot water at a hot water supply set temperature to the bathtub 29. The mixing ratio of the low temperature clean water supplied from 18 and the high temperature hot water supplied from the tank outlet passage 7 is adjusted. Hot water mixed with clean water and adjusted to a hot water supply set temperature is supplied from the hot water supply passage 6 to the hot water tap or supplied from the hot water supply passage 8 to the bathtub 29. A hot water supply temperature sensor 23 and a hot water supply flow rate sensor 24 are provided in the hot water supply passage 6 to detect the hot water supply temperature and the hot water supply flow rate.

  The bath remedy heat exchanger 12 heats hot water in the bathtub 29 flowing through the bath remedy circuit 13 by heat exchange with hot water flowing through the heat exchanger forward passage portion 32a branched from the downstream auxiliary heating passage portion 14c. The downstream end of the heat exchanger return passage portion 32b on the outlet side of the bath recuperation heat exchanger 12 is connected to the three-way valve 17, and the branch passage portion 10a branched from the water supply passage 10 supplies water to the heat exchanger return passage portion 32b. Connected as possible. The heat exchanger return passage 32b is provided with an on-off valve 33, which is closed so that hot water does not flow into the bath chase heat exchanger 12 except during the bath chase operation.

  The bath remedy circuit 13 circulates hot water in the bathtub 29 and heats it in the bath remedy heat exchanger 12, and a bath going-out passage section that sends hot water heated from the bath remedy heat exchanger 12 to the bathtub 29. 13a and a bath return passage portion 13b provided with a remedy pump 30 for sending hot water from the bathtub 29 to the bath remedy heat exchanger 12.

Next, the heat pump heat source unit 3 will be described.
The heat pump heat source unit 3 is controlled by the control unit 11 via the auxiliary control unit 34, and the compressor 35, the condensation heat exchanger 36, the expansion valve 37, and the evaporating heat exchanger 38 are connected by a refrigerant pipe 39 to connect the heat pump circuit. This is a heat pump hot water supply apparatus that heats hot and cold water using the refrigerant enclosed in the refrigerant pipe 39 and the heat of the outside air.

Next, the control unit 11 will be described.
The control unit 11 acquires the temperature and flow rate of each part by the hot water storage temperature sensors 5a to 5d, the circulation temperature sensor 9d, the feed water temperature sensor 19, the hot water supply temperature sensor 23, the hot water supply flow rate sensor 24, etc. The circulation switching valve 15, the mixing valve 16, the circulation pump 25, etc. provided at 6 etc. are operated, and the heat pump heat source unit 3 is heated to perform hot water storage operation and hot water supply so that hot water filling or hot water supply can be performed at the hot water supply set temperature. Controls driving and the like.

Next, hot water storage operation will be described.
The control unit 11 operates the heat pump heat source unit 3, switches the circulation switching valve 15 to the hot water storage tank side, drives the circulation pump 25, and supplies low-temperature hot water from the lower part of the hot water storage tank 5 to the heat pump heat source unit 3. Hot water having a set temperature of hot water heated by the heat source device 3 is stored in the upper part of the hot water storage tank 5. By continuing the hot water storage operation, the hot water layer of the hot water set temperature stored in the upper part of the hot water storage tank 5 expands downward, and the low temperature hot water layer shrinks. The control unit 11 can detect the amount of hot hot water stored in the hot water storage tank 5 and the amount of heat in the hot water storage tank 5 based on the temperatures detected by the plurality of temperature sensors 5 a to 5 d provided in the hot water storage tank 5.

Next, hot water filling operation will be described.
When the user sets the hot water supply temperature from the operation device 40 and turns on the automatic bath switch, the hot water supply set temperature and the bath hot water filling instruction are transmitted to the control unit 11. Low temperature clean water flows into the lower end portion of the hot water storage tank 5 through the water supply passage 10, and hot water stored from the upper end portion of the hot water storage tank 5 flows into the mixing valve 16 through the tank hot water discharge passage 7 by this water supply pressure. To do. The control unit 11 adjusts the mixing valve 16 to supply hot water at a hot water supply set temperature from the pouring passage 8 to the bathtub 29 via the hot water supply passage 6.

  When the hot water filling is continued, the low temperature hot water layer below the hot water storage tank 5 expands upward, and the high temperature hot water layer shrinks. At this time, the control unit 11 can detect the amount of heat in the hot water storage tank 5 based on the temperatures detected by the plurality of temperature sensors 5 a to 5 d provided in the hot water storage tank 5.

  When 5 seconds have passed since the bath automatic switch was turned on, the control unit 11 operates the circulation pump 25 to permit the heating operation of the heat pump heat source unit 3 while maintaining the hot water filling, and the hot water storage tank 5 The low-temperature hot water at the lower part of the water is sent from the heating circulation passage portion 9a to the heat pump heat source unit 3, and the heat circulation with the refrigerant sealed in the refrigerant pipe 39 in the condensing heat exchanger 36 makes the low-temperature hot water hot water. It supplies to the upper end part of the hot water storage tank 5 from the heat pump heat source machine 3 via the channel | path part 9b.

  At this time, control for permitting operation by the heat pump heat source unit 3 in the control unit 11 will be described based on the flowchart of FIG. In the flowchart, Si (i = 1, 2,...) Represents each step.

  In S1, various detection signals such as the temperature and flow rate of each part are read by the operating device 40, the hot water storage temperature sensors 5a to 5d, the circulation temperature sensor 9d, the feed water temperature sensor 19, the hot water supply temperature sensor 23, the hot water supply flow rate sensor 24, and the like. The amount of heat in the hot water storage tank 5 is calculated based on detection signals from the hot water storage temperature sensors 5a to 5d.

  Next, in S2, it is determined whether the heating operation in the heat pump heat source unit 3 is requested. If the determination is Yes, the process proceeds to S3, and if the determination is No, the process returns.

  Next, in S3, it is determined whether 5 seconds or more have elapsed since the automatic bath switch was turned on. If the determination is Yes, the process proceeds to S5, and the operation of the heat pump heat source unit 3 is permitted. If the determination is No, the process proceeds to S4. The “5 seconds” corresponds to a “certain command fixed time” in which the bath automatic switch ON command is fixed.

  The fact that 5 seconds or more have passed since the bath automatic switch was turned on means that the bath automatic switch is not canceled and a large amount of hot water is consumed for filling the bathtub 29 thereafter, so the heating operation of the heat pump heat source unit 3 is avoided. Is not expected. Moreover, it is predicted that the hot water in the hot water storage tank 5 will be insufficient if the shower is used immediately after the hot water filling to the bathtub 29 is completed.

Here, when the heating operation of the heat pump heat source unit 3 is started after the hot water filling is started until the heat storage capacity of the hot water storage tank 5 reaches a predetermined amount (for example, 500 kcal), a hot water supply request such as shower use is required. There is a risk of running out of hot water.
Therefore, when the determination in S3 is Yes, the operation of the heat pump heat source unit 3 is permitted in S5 (corresponding to a heating operation permission unit), and the heating operation of the heat pump heat source unit 3 is started.

  If the determination in S3 is No, the process proceeds to S4. In S4, whether or not the free capacity of the heat amount in the hot water storage tank 5 is a predetermined amount (for example, 500 kcal) or more (that is, the heat amount in the hot water storage tank 5 is set in advance). It is determined whether or not it is less than the set heat amount. When the determination is Yes, the process proceeds to S5, and the operation of the heat pump heat source unit 3 is permitted in S5, and the heating operation of the heat pump heat source unit 3 is started. If the determination in S4 is No, the process proceeds to S6, the heating operation of the heat pump heat source unit 3 is prohibited, and the process returns to S3 (corresponding to the heating operation prohibiting means).

  That is, when hot water having a temperature equal to or higher than the set heat amount is not stored in the hot water storage tank 5 (S4; Yes), a heating operation is requested from the control unit 11 to the auxiliary control unit 34 on the heat pump heat source unit 3 side. When hot water having a temperature equal to or higher than the set amount of heat is stored in the hot water storage tank 5 (S4; No), even if the hot water supply operation is started by the heat pump heat source unit 3, the hot water storage tank 5 immediately becomes full and the heat pump Since the heat source unit 3 stops, the hot water supply operation in the heat pump heat source unit 3 is prohibited (S6).

Here, calculation of the free capacity of the heat quantity in the hot water storage tank 5 will be briefly described.
If the capacity in the hot water storage tank 5 is Vo, and the hot water temperature in the fully stored state is To ° C,
The amount of heat Qm in the fully stored state can be calculated using Vo and To as parameters.
On the other hand, assuming that the capacity corresponding to the hot water storage temperature sensors 5a to 5d is Va to Vd and the detected temperatures of the temperature sensors 5a to 5d are Ta to Td, the total heat quantity Qt in the hot water storage tank 5 is Va to Vd and Ta to Td. The free heat capacity ΔQ can be calculated using ΔQ = (Qm−Qt)
Can be calculated as The temperature sensors 5a to 5d and the control unit 11 correspond to a heat amount detection unit.

  Here, the heating capacity of the heat pump heat source apparatus 3 of the present embodiment is 2.2 kW, and a hot water supply operation with a heat quantity of 1892 kcal can be performed in one hour. For this reason, if the free capacity ΔQ of the amount of heat in the hot water storage tank 5 is 500 kcal or more, the heat pump heat source unit 3 can be continuously supplied with hot water for at least 15 minutes, and immediately after the heat pump heat source unit 3 is operated. It is possible to avoid an inefficient operation of stopping the vehicle.

Next, the operation and effect of the heat pump hot water supply apparatus 1 of the present invention will be described.
The control unit 11 includes a heating operation prohibiting unit that prohibits the heating operation by the heat pump heat source unit 3 when the amount of heat in the hot water storage tank 5 detected by the plurality of temperature sensors 5a to 5d is equal to or greater than a preset set amount of heat. Therefore, when it is determined that the amount of heat in the hot water storage tank 5 is greater than the set amount of heat and is not in a state where heat can be stored, the heating operation by the heat pump heat source device 3 is prohibited by the heating operation prohibiting means, and the heat pump heat source device 3 It is possible to improve the decrease in system efficiency caused by stopping immediately after starting operation.

  In addition, when the operation unit 40 commands the hot water filling operation to the bathtub 29, the control unit 11 is a heat pump heat source regardless of the amount of heat in the hot water storage tank after a predetermined command confirmation time (for example, 5 seconds) has elapsed since the command. Since the heating operation permission means for permitting the heating operation by the machine 3 is provided, when the filling operation is instructed, the filling operation is canceled if a predetermined command determination time of 5 seconds or more elapses from the instruction. It is determined that there is no heat, and the heating operation by the heat pump heat source device 3 is permitted by the heating operation permission means regardless of the free capacity of the heat amount in the hot water storage tank 5. For this reason, even if a large amount of hot water is required for shower use after filling the bathtub 29, it is possible to avoid running out of hot water in the hot water storage tank 5 and operation by the auxiliary heat source unit 4 and improve system efficiency. it can.

  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.

DESCRIPTION OF SYMBOLS 1 Heat pump hot water supply apparatus 2 Hot water storage hot water supply unit 3 Heat pump heat source machine 4 Auxiliary heat source machine 5 Hot water storage tank 5a-d Temperature sensor (heat quantity detection means)
6 Hot water supply passage 7 Tank discharge passage 8 Pouring passage 11 Control unit (control means, heat quantity detection means)

Claims (1)

A heat pump heat source device, a hot water storage tank for storing hot water, an auxiliary heat source device, a control means for controlling these, and an operating device for transmitting an operation command to the control means in accordance with a user operation, A quantity of heat detecting means for detecting the amount of heat in the hot water storage tank, a hot water supply passage for supplying hot water to a hot water supply destination, a tank hot water passage connecting the upper end of the hot water storage tank and the hot water supply passage, and a branch from the hot water supply passage. In a heat pump hot water supply device equipped with a pouring passage for filling the bathtub with hot water,
The control means, when the amount of heat in the hot water storage tank detected by the heat amount detection means is greater than or equal to a preset set amount of heat, heating operation prohibiting means for prohibiting the heating operation by the heat pump heat source unit, A heating operation permission means for permitting the heating operation by the heat pump heat source device regardless of the amount of heat in the hot water storage tank after the elapse of a certain command determination time from the command when a hot water filling operation to the bathtub is commanded by the operation means. A heat pump hot water supply device characterized by that.