JP5706304B2 - Hot water storage bath system - Google Patents

Description

  The present invention relates to a hot water storage bath apparatus that prevents freezing of residual water in a bath heat exchanger provided in a hot water storage tank.

  Conventionally, in this type of hot water storage hot water supply system, at the freezing risk temperature, the bath circulation pump is driven to the minimum to circulate the bath water in the bath circulation circuit to prevent freezing. Therefore, since the circulating water circulates to the bath heat exchanger in the hot water storage tank, there is a problem that the hot water temperature of the hot water tank gradually decreases. To prevent this, the bath circulation circuit It is equipped with a bypass pipe that bypasses the bath heat exchanger and a bath three-way valve that switches the flow path, and during freeze prevention operation, the flow path is switched so that the circulating water circulates the bypass pipe instead of the bath heat exchanger. By doing so, it was possible to prevent freezing without lowering the temperature of the hot water storage. (See Patent Document 1.)

JP 2003-50048 A

  By the way, in this conventional system, when freeze-proof operation is performed in a state where there is no residual water in the bathtub, residual water in the bath circulation circuit from the bypass pipe to the bathtub is drained, but residual water in the bath heat exchanger is drained. However, since it remains as it is, there is a problem that when the boiling of the hot water storage tank is stopped for travel or the like, the remaining water in the bath heat exchanger will be frozen.

  This invention pays attention to this point and solves the above-mentioned problems. In particular, the construction thereof includes a hot water storage tank for storing hot water, heating means for heating the hot water in the hot water storage tank, and hot water provided in the hot water storage tank. A bath heat exchanger for exchanging heat, a bath circulation circuit for communicating the bath heat exchanger and the bathtub, and a bath circulation pump provided in the bath circulation circuit for circulating the bath water through the bath heat exchanger And a bypass pipe that bypasses the bath heat exchanger in the bath circulation circuit between the bath circulation pump and the bath heat exchanger, and whether the bypass pipe is circulated or the bath heat exchanger is circulated in the bath circulation circuit If the bath circulation circuit has no remaining hot water, the bath three-way valve is open on the bypass pipe side and the bath heat exchanger side is closed. Drive the pump After draining the residual water in the pipe to the bathtub from the scan line is obtained by such a predetermined time holding the bath three-way valve as the bath heat exchanger-side opening for draining the residual water in the bath heat exchanger.

  As described above, according to the present invention, when there is no remaining hot water in the bathtub in the danger of freezing, first the bypass pipe side is opened and the bath circulation pump is driven, so that the remaining pipe in the pipe from the bypass pipe to the bathtub is left. By draining water, and then holding the bath three-way valve on the side of the bath heat exchanger for a predetermined time and draining the remaining water in the bath heat exchanger, there is no remaining water in the bath circulation circuit. There is no worry about freezing, it is economical without power consumption, and it can be used safely.

The schematic block diagram of one Embodiment of this invention. Explanatory drawing which shows the waste_water | drain state in the bypass pipe side opening of the same three-way valve. Explanatory drawing which shows the waste_water | drain state in the bath heat exchanger side opening of the same three-way valve. The flowchart of the freeze prevention driving | operation in the state without residual water in the bathtub.

Next, an embodiment of the present invention will be described based on a hot water storage bath apparatus illustrated in the drawings.
1 is a cylindrical hot water storage tank that uses heating means 2 composed of a heat-pump unit using carbon dioxide refrigerant to boil hot water in the midnight hours when the unit price of contract power by time is low and store hot water. The lower part is connected to a water supply pipe 3 for supplying water, and the upper part is connected to a hot water discharge pipe 4 for discharging hot water stored in a hot water tap (not shown).

  5 is composed of a hot water supply pipe 4 on one side, a first water supply bypass pipe 6 branched from the water supply pipe 3 on the other side, and a SAM type (shape memory alloy built-in type) electric three-way valve with a hot water supply pipe 7 connected to the center. The hot water mixing valve mixes the hot water from the hot water supply pipe 4 with the water supplied from the first water supply bypass pipe 6 and supplies the hot water at a set hot water temperature set by the kitchen remote controller 8. The hot water side opening degree of the tapping pipe 4 and the water side opening degree of the first water supply bypass pipe 6 are adjusted by feedforward control from the hot water supply temperature, the hot water temperature, and the hot water set temperature by the hot water supply thermistor 9 provided in the pipe 7. .

  10 is connected to a hot water discharge pipe 11 branched from the hot water discharge pipe 4 on one side, a second water supply bypass pipe 12 branched from the first water supply bypass pipe 6 on the other side, and a hot water filling circuit 13 connected to the center. A bath mixing valve composed of a three-way valve mixes high-temperature water from the bath outlet pipe 11 and water from the second water supply bypass pipe 12 so that the set temperature set by the bathroom remote controller 14 is reached. The hot water side opening of the bath hot water discharge pipe 11 and the water side opening of the second water supply bypass pipe 12 are adjusted by feedforward control from the hot water temperature, the hot water temperature, and the bath set temperature. Hot water at a preset bath temperature is supplied to the hot water filling circuit 13, and a set amount of hot water or additional hot water is applied to the bathtub 16 at a preset temperature via a bath circulation circuit 15 communicated with the hot water filling circuit 13.

  A hot water flow sensor 17 is provided in the hot water filling circuit 13 and counts the flow rate of hot water filling. The hot water filling electromagnetic valve 18 is provided downstream to start counting. Further downstream, two check valves 19 and 20 that allow flow in the hot water filling direction but prevent reverse flow are provided, and between the two check valves 19 and 20 and the bath mixing valve 10. A drain pipe 22 having a drain valve 21 communicating with the hot water flow sensor 17 is provided.

  The bath circulation circuit 15 that connects the bathtub 16 and the bath heat exchanger 23 provided in the upper part of the hot water storage tank 1 includes a bath thermistor 24 that detects the bath water temperature in the vicinity of the hot water filling circuit 13 connected thereto, A bath flow sensor 25 that detects the presence or absence of residual water is provided. 26 is a self-priming bath circulation pump that circulates and heats bath water between the bathtub 16 and the bath heat exchanger 23, 27 is a water level sensor that detects the water level in the bathtub 16, and 28 bypasses the bath heat exchanger 23. The bath three-way valve provided in the bypass pipe 29 is configured to switch between passing the bath water through the bath heat exchanger 23 side or not passing through the bypass pipe 29 side. The bath water is sucked by the driving of the bath circulation pump 26 and flows into the bath heat exchanger 23 from the upper side of the bath heat exchanger 23, flows out from the lower side of the bath heat exchanger 23, and the bath three-way valve 28 and Circulation returning to the bathtub 16 through the bath circulation pump 26, especially by circulating from the top to the bottom in the bath heat exchanger 23, avoids contact with the hot water stored at a reduced temperature, so that the hot hot water is always hot. Heat exchange only with, very efficient Is shall.

  30 is a control means comprising a microcomputer connected to the kitchen remote control 8 and the bathroom remote control 14 for controlling hot water supply, hot water bathing, additional hot water, etc. Various sensors are connected to the input side and the outside temperature is detected. When the outside air temperature sensor 31 is connected and the outside air temperature falls below 0 ° C., the freeze prevention operation is started, the bath three-way valve 28 is opened on the bypass pipe 29 side, and the bath circulation pump 26 is driven at the minimum rotation speed for 10 minutes. Stop and check whether the bath flow sensor 25 has detected the remaining water. Without any remaining water, the bath three-way valve 28 is opened on the side of the bath heat exchanger 23 and left for 10 minutes. Residual water is drained to prevent freezing, and the bath flow sensor 25 performs control to open the bypass pipe 29 for another 10 minutes when there is residual water.

A water supply thermistor 32 is provided in the water supply pipe 3 to detect the water supply temperature, and 33 is a pressure reducing valve for reducing the water supply pressure.
Reference numeral 34 denotes a heating circulation circuit including an outward pipe 35, a return pipe 36, and a heating circulation pump 37 that connect the hot water storage tank 1 and the heating means 2 so that hot water can circulate.
38, 39, 40, 41, 42 are hot water storage temperature sensors provided above and below the outer peripheral surface of the hot water storage tank 1, and 43 is a pressure relief valve provided in the hot water discharge pipe 4.

Next, the operation of this embodiment will be described.
In the midnight time zone of the contract power now, the low-temperature water in the lower part of the hot water tank 1 is boiled by the heating means 2 by the heating circuit 34, the hot water is returned to the upper part of the hot water tank 1, and this circulation is repeated sequentially from 23:00. The hot water is stored in the entire hot water storage tank 1 by 7 o'clock the next morning.

  And the hot water in this hot water storage tank 1 is mixed with the hot water from the hot water discharge pipe 4 and the hot water from the 1st hot water bypass pipe 6 with the hot water supply mixing valve 5, and is utilized for hot water supply as hot water of hot water supply preset temperature. Is.

  Next, when performing bath hot water supply such as hot water filling, the controller 30 opens the hot water solenoid valve 18 and drives the bath mixing valve 10 by instructing hot water filling with the kitchen remote control 8 or the bathroom remote control 14. By gradually opening the bath discharge pipe 11 in a closed state, hot water from the upper part of the hot water storage tank 1 is supplied through the bath discharge pipe 11, while water is supplied from the second water supply bypass pipe 12. The hot water and water supply are bath mixing valves 10, and the hot water side opening of the bath hot water discharge pipe 11 and the water side opening of the second water supply bypass pipe 12 are determined by the control means 30 from the hot water temperature, the water supply temperature, and the bath set temperature. Is adjusted by feedforward control, and hot water filling is performed at a set temperature to the bathtub 16 via the hot water filling circuit 13 and the bath circulation circuit 15 at a sufficient flow rate for both high-temperature water and water supply.

  Next, the freezing prevention operation in the state where there is no residual water in the bathtub 16 will be described according to the flowchart of FIG. 4. In step S1, it is determined whether the outside air temperature detected by the outside air temperature sensor 31 is 0 ° C. or less. Proceeding to step S2, anti-freezing operation is started, and proceeding to step S3, the bath three-way valve 28 is opened on the bypass pipe 29 side, the bath heat exchanger 23 side is closed, and in step S4, the bath circulation pump 26 is set at the minimum rotational speed. By driving while obtaining silent and power saving, the remaining water in the bath circulation circuit 15 from the bypass pipe 29 to the bathtub 16 is drained through the bathtub 16 as shown in FIG.

  Then, in step S5, it is determined whether or not 10 minutes have elapsed. In step S6, the process proceeds to step S6 and the drive of the bath circulation pump 26 is stopped. Then, the process proceeds to step S7 and immediately before the bath circulation pump 26 is stopped. No. 25 has detected the remaining water, the process proceeds to step S8 with NO remaining water, the bath three-way valve 28 is opened on the side of the bath heat exchanger 23 and the bypass pipe 29 is closed, and 10 minutes have passed in this state. In step S9, the residual water in the bath heat exchanger 23 is drained through the bath three-way valve 28 and the bathtub 16 as shown in FIG.

  Further, if there is residual water in step S7, the process proceeds to step S10 with YES, and the bath three-way valve 28 is again opened on the bypass pipe 29 side and the bath heat exchanger 23 side closed, and then the process proceeds to step S11 to see if this state has elapsed for 10 minutes. That is, in the normal time when there is remaining hot water in the bathtub 16, the water is returned to the original without draining the remaining water in the bath heat exchanger 23, and this is sequentially repeated.

  Thus, when there is no remaining hot water in the bathtub 16, even if the hot water storage tank 1 is not boiled up by draining the residual water in the bath circulation circuit 15 and the bath heat exchanger 23 by performing the freeze prevention operation. In this case, the remaining water in the bath heat exchanger 23 that remains without being drained in normal freezing prevention operation can be drained only by switching the bath three-way valve 28. This is a major feature.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 2 Heating means 15 Bath circulation circuit 16 Bath 23 Bath heat exchanger 26 Bath circulation pump 28 Bath three-way valve 29 Bypass pipe 30 Control means

Claims (1)

A hot water storage tank for storing hot water, heating means for heating the hot water in the hot water storage tank, a bath heat exchanger provided in the hot water storage tank for exchanging heat with hot water, and the bath heat exchanger and the bathtub communicate with each other. A bath circulation circuit, a bath circulation pump that is provided in the bath circulation circuit and circulates the bath water in the bath heat exchanger to reheat, and a bath circulation circuit between the bath circulation pump and the bath heat exchanger, What is provided with a bypass pipe that bypasses the bath heat exchanger and a bath three-way valve that switches between circulating the bypass pipe in the bath circulation circuit or circulating the bath heat exchanger, To prevent freezing, when there is no remaining hot water in the bathtub, the bath three-way valve is opened on the bypass pipe side and the bath heat exchanger side is closed, and the bath circulation pump is driven to drain the remaining water in the pipe from the bypass pipe to the bathtub. After, take a bath three-way valve Storage-type bath apparatus, characterized in that the exchanger-side opening to hold a predetermined time so as to drain the remaining water in the bath heat exchanger.

Images