JP4581939B2 - Hot water storage water heater - Google Patents

Description

  The present invention is provided with a heating system that performs heating operation using hot water in a tank, and when the water level of a water replenishing tank that stores hot water for heating load decreases, whether water is automatically refilled or manually refilled. The present invention relates to a hot water storage type water heater that can be selected.

Conventionally, an antifreeze liquid is used for a heating system of this type of hot water storage type water heater. By using antifreeze, it was not necessary to prevent freezing on the heating system side (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2004-20026

  However, the conventional configuration requires replenishment of antifreeze. The water in the antifreeze liquid evaporates over time, and the antifreeze liquid gradually decreases, and if it is left as it is, heating operation can no longer be performed. Therefore, it is necessary to periodically replenish the antifreeze liquid, and it did not have a function of detecting a drop in water level and performing automatic water replenishment.

  The present invention solves the above-described conventional problems. When tap water is used in a heating system, automatic water replenishment is automatically selected when water level is lowered due to evaporation of the water. At the same time, setting of automatic water replenishment that automatically activates freeze prevention operation to prevent freezing due to tap water, and when using antifreeze liquid in the heating system, manual replenishment and manual operation without freeze prevention operation The purpose is to select a refill setting.

  In order to solve the above-mentioned conventional problems, the hot water storage type water heater of the present invention performs a selection operation of selecting automatic replenishment setting or manual replenishment setting at an operation unit that operates on / off of heating operation. Provided, when automatic water replenishment is selected, when it is detected that the water level has dropped, water is automatically refilled, and when a decrease in the outside air temperature is detected, freeze prevention operation is performed.

  Thus, tap water can be used when automatic water replenishment is selected, and antifreeze can be selected when manual water replenishment is selected, so that a heating system can be freely selected according to the situation of the user.

  The hot water storage type water heater according to the present invention provides a selection operation for selecting automatic replenishment setting or manual replenishment setting at an operation unit that operates on / off of heating operation. When it is detected that the temperature has decreased, water can be automatically replenished, and when a decrease in the outside air temperature is detected, tap water can be used for the heating system by automatically performing the freeze prevention operation. In addition, depending on the user's situation, by selecting manual water replenishment, the antifreeze liquid can be used, and by inadvertent automatic water injection, tap water is mixed with the antifreeze liquid, resulting in performance degradation such as freezing and decay. Can be prevented.

  The first invention includes a tank for storing hot water, a circulation pump for circulating hot water in a heating load, a water replenishing tank for storing hot water circulating in the heating load, a water replenishing valve for supplying water to the water replenishing tank, and a water replenishing tank The water level detector detects that the water level has dropped, the outside air temperature detector detects the outside air temperature, and the operation part that turns on / off the heating operation. In a heating system that opens the refill valve and supplies water when the detection unit detects, automatic rehydration that opens the refill valve when the water level detection unit detects that the water level in the refill tank has dropped, or refills manually without opening the refill valve By selecting one of the manual water refills using the operation unit, when automatic water replenishment is selected, it is possible to automatically refill water when it is detected that the water level has dropped, and tap water can be used for the heating system.In addition, depending on the user's situation, by selecting manual water replenishment, the antifreeze liquid can be used, and by inadvertent automatic water injection, tap water is mixed with the antifreeze liquid, resulting in performance degradation such as freezing and decay. Can be prevented.

  In the second invention, in particular, in the first invention, when automatic water replenishment is selected, when it is detected that the outside air temperature detection unit has become a predetermined temperature or less, the circulation pump is started to prevent freezing of the heating load. Operates and does not perform freeze prevention operation when manual water replenishment is selected. When automatic water replenishment is selected, it automatically performs freeze prevention operation when tap temperature is detected and tap water is used for the heating system. be able to.

  In the third aspect of the invention, in particular, in the first aspect of the invention, when automatic water replenishment is selected, the operation unit performs selection of whether to permit or prohibit freezing prevention operation of the heating load. Even when tap water is used, it is possible to cope with cases where freezing prevention is unnecessary, such as the entire system being installed indoors.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram of a hot water storage type hot water heater according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes a tank for storing hot water, which has a hot water supply pipe 11 at the upper part and a water supply pipe 12 at the lower part of the tank 10. The water supply pipe 12 is connected from a water supply port 13 to which a water supply is connected through a pressure reducing valve 14 for reducing the water pressure. In the tank 10, hot water is separated into the upper part and water is separated into the lower part due to the difference in specific gravity, and when boiling the hot water in the tank 10, hot water is stored from the upper part of the tank 10, thereby forming a layer in a manner that the hot water is pushed down. Accumulated. When hot water is supplied from the hot water supply pipe 11, water is supplied from the water supply pipe 12 into the tank 10 and the tank 10 is always filled with hot water. A boiling pipe 15 connected from the lower part to the upper part is connected to the tank 10, and a boiling pump 16 and a heat source unit 17 are interposed in the boiling pipe 15. By driving the boiling pump 16, hot water in the lower part of the tank 10 is supplied to the heat source part 17, and after the hot water is overheated by the heat source part 17, the hot water is returned to the upper part of the tank 10 to be stored. At this time, the heat source unit 17 is a heat pump or a heater having a heat pump cycle mechanism.

  In general, a hot water storage type hot water heater is a night heat storage type hot water heater that uses cheap late-night power, and boils the entire amount of hot water in the tank 10 at night. Therefore, the user uses the hot water boiled at night for hot water supply in the daytime, and when the hot water in the tank 10 decreases, the hot water is heated by the expensive daytime power to prevent the hot water from running out. Will be performed. When the user supplies hot water to the currant 18 and the shower 19, the hot water supplied from the tank 10 via the hot water supply pipe 11 and the water decompressed by the pressure reducing valve 14 and supplied via the water supply pipe 12 are The mixing valve 20 performs mixing. The mixing valve 20 is driven so that the hot water supply temperature detection unit 21 reaches the target temperature.

  Next, the heating operation of the heating system will be described. When the user performs the heating operation, the heating operation switch 23 of the operation unit 22 is turned on. When the heating operation switch 23 is turned on, the water temperature of the heating load 26 is checked by the incoming water temperature detection unit 25 by driving the circulation pump 24. The heating load 26 includes a floor heating panel, a bathroom dryer, a hot air fan convector, and the like. By driving the heating pump 28 when the temperature detected by the incoming water temperature detection unit 25 is lower than the temperature set by the heating temperature switch 27 configured by the plus switch 35 and the minus switch 36 of the operation unit 22. The hot water at the top of the tank 10 flows into the heat exchanger 29. The heating pump 28 is adjusted and driven so that the tapping temperature detector 34 reaches a temperature set by the heating temperature switch 27. The hot water in the tank 10 is returned from the heat exchanger 29 to the lower part of the tank 10 after heating the hot water of the heating load 26. The hot water temperature of the heating load 26 gradually rises due to heating by this heat exchange, and when the temperature detected by the incoming water temperature detection unit 25 exceeds the temperature set by the heating temperature switch 27, the heating pump 28 is stopped and heated. Exit.

  Next, a system for automatically refilling the heating system will be described. On the secondary side of the heating system, there is a water replenishing tank 30, and water is supplied from the water supply pipe 12 through the water replenishing valve 31. The water refill valve 31 is normally closed. When the water level detector 32 provided in the water refill tank 30 detects a drop in the water level, the water refill valve 31 is opened to refill the water refill tank 30. And if the water level detection part 32 detects a water level raise, the water refill valve 31 will be closed and water replenishment will be complete | finished. By repeating water replenishment in this way, even when the water level drops due to evaporation of water, it is not necessary for the user to replenish regularly, and it is possible to prevent the heating operation from being disabled due to forgetting to replenish. it can.

  Next, the freeze prevention operation of the heating system will be described.

  First, when the outside air temperature detection unit 33, the incoming water temperature detection unit 25, or the hot water temperature detection unit 34 detects a decrease in the outside air temperature, the circulation pump 24 is driven. At this time, for a while after the circulation pump 24 is driven, a period during which accurate temperature detection cannot be performed is caused by the temperature of the hot water remaining in the pipe up to the heating load 26. Therefore, temperature detection is waited until a predetermined time has elapsed. If the incoming water temperature detection unit 25 has reached a predetermined freeze prevention release temperature set higher than that at the start of freeze prevention after a predetermined time has elapsed, the circulation pump 24 is stopped and the freeze prevention operation is ended. . At this time, since the indoor temperature is usually higher than the outdoor temperature, the water temperature inside the heating load 26 is also higher than the outside air temperature, and the hot water of the heating load 26 is driven by the circulation pump 24. It will circulate and freeze prevention operation will be performed. However, when the water temperature inside the heating load 26 decreases due to the repetition of the freeze prevention operation, or when the original room temperature itself is low, the predetermined freeze prevention release temperature may not be reached. In that case, by driving the heating pump 28, the hot water of the heating load 26 is heated by the heat exchanger 29, and the freezing prevention is surely performed. In addition, in the case where the outside air temperature is detected by the outside air temperature detection unit 33 and the freeze prevention is performed, a period for prohibiting the detection of the outside air temperature may be provided so that the freeze prevention operation is not started again immediately after the completion of the freeze prevention. Shall.

  In the heating system configured as described above, selection of the water replenishment method will be described below.

  First, in normal operation, automatic rehydration and manual rehydration cannot be selected. In order to select the water replenishing method, the user switches to the water replenishing method by continuously pressing a certain switch for a long time, for example, by pressing the heating operation switch 23 for 10 seconds. Further, as another switching method, it may be possible to switch to the selection of the water replenishment method by simultaneously pressing two or more switches, for example, pressing the plus switch 35 and the minus switch 36 simultaneously. Accordingly, it is possible to prevent an erroneous setting due to an operation that the user easily switches the selection of the water replenishment method. Next, when switching to the refilling method selection, the current refill setting is displayed on the display unit 37 of the operation unit 22. The current water replenishment setting is stored in the storage unit 38, and its contents are displayed. For example, each time the plus switch 35 is pressed, the automatic water refill setting and the manual water replenishment setting are alternately displayed, or each time the minus switch 36 is pressed, the automatic water replenishment setting and the manual water replenishment setting are alternately displayed. Change the setting. After switching the refilling setting, the refilling setting is confirmed by pressing the confirmation switch 39 or by no operation for a predetermined time. Then, when the water refill setting is confirmed, the contents are stored in the storage unit 38. Thereby, it is possible to prevent the water supplement setting from being switched due to a power failure.

  Further, in the hot water storage type hot water heater according to the present embodiment, the freeze prevention operation of the heating system is performed only when automatic water replenishment is selected as the water replenishment method for the heating system. As a result, when manual water replenishment is selected, it can be determined that antifreeze is used in the heating system, and unnecessary freezing prevention operation can be prevented, and the circulation pump 24 suddenly starts to be driven by the user. You can get rid of distrust. When automatic water replenishment is selected, it is determined that tap water is used in the heating system, and freezing can be prevented automatically.

  Further, in the hot water storage type water heater according to the present embodiment, only when automatic water replenishment is selected as the water replenishment method for the heating system, the operation unit 22 can select whether to permit or prohibit the freeze prevention operation. Yes. In order to select permission / prohibition of the freeze prevention operation, for example, by pressing the menu switch 40, an operation such as switching the screen of the display unit 37 to permission / prohibition is performed. Next, when the screen is switched, the current freeze prevention operation permission / prohibition setting is displayed on the display unit 37. The current permission / prohibition setting is stored in the storage unit 38, and the contents are displayed. Then, for example, permission and prohibition are alternately displayed each time the plus switch 35 is pressed, or setting is switched by a switch operation such that permission and prohibition are alternately displayed each time the minus switch 36 is pressed. After the change of the permission / prohibition setting, the setting is confirmed by pressing the confirmation switch 39 or by no operation for a predetermined time. Then, when the setting is confirmed, the contents are stored in the storage unit 38. This can prevent the permission / prohibition setting from being switched due to a power failure. Thereby, even when tap water is used for the heating system, it is possible to cope with the case where freezing prevention is unnecessary, for example, the entire system is installed indoors.

  As described above, the hot water storage type hot water heater according to the present invention includes a heating system, and when the water level of a replenishing tank for storing hot water of the heating load is lowered, whether to replenish water automatically or manually. Can be applied to applications such as electric water heaters and heat pump water heaters.

The block diagram of the hot water storage type hot water heater in Embodiment 1 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Tank 22 Operation part 24 Circulation pump 30 Refill tank 31 Refill valve 32 Water level detection part 33 Outside temperature detection part

Claims (3)

A tank for storing hot water, a circulation pump for circulating hot water for heating load, a water replenishing tank for storing hot water circulating to the heating load, a water replenishing valve for supplying water to the water replenishing tank, and a water level in the water replenishing tank are lowered. A water level detection unit for detecting that the water level has been detected, an outside air temperature detection unit for detecting the outside air temperature, and an operation unit for operating on / off of the heating operation. In the heating system that opens the refill valve when supplying water and detects that the water level in the refill tank has dropped, the water level detection unit detects that the water replenishment valve is automatically opened or the refill valve is not opened manually. A hot water storage type hot water supply machine that selects any one of manual replenishing water for replenishing with the operation unit. When automatic water replenishment is selected, when the outside air temperature detector detects that the temperature has fallen below the specified temperature, the circulation pump is started to perform freezing prevention operation of the heating load, and when manual water replenishment is selected, freezing prevention operation is performed. The hot water storage type water heater according to claim 1, which is not present. The hot water storage type hot water heater according to claim 1, wherein when automatic water replenishment is selected, the operation unit selects whether to permit or prohibit freezing prevention operation of the heating load.

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