JP6182087B2 - Heat pump hot water storage system - Google Patents

Description

  The present invention relates to a heat pump hot water storage type hot water supply apparatus provided with a bath heat exchanger that heats bathtub water using hot water in a hot water storage tank as a heat source.

  Conventionally, in this type of heat pump hot water storage type hot water supply device, a hot water storage tank for storing hot water, a bath heat exchanger for heating bath water using the hot water in the hot water storage tank as a heat source, and hot water from the lower part of the hot water storage tank to the upper part of the hot water storage tank. A heat pump heating means that heats the hot water in the hot water storage tank provided in the middle of the heating circulation circuit that circulates, and a heat pump heating means when the amount of hot water stored in the hot water storage tank rises to a predetermined level during the daytime And a reheating control means for performing a reheating operation to reheat the bath water with the hot water in the hot water storage tank boiled at night. If there was a track record of reheating, it was trying to avoid a shortage of heat when chasing the remaining hot water by raising the boiling temperature of hot water stored at night.

JP 2012-177534 A

  However, in this conventional one, the heating efficiency of the heat pump type heating means is deteriorated by raising the boiling temperature, and the amount of natural heat radiation from the hot water storage tank is increased, and the overall operation efficiency is lowered. There was a problem.

  Therefore, an object of the present invention is to improve the overall operation efficiency while avoiding a shortage of heat when the remaining hot water is replenished.

In order to achieve the above object, the present invention provides a hot water storage tank for storing hot water, a water supply pipe connected to the lower part of the hot water storage tank, a hot water pipe connected to the upper part of the hot water storage tank, and hot water in the hot water storage tank. A bath heat exchanger for heating the bath water, a heating circulation circuit for circulating hot water from the lower part of the hot water storage tank to the upper part of the hot water storage tank, and a heat pump provided in the middle of the heating circulation circuit for heating the hot water in the hot water storage tank If it is determined that the heating operation of the water heater and the heating operation of the bathtub water is replenishment of remaining hot water, and if it is determined that the remaining hot water is replenished, the remaining hot water replenishment record is stored and stored for a predetermined period of time. If no remaining hot water replenishment is performed, the fact that there is no remaining hot water replenishment record is stored, and the amount of hot water stored in the hot water storage tank satisfies a predetermined increase start condition in a specific time zone. And control means for performing additional boiling operation by operating the heat pump heating means and detecting that the said control means, the temperature of the reheating before the start of the temperature of the bath water with a preset bath set temperature If the difference is more than a certain value, it is determined that the remaining hot water has been reheated. The start condition was changed.

  The boiling start condition is stored on the condition that a specific hot water temperature sensor of a plurality of hot water temperature sensors provided on the side surface of the hot water tank is below a predetermined temperature, and that there is a remaining hot water replenishment record. If the hot water storage temperature sensor provided at a lower position than the case where no record is stored is used as the specific hot water storage temperature sensor, the boiling increase start condition is changed in a direction in which boiling increases easily. I made it.

  The boiling start condition is stored on the condition that a specific hot water temperature sensor of a plurality of hot water temperature sensors provided on the side surface of the hot water tank is below a predetermined temperature, and that there is a remaining hot water replenishment record. If it is, the condition for starting the boiling increase is changed in a direction in which the boiling starts more easily by setting a predetermined temperature higher than that in the case where no record is stored.

  According to the present invention, it is possible to always secure a large amount of heat in the hot water storage tank, to avoid a shortage of heat when the remaining hot water is replenished without increasing the boiling temperature, and to improve overall operation efficiency. be able to.

Schematic configuration diagram of one embodiment of the present invention Flow chart for explaining the operation of the same embodiment

Next, a heat pump hot water storage type hot water supply apparatus according to an embodiment of the present invention will be described with reference to the drawings.
1 is a hot water storage tank unit, 2 is a heat pump unit constituting a heat pump type heating means, 3 is a hot water tap, 4 is a bathtub, and 5 is a remote controller.

<Hot water storage tank unit 1>
6 is a stainless steel hot water storage tank for storing hot water, 7 is a water supply pipe for supplying water to the bottom of the hot water storage tank 6, 8 is a hot water discharge pipe for discharging hot water from the top of the hot water storage tank 6, and 9 is a water supply bypass pipe branched from the water supply pipe 7. 10 is a mixing valve that mixes hot water from the hot water discharge pipe 8 and water from the water supply bypass pipe 9, 11 is a hot water supply pipe that guides the hot water mixed by the mixing valve 10 to the hot water tap 3, and 12 is hot water that flows through the hot water supply pipe 11. A hot water supply flow sensor for detecting the flow rate of the hot water, 13 is a hot water temperature sensor for detecting the temperature of the hot water flowing through the hot water supply 11, 14 is a pressure reducing valve provided in the middle of the water supply pipe 7, and 15 is connected to the upper part of the hot water storage tank 6. Thus, the overpressure relief valve is used to relieve overpressure caused by the expansion of the hot water in the hot water storage tank 6.

  16 is a bath heat exchanger made of a stainless steel tube wound in a serpentine shape and disposed at the upper part of the hot water storage tank 6, and 17 is a bath circulation that connects the bathtub 4 and the bath heat exchanger 16 so that the bath water can circulate. The circuit, 18 is a bath circulation pump that circulates the bath water, 19 is a bath bypass pipe that bypasses the bath circulation circuit 17, and 20 is provided at a branch point or a junction with the bath bypass pipe 19 of the bath circulation circuit 17, Bath three-way valve that switches between circulating or bypassing the bath heat exchanger 16, 21 is a bath temperature sensor that detects the temperature of the bath water, 22 is a running water switch that detects that a flow rate of a certain amount or more has flown, 23 Is a water level sensor that detects the water level in the bathtub 14 by detecting pressure.

  Reference numeral 24 denotes a hot water pipe that branches from the hot water supply pipe 11 and communicates with the bath circulation circuit 17, 25 denotes a hot water on / off valve that opens and closes the flow path of the hot water pipe 24, and 26 detects the flow rate of hot water flowing through the hot water pipe 24. This is a hot water filling flow sensor.

  A heating circulation circuit 27 connects the bottom of the hot water storage tank 6, the heat pump unit 2, and the upper part of the hot water storage tank 6 so that hot water can circulate. A temperature sensor 29 is supplied with detection values of a hot water flow rate sensor 12, a hot water temperature sensor 13, a bath temperature sensor 21, a running water switch 22, a water level sensor 23, and a hot water storage temperature sensor 28, and the mixing valve 10, the bath circulation pump 18, and the bath three-way. The hot water storage control means controls the operation of the valve 20 and the hot water on / off valve 25 and is connected to the heat pump unit 2 and the remote controller 5 so that necessary information can be transmitted and received. Here, the hot water storage control means 29 has a logic circuit such as an MPU and controls the operation according to a program stored in advance while referring to the memory.

<Heat pump unit 2>
30 is a compressor that compresses the refrigerant, 31 is a water heat exchanger in which the refrigerant from the compressor 30 circulates on the primary side and the secondary side is connected to the heating circuit 27, and 32 is a refrigerant that has flowed out of the water heat exchanger 31. A decompression expansion valve 33 for decompressing and expanding, an evaporator 33 for evaporating the refrigerant which has been decompressed and expanded by the decompression expansion valve 32 to a low temperature and a low pressure, 34 is a compressor 30, a hydrothermal exchanger 31, a decompression expansion valve 32 and an evaporator Reference numeral 33 denotes a refrigerant circulation circuit that connects the refrigerant in a circulating manner, and reference numeral 35 denotes a blower that blows air as a heat source to the evaporator 33.

  The refrigerant circulation circuit 34 uses an HFC refrigerant such as R410A or a refrigerant that operates at a lower pressure than a CO2 refrigerant such as an R32 refrigerant, so that the feed water can be efficiently heated to a temperature of about 65 ° C. In addition, it is good also as a structure which can be heated to the temperature of about 90 degreeC using the CO2 refrigerant | coolant which operate | moves at a high pressure.

  36 is a heating circulation pump provided in the heating circulation circuit 27 on the inlet side of the water heat exchanger 31, 37 is a discharge temperature sensor for detecting the temperature of the refrigerant discharged from the compressor 30, and 38 flows into the water heat exchanger 31. An incoming water temperature sensor for detecting the temperature of water to be heated, 39 is a boiling temperature sensor for detecting the temperature of hot water heated by the water heat exchanger 31, 40 is an outdoor air temperature sensor for detecting the outdoor air temperature, and 41 is a discharge temperature sensor 37. The detection values of the incoming water temperature sensor 38, the boiling temperature sensor 39, and the outside air temperature sensor 40 are input to control the operations of the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36, and the hot water storage tank unit 1 It is a heating control means connected to the hot water storage control means 29 so that necessary information can be transmitted and received. Here, the heating control means 41 has a logic circuit such as an MPU and controls the operation according to a program stored in advance while referring to the memory.

<Remote controller 5>
42 is a dot-matrix liquid crystal display unit that displays various information relating to hot water supply (hot water set temperature, bath set temperature, amount of remaining hot water in the tank, hot water supply device operating status, date and time, etc.), 43 is a hot water set temperature, bath set temperature, A cross key for setting a hot water filling set amount, etc., 44 is a bath automatic key for performing automatic bath operation, 45 is a reheating key for performing bath water reheating operation, and 46 is a display unit 42 for indicating the operating state of the hot water supply device. The remote control means connected to the hot water storage unit 29 of the hot water tank unit 1 so as to be able to transmit and receive necessary information is controlled to display on the display unit 42 and information corresponding to the operation of each operation key. is there. Here, the remote control means 46 has a logic circuit such as an MPU and controls the operation according to a program stored in advance while referring to the memory.

<Hot-water supply operation>
Next, operation during hot water supply will be described. When the hot-water tap 3 is opened, water from the water supply pipe 7 flows into the bottom of the hot water storage tank 6, and hot water at the top of the hot water storage tank 6 flows out from the hot water supply pipe 8, and from the water supply bypass pipe 9 by the mixing valve 10. It is mixed with water and flows out from the hot water supply pipe 11. When the hot water supply flow sensor 12 detects the start of hot water supply, the hot water storage control means 29 feedback-controls the opening degree of the mixing valve 10 so that the hot water temperature detected by the hot water temperature sensor 13 coincides with the set hot water temperature. Hot water supply at a hot water supply set temperature is performed until the stopper 3 is closed.

  At this time, the hot water storage control means 29 calculates the hot water amount (heat amount) consumed for the hot water supply from the hot water supply flow rate, the hot water supply temperature, and the hot water supply temperature, and accumulates and stores the hot water supply load for the day. And the hot water storage control means 29 memorize | stores the integrated hot water supply load for several days (here 7 days) for every day (here 7 days).

<Bath operation>
Next, a bath operation when the bath automatic key 44 of the remote controller 5 is operated will be described. When the bath automatic key 44 is operated, the hot water storage control means 29 drives the bath circulation pump 18 with the bath three-way valve 20 on the side of the bath bypass pipe 19 and determines whether or not the running water switch 22 detects running water. The presence or absence of remaining hot water in the bathtub 4 is detected.

  When it is confirmed that the running water switch 22 is not turned ON, the hot water on / off valve 25 is opened and the mixing valve 10 is controlled so as to reach the bath set temperature with no remaining hot water in the bathtub 4, and a hot water set amount of hot water is set. Start tensioning.

  When the hot water filling flow sensor 26 counts the hot water filling set amount, the hot water on / off valve 25 is closed, and then the bath circulation pump 18 is driven to confirm that there is running water with the running water switch 22, and the bath temperature sensor 21 When the temperature of the bath water to be detected is lower than the bath set temperature, the bath three-way valve 20 is switched to the bath heat exchanger 16 side to perform the bath water reheating operation, and the bath water temperature rises to the bath set temperature. The remote controller 5 notifies the completion of hot water filling.

  At this time, the hot water storage control means 29 calculates the hot water amount (heat amount) consumed by the hot water filling from the hot water supply flow rate, the hot water supply temperature, and the hot water supply temperature, and accumulates and stores the hot water supply load for the day.

  On the other hand, when the bath automatic key 44 is operated, if there is remaining hot water of the previous day in the bathtub 4 or the reheating key 45 is operated, the flowing water switch 22 is used to check whether there is remaining hot water. Is detected, the bath three-way valve 20 is switched to the bath heat exchanger 16 side due to the remaining hot water, and the bath water reheating operation is performed. The bath water temperature detected by the bath temperature sensor 21 becomes the bath set temperature. When it reaches, the driving of the bath circulation pump 18 is stopped, and the completion of the chasing is notified by the remote controller 5.

  At this time, when the hot water storage control means 29 detects the temperature of the remaining hot water and the temperature difference from the bath set temperature is a certain value (for example, 5 ° C.) or more, the hot water storage control means 29 determines that the low temperature remaining hot water is replenished. I remember to track down the remaining hot water.

  Then, the hot water storage control means 29 determines whether or not the remaining hot water is replenished every time the bath water is replenished. If there is no remaining hot water renewal record for a predetermined period (for example, 3 days), the remaining hot water renewal is performed. It remembers that there was no whispering record.

<Boiling operation>
Next, the boiling operation will be described.
When the start time of the midnight time zone comes, the hot water storage control means 29 predicts the hot water supply load on the next day from the stored accumulated hot water supply loads for the past plural days, and calculates the target hot water storage amount. The current hot water storage amount of the hot water storage tank 6 detected by the hot water storage temperature sensor 28 is subtracted from the target hot water storage amount, and the boiling target amount to be heated during the midnight time zone is calculated. Boiling from the target boiling amount, a predetermined boiling target temperature, the feed water temperature detected by the hot water storage temperature sensor 28 at the bottom of the hot water storage tank 6, and the heating capacity of the heat pump unit 2 stored in advance as numerical values. Calculate the required time. The boiling start time is calculated by tracing the required boiling time from the end time of the midnight time zone.

  When the boiling start time arrives, the hot water storage control means 29 outputs an instruction to start the boiling operation to the heating control means 41, and the heating control means 41 has the temperature detected by the boiling temperature sensor 39 boiling. The compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36 are driven so as to coincide with the target heating temperature, and the boiling operation by the heat pump cycle is started.

  When the hot water storage temperature sensor 28 at the lowermost part of the hot water storage tank 6 detects a predetermined boiling end temperature or higher, it is determined that the boiling has ended, and the hot water storage control means 29 issues an instruction to stop the boiling operation to the heating control means 41. The heating control means 41 stops the heating operation by the heat pump cycle by stopping the driving of the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36. The boiling operation is stopped when the end time of the midnight time zone comes before the boiling is completed.

<Boiling operation>
Next, the boiling increase operation will be described based on the flowchart of FIG.
When the end time of the midnight time zone, which is the start time of a specific time zone, is reached, the hot water storage control means 29 confirms the current hot water storage amount detected by the hot water temperature sensor 28 (step S1), and according to the hot water storage amount and the hot water supply load. Subtracted from the target hot water storage volume calculated in this step to calculate the shortage, and from this shortage, the boiling target temperature, the feed water temperature, and the heating capacity, the time required to boil the shortage in the daytime period (Predicted boiling increase time) is calculated (step S2).

  In subsequent step S3, the hot water storage control means 29 confirms whether or not there is a remaining hot water replenishment record, and if a remaining hot water renewal record is stored, the process proceeds to step S4 and performs a boiling increase operation. If the start condition is a predetermined boiling start condition 1, and if there is no remaining hot water replenishment record, the process proceeds to step S5, and the condition for starting the boiling increase operation is set as a predetermined start condition. 2.

  Here, the boiling start condition 1 is that the fourth hot water storage temperature sensor 28 below the hot water storage tank 6 is below 50 ° C., and the boiling start condition 2 is that of the hot water storage tank 6. When the temperature of the third hot water storage temperature sensor 28 from below is lower than 50 ° C., it is a condition for starting the heating operation. In the heating start condition 1, the heating starts when the amount of hot water discharged from the hot water storage tank 6 is smaller. Therefore, it is set as a condition that it is easier to start boiling up than in boiling starting condition 2.

  Next, in step S6, it is confirmed whether or not there is a predicted boiling time. If there is a predicted boiling time, the process proceeds to step S7 with Yes, and the boiling start condition determined in step S4 or step S5 is set. Monitor whether it is true.

  When the amount of heat in the hot water storage tank 6 is consumed by hot water supply or bath operation and the boiling start condition is satisfied (Yes in step S7), the hot water storage control means 29 outputs an instruction to start the boiling increase operation to the heating control means 41. Then, the heating control means 41 drives the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36 so that the temperature detected by the boiling temperature sensor 39 coincides with the boiling target temperature, and the heat pump cycle. The boiling increase operation is started (step S8). At this time, the hot water storage control means 29 measures the operating time of the reheating operation and subtracts it from the predicted reheating time.

  Then, the hot water storage control means 29 monitors whether or not the boiling increase stop condition is established by the boiling increase operation (step S9). When the boiling increase stop condition is satisfied, the hot water storage control means 29 issues an instruction to stop the boiling increase operation. Output to the heating control means 41, and the heating control means 41 stops driving the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36, and stops the heating operation by the heat pump cycle (step S10). .

  Here, the boiling stop condition is that the hot water storage temperature sensor 28 at the bottom of the hot water storage tank 6 is 50 ° C. or higher, the remaining time of the predicted boiling time is 0, or the end time of a specific time zone. One of the conditions is that the start time of the midnight time zone is satisfied.

  After stopping the boiling increase operation, the process returns to step S6 to check whether or not there is a remaining time for the predicted boiling increase time. If there is a predicted boiling increase time, the process proceeds to step S7 with Yes, When the operation is performed and the remaining time of the estimated boiling time is 0, the process proceeds to step S11 with No, and the condition for starting the boiling increase operation is set as the boiling start condition 3.

  Here, the boiling start condition 3 is a condition for securing a minimum amount of hot water stored in order to prevent the hot water in the hot water storage tank 6 from becoming empty. Here, the hot water storage temperature sensor 28 at the top of the hot water storage tank 6 is used. The temperature is lower than 50 ° C. as a condition for starting the boiling operation, and is a condition that makes it difficult to start boiling than the above-described boiling start conditions 1 and 2.

  After the boiling increase start condition 3 is set, when the boiling increase start condition 3 is satisfied (Yes in step S7), the hot water storage control means 29 outputs an instruction to start the boiling increase operation to the heating control means 41, The heating control means 41 drives the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36 so that the temperature detected by the boiling temperature sensor 39 coincides with the boiling target temperature. An additional operation is started (step S8).

  Then, the hot water storage control means 29 monitors whether or not the boiling increase stop condition is established by the boiling increase operation (step S9). When the boiling increase stop condition is satisfied, the hot water storage control means 29 issues an instruction to stop the boiling increase operation. Output to the heating control means 41, and the heating control means 41 stops driving the compressor 30, the decompression expansion valve 32, the blower 35, and the heating circulation pump 36, and stops the heating operation by the heat pump cycle (step S10). .

  Here, when the boiling start condition 3 is set as the boiling stop condition, the fact that the second hot water storage temperature sensor 28 from the top of the hot water storage tank 6 is 50 ° C. or higher is used as the boiling stop condition. We try to secure the minimum amount of hot water storage just to avoid the situation where can not be used.

  As described above, when there is a record of the remaining hot water replenishment record, the hot water storage tank 6 is changed by changing the boiling start condition in a direction in which it is easier to start boiling than when the record of no record is stored. A large amount of heat can be secured in the interior at all times, and it is possible to avoid a shortage of heat when the remaining hot water is reheated without raising the boiling target temperature, and the remaining hot water is reheated without raising the boiling target temperature. Therefore, the amount of natural heat released from the hot water storage tank 6 is reduced, and further, the heating efficiency of the heat pump cycle is not lowered, so that the overall operation efficiency can be improved.

  On the other hand, when the remaining hot water replenishment record is not stored, the boiling start condition is changed in a direction that makes it difficult to start boiling compared to the case of storing the actual record. The time lag until it is actually consumed for hot water supply or the like is reduced, and the wasteful natural heat radiation from the hot water storage tank 6 can be reduced.

  The heating start condition is not limited to the above example. For example, among the plurality of hot water storage temperature sensors 28, the hot water storage temperature sensor 28 at a predetermined position (here, the third hot water storage temperature sensor 28 from the top of the hot water storage tank 6). ) Is equal to or lower than the predetermined temperature, and when the remaining hot water repurchase record is stored, the predetermined temperature is set to 55 ° C., and when no record is stored, the predetermined temperature is set to 50 ° C. In the case where there is a record of hot water boiling performance, the boiling start condition may be changed in a direction in which it is easy to start boiling by setting a predetermined temperature higher than when there is no performance.

  Further, the present invention is not limited to the above-described embodiment, and various modifications can be made without changing the gist of the invention. For example, a bath heat exchanger 16 is provided in the hot water storage tank 6. Although it is set as a form, it is not limited to this, The bath heat exchanger is provided in the exterior of the hot water storage tank 6, and the hot water in the hot water storage tank 6 circulates as a heat source for heating bath water to the primary side of the bath heat exchanger. It is good also as such a structure.

2 Heat pump unit (heat pump heating means)
6 Hot water storage tank 7 Water supply pipe 8 Hot water discharge pipe 16 Bath heat exchanger 27 Heating circulation circuit 28 Hot water storage temperature sensor 29 Hot water storage control means

Claims (3)

A hot water storage tank for storing hot water, a water supply pipe connected to the lower part of the hot water storage tank, a hot water pipe connected to the upper part of the hot water storage tank, and a bath heat exchanger for heating the bath water using the hot water in the hot water storage tank as a heat source A heating circuit that circulates hot water from the lower part of the hot water storage tank to the upper part of the hot water tank, a heat pump heating means that is provided in the middle of the heating circuit and heats the hot water in the hot water tank, and heating operation of the bath water When it is determined whether or not the remaining hot water is replenished, and when it is determined that the remaining hot water is replenished, the remaining hot water replenishment record is stored, and the remaining hot water is not replenished for a predetermined period of time. In addition, when there is no remaining hot water replenishment record, it is detected that the amount of hot water stored in the hot water storage tank satisfies a predetermined boiling start condition in a specific time zone. And control means for performing additional boiling operation by operating the up heating means, said control means is a temperature difference between the reheating before the start of the temperature of the bath water with a preset bath set temperature is above a certain value If it is determined that the remaining hot water is replenished and the remaining hot water replenishment record is recorded, the reheating start condition is changed in a direction in which it is easier to start reheating than when no remaining record is stored. A heat pump hot water storage type hot water supply device.   The boiling increase start condition is stored on the condition that, among a plurality of hot water temperature sensors provided on the side surface of the hot water storage tank, a specific hot water temperature sensor has become equal to or lower than a predetermined temperature, the remaining hot water replenishment record is recorded. In this case, the hot water storage temperature sensor provided at a lower position than the case where no record is stored is used as the specific hot water storage temperature sensor so that the boiling start condition is changed in the direction in which boiling increases easily. The heat pump hot water storage type hot water supply apparatus according to claim 1.   The boiling increase start condition is stored on the condition that, among a plurality of hot water temperature sensors provided on the side surface of the hot water storage tank, a specific hot water temperature sensor has become equal to or lower than a predetermined temperature, the remaining hot water replenishment record is recorded. 2. The heat pump according to claim 1, wherein the heating start condition is changed in a direction in which boiling starts easily by setting a predetermined temperature higher than that in the case where no record is stored. Hot water storage water heater.

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