JP2013221714A - High-efficiency circulation heat insulation method of water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold water supplied to an EcoCute (R) for business use always at a water supply temperature in such a manner that an operation to supply water always at a plus and low temperature is performed and the heat of the operation is used for circulation heat insulation according to the fact that the EcoCute for business use is characterized in that the efficiency thereof is higher as the temperature of supplied water is a plus and lower.SOLUTION: In a high-efficiency circulation heat insulation system of a water heater, as a means of improving the efficiency of the whole system by achieving a high-efficiency operation of an EcoCute in the day and night, the means uses high-temperature heat corresponding to a temperature of 5°C, of the high-temperature heat of the operation from a low temperature (5-25°C) to a high temperature (90-70°C), for circulation heat insulation during nighttime heat storage. During daytime heat dissipation, when an amount of use of hot water supply is large, high-temperature water flows in an upper chamber, and the heat of the high-temperature water corresponding to 5°C is used for circulation heat insulation, and when the amount of use of the hot water supply is small, the EcoCute is placed in operation (from high efficiency and low temperature to high temperature), and circulation heat insulation is performed by using high-temperature water in the chamber if the upper chamber reduces to 70°C.

Description

  The present invention relates to a high-efficiency circulating heat retaining method in a water heater.

  Eco-cute for business use that uses conventional nighttime electricity (Eco-Cute is a model that uses heat pump technology and uses carbon dioxide instead of chlorofluorocarbon as a refrigerant among electric water heaters that can boil hot water with the heat of air. The secondary circulation system of the heat storage system used is a system that uses a heat pump (annual average cop = 2.3) with a small temperature difference (Δt = 5 ° C) of another heat source, distribution mounting type There are a method using an electric heater (cop = 1.0) and a method of using production heat by a business eco-cute provided with a sub-tank. Among these systems, the previous two methods have low equipment efficiency. It was a thing.

  The sub-tank system uses hot water from the high temperature (90 ° C to 70 ° C) to about 60 ° C by putting hot water from the high temperature (90 ° C to 70 ° C) part of the eco-cute for business use into the circulation system. In this way, the circulation line is kept warm.

  However, depending on the load situation, there are many cases where it falls into the situation where the eco-cute driving efficiency for business use is greatly reduced as described below.

1) During night heat storage: There is almost no hot water supply load.
Circulation load> High-temperature water heat supply (90 ° C → 60 ° C) In this case, 55 ° C medium-temperature water flows from the sub tank to the main tank, and this medium-temperature water enters the eco-cute. C → tapping hot water 90 ° C.) The efficiency drops to about COP = 1.8.
2) During heat dissipation during the daytime: The hot water supply load is large.
Circulation load <High-temperature water heat supply (90 ° C. → 60 ° C.) In this case, when the hot water supply load is large, the original heat quantity of heat insulation is small, and when the hot water supply load is small, the heat insulation heat quantity is large.

  That is, when the heat retention heat amount is large, the medium temperature water enters the sub tank, and if it continues, the medium temperature water enters the main tank, which is a factor that lowers the efficiency of later eco-cute operation.

  Therefore, in general, a facility that circulates 24 hours has a drawback in that the efficiency of the entire system is lowered despite the use of Ecocute. For example, as in Patent Document 1.

Utility Model Registration No. 3158272

  Therefore, this problem is to always use the incoming water temperature for the business eco-cute as the water supply temperature, and as a characteristic of the eco-cute, the lower the incoming water temperature is, the higher the efficiency, the better. Providing a high-efficiency circulating heat insulation method for hot water heaters that can drastically improve the overall efficiency of heat storage and circulation by always performing the operation of entering water at that temperature and using the heat generated by the operation for circulation heat insulation. There is.

  In the conventional circulation heat insulation, hot water was supplied to the circulation line to keep it warm, but in facilities with a large circulation load (such as hospitals that operate for 24 hours), medium temperature water flows not only into the sub tank but also into the main tank. However, the actual situation is that the temperature of water entering the Eco-Cute for business use at night becomes medium-temperature water, resulting in a significant drop in COP.

  Therefore, in order to solve the above-mentioned problems, it is to develop and provide a high-efficiency circulating heat insulation method in a water heater that draws out high-efficiency operation of an eco-cute for business use day and night, and greatly improves the efficiency of the entire system. .

  According to this invention, conventional heat insulation includes a heat pump (separate heat source), an electric heater (separate heat source), a sub-tank system (same heat source but with reduced cop), etc. Although the cost has increased, it has extremely beneficial effects such as energy saving, cost saving, and initial cost saving by using the heat of night heat storage and eco-cute high efficiency operation with the same heat source.

It is a piping system diagram showing one example of this invention.

  The present invention will be described in detail below. The present invention is not limited to the following description, and can be appropriately changed without departing from the gist of the present invention.

  An embodiment of the present invention will be described in detail with reference to the drawings. In a high-efficiency circulating heat insulation system in a hot water heater, the highly efficient operation of a business eco-cute (2) is drawn out regardless of day or night, and the efficiency of the entire system is improved. As a means, during the nighttime heat storage, the heat raised from the low temperature region (5 ° C to 25 ° C) in the temperature stratified heat storage tank (1) to the high temperature region (90 ° C to 70 ° C), Use about 5 ° C for circulation insulation and perform circulation insulation with high efficiency operation. During daytime heat dissipation, the amount of hot water used increases, and high-temperature water (90 ° C. to 70 ° C.) is gradually consumed through the upper chamber. At this time, about 5 ° C. of the high temperature water flowing into the chamber is used for the circulation heat insulation, and the heat insulation for heat storage is performed using the heat of high efficiency. In addition, during the daytime and chasing operation, high-efficiency operation is performed in the same operation state as during nighttime high heat.

  The temperature stratified heat storage tank (1) has a temperature between 60 ° C. and 50 ° between the lower low temperature range (5 ° C. to 25 ° C.) and the upper high temperature range (90 ° C. to 70 ° C.). It has a mixing zone of ° C.

  During nighttime heat storage, low temperature water (water supply) of 5 ° C. to 25 ° C. is supplied to the Ecocute (2) by the pipe (A) and heated by the Ecocute (2) to 70 by the pipe (B). High temperature water (° C-90 ° C) is supplied to the upper chamber in the tank. This hot water is supplied to the heat exchanger (3) by the hot water circulation heating pump (4) attached to the pipe (D), and heat of about 5 ° C. is supplied to the upper chamber by the pipe (E). Go home. Thereby, the hot water supply piping is kept warm (temperature maintenance).

  In this case, the eco-cute is operated (high efficiency low temperature → high temperature) to provide high temperature water in the chamber, and the high temperature water is used to perform circulation heat insulation. Composed.

  The thermal stratification type heat storage tank (1) is from the low temperature region (5 ° C to 25 ° C) of the heat storage tank (1) toward the eco-cute for business use (2), and the pipe (A) Deliver low-temperature water at 25 ° C. Further, from the eco-cute for business use (2), the pipe (B) is used for the high temperature region (90 ° C to 70 ° C) of the heat storage tank (1) through the electric three-way valve (5a). It supplies high-temperature water at 70 ° C.

  In addition, hot water of 65 ° C. is supplied from the high temperature region (90 ° C. to 70 ° C.) of the temperature storage tank type heat storage tank (1) via the mixing valve (6) to the pipe (K) and the pipe (J). Hot water at ° C.

  A heat exchanger (3) is provided between the pipe (I), which is a hot water return pipe, and the pipe (J). When the temperature of the hot water return decreases with the high-temperature water in the heat storage tank (1), the hot water circulation is increased. Turn the heat pump (4) on and off to keep the circulation warm.

  The pump (4) is operated only when the temperature needs to be raised to prevent wasteful heat loss.

  Because of the hermetic heat storage system, the same amount of water as that used for hot water flows into the lower chamber from the pipe (L), and forms an adult tank due to the temperature difference in the tank.

  According to the present invention, by establishing a manufacturing technology for a high-efficiency circulating heat insulation system in a hot water heater, and manufacturing and selling it based on the manufacturing technology, energy saving can be achieved and there is industrial applicability.

DESCRIPTION OF SYMBOLS 1 Thermal stratification type heat storage tank 2 Business-use Ecocute 3 Heat exchanger 4 Hot water circulation heating pump 5a, 5b, 5c Electric three-way valve 6 Mixing valve A, B, C, D, E, F, G, H, I, J, K piping

Claims (1)

In a high-efficiency circulating heat insulation system in a water heater, as a means to bring out the high-efficiency operation of the eco-cute for business, day or night, and improve the efficiency of the entire system,
During the nighttime heat storage, the high temperature heat of operation from low temperature (5 ° C to 25 ° C) to high temperature (90 ° C to 70 ° C) is used for circulating heat,
During daytime heat dissipation, when hot water use is large, high-temperature water flows into the upper chamber, and the heat of this high-temperature water is used for 5 ° C circulation heat insulation. When the amount of hot water supply is small, the upper chamber is 70 When it falls to ° C, it keeps warm with that heat,
A high-efficiency circulating heat insulation method characterized by operating the eco-cute for business use (high efficiency low temperature → high temperature) and circulating heat insulation using high temperature water in the chamber.

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