JP2002257414A - Solar water heater, auxiliary heat source device, and solar hot water supply apparatus combining them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar hot water supply apparatus contributing to energy saving by effectively using high temperature hot water stored by utilizing solar heat. SOLUTION: The solar hot water supply apparatus comprises a hot water storage tank 4 to store hot water heated by solar heat; a temperature sensor 23 to detect a hot water temperature; a mixing device 5 to mix hot water and cold water together; a temperature sensor to detect a hot water temperature after mixture; and a first control part 6. A solar water heater 1 wherein an outlet hot water temperature is controlled through hot-water/water mixing adjustment by using a set hot water temperature (TR) as a control temperature in automatic filling of a bathtub with hot water and in supply of hot water other than the automatic filling of the bathtub with hot water, the outlet hot water temperature is controlled by using TR-α as a control temperature, and an auxiliary heat source apparatus 11, provided with a temperature sensor 17 to detect the temperature of hot water on the inlet side, a heat exchanger 13, branched terminal pipe lines, a combustion heating part 12 to heat the branched terminal pipe-lines and the heat exchanger 13, and a second control part 14, and effecting control that when an incoming hot water temperature is lower than TR-β, a combustion heating part is operated, and when the incoming hot water temperature is not lower than TR-β, the combustion heating part is stopped are interconnected in series.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar water heater, an auxiliary heat source, and a solar water heater combining these.

[0002]

2. Description of the Related Art A general-purpose instantaneous auxiliary heat source device (such as a gas instantaneous water heater) has a lower limit for its heating capacity and cannot adjust the temperature below a predetermined width. For example, in the case of a general gas instantaneous water heater, the lower limit of the heating capacity is about 2.5 (No. 1 is the capacity to raise 1 liter of water per minute to 25 ° C,
For example, the temperature is about 20 ° C. per liter of water to 45 ° C.), which is a heating capacity capable of raising the temperature by about 6.3 ° C. with respect to the amount of hot water per 10 liters. For this reason,
If the hot water temperature supplied from the solar water heater is close to the remote control set temperature (TR), the hot water is superheated to a hot water temperature that greatly exceeds the remote control set temperature.

[0003] When a combination of an instantaneous auxiliary heat source and a solar water heater is used to supply hot water having a temperature corresponding to a desired temperature by a control system, first, in order to avoid the overheating, the solar heat is supplied in the solar water heater. The hot water that has been boiled by heat exchange (stored in the hot water storage tank) is once diluted with water supplied through a separate pipe to make the temperature sufficiently lower than the desired temperature (for example, about 30 ° C.), The conventional method is to supply the heat to the instantaneous auxiliary heat source device, and then to heat the auxiliary heat source device to a desired temperature set by a remote controller and supply the heat.

[0004]

However, it is a waste of energy to reduce the temperature of the hot water in the hot water storage tank to about 30 ° C. with water and reheat the same. Further, if the water is diluted in this manner, the hot water stored in the tank cannot be used up sufficiently. The present invention solves such a problem, that is, a solar water heater that effectively uses high-temperature hot water stored using solar heat and thus contributes to energy saving, an auxiliary heat source device thereof, and a solar water heater that combines these. It is to provide.

[0005]

In order to achieve the above object, the present invention has the following configuration. That is, the present invention (first invention) is a solar water heater 1 to which an auxiliary heat source device 11 is connected at an outlet side, wherein the solar water heater 1 is a hot water storage tank for storing hot water heated by solar heat. 4 and a temperature sensor 23 for detecting the hot water temperature (Th) of the hot water storage tank 4
A mixing device 5 for mixing the hot water from the hot water storage tank 4 and the water supplied from the branch pipe 22, a temperature sensor for detecting the temperature of the hot water after mixing, and a first control unit 6 for controlling the operation of these components.
In the bathtub automatic hot water filling, the hot water mixing adjustment and control system controls the outlet hot water temperature using TR as a control temperature, and in hot water supply other than the bathtub automatic hot water filling, the hot water mixing adjustment and control system , TR-α as a control temperature to control the outlet hot water temperature. Where T
R indicates a desired tapping temperature or a set temperature, and α indicates a positive predetermined temperature (° C.).

Here, "the hot water temperature of the hot water storage tank (Th) is controlled by the hot water mixing adjustment and control system using TR (or TR-α) as the control temperature to control the outlet hot water temperature."
Is equal to or higher than the desired tapping temperature (TR), in the automatic bathtub filling, it means that the outlet hot water temperature is adjusted to TR by diluting with water by a hot water mixing adjustment and control system. In hot water supply other than automatic hot water filling, the outlet hot water temperature is reduced by TR-
It means to adjust to α.

On the other hand, if the hot water temperature (Th) of the hot water storage tank is lower than the desired hot water temperature (TR), the meaning will be lost and will be further described. "(In the case of bathtub automatic hot water filling) the hot water temperature of the Th is maintained without being diluted by water without controlling the outlet hot water by using the hot water mixing adjustment and control system with TR as the control temperature." Means to supply. For hot water supply other than bathtub automatic hot water filling, "the hot water mixing tank adjusting and controlling system controls the outlet hot water temperature using TR-α as a control temperature" means that the hot water temperature (Th) of the hot water storage tank is TR- If the temperature is lower than α, the water is not diluted with water and supplied at the hot water temperature of Th, and TR-α
As described above, when the value is less than TR, it means to adjust to TR-α by diluting with water.

Here, the value of α can be selected to be an appropriate value around 10 ° C., but preferably (H × 25) ÷
Calculate and find Q + K. Here, H is the lower limit value (number) of the heating capacity of the auxiliary heat source device, Q is the amount of mixed hot water (L / min) by the flow rate sensor, and K is the offset temperature (° C.) of the hot water temperature fluctuation.

[0009] The present invention (second invention) also relates to an auxiliary heat source. That is, the auxiliary heat source device 11 connected to the outlet side of the solar water heater 1,
Comprises, in order from the inlet side, a temperature sensor 17 for detecting the inlet-side hot water temperature, a heat exchanger 13, and a branched end line, and a combustion / heating unit 12 for heating the heat exchanger 13. A second control unit 14 for controlling the operation, the combustion heating unit 12 is activated when the temperature of the incoming hot water is lower than TR-β, and the combustion heating unit 1
Reference numeral 2 denotes an auxiliary heat source that is controlled to stop.
Here, β indicates a positive predetermined temperature (° C.).

When the auxiliary heat source device main body is a gas instantaneous water heater, a water flow detecting device 16 is usually arranged in the middle of the inlet side pipe line, and when the hot water flow supplied from the solar water heater becomes less than a predetermined value. The combustion heating unit 12 is forcibly stopped.

[0011] The present invention (third invention) also relates to a solar water heater in which the solar water heater and the auxiliary heat source are connected in order from the upstream. At this time, it is preferable to select a value equal to or smaller than α (absolute value) as β (absolute value) for the control temperature TR-β of the hot water temperature on the auxiliary heat source device side. In a solar water heater in which the solar water heater and the auxiliary heat source device are connected, a temperature sensor for detecting a hot water temperature on an outlet side of the solar water heater and a temperature sensor for detecting a hot water temperature on an inlet side of the auxiliary heat source device are as follows. Alternatively, one of them can be omitted and the other temperature sensor can also be used.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings. In addition, a gas instantaneous water heater is used as the auxiliary heat source device main body. FIG. 1 is a configuration diagram of an example of a solar water heater, an auxiliary heat source device, and a solar water heater combined with each other according to the present invention. FIG. 2 is a flowchart of temperature control (solar water heater side) of the solar water heater according to the present invention. FIG. 3 shows a flowchart of hot water supply control (auxiliary heat source unit side) according to the present invention. The remote controller 15 for setting the hot water supply temperature is controlled by the second controller 14 via the remote controller code 18.
Is connected to the remote controller code 1
9 is connected to the first control unit 6 on the solar water heater side. The hot water supply temperature (set temperature; TR) and the bathtub automatic filling instruction set by the remote controller 15 are transmitted not only to the second control unit 14 on the auxiliary heat source unit side but also to the solar water heater via the second control unit 14. It is also transmitted to the first control unit 6 on the side.
Thereby, the solar water heater can also recognize the hot water supply temperature (that is, the set temperature) desired by the user and the automatic hot water supply state of the auxiliary heat source device. The remote control 15
The data communication from the first control unit 6 to the first control unit 6 via the second control unit 14 may be a method of connecting a code on the same communication line and directly receiving data.

A hot water storage tank 4 is provided in the solar water heater 1, and water (or antifreeze) heated by a heat collector 10 installed on a roof or the like is transferred between the hot water storage tank 4 and the heat exchanger 2 in the hot water storage tank 4. And forced circulation by the forced circulation pump 3. Thereby, the water in the hot water storage tank 4 is indirectly heated by the heat exchanger 2. The temperature of the hot water in the hot water storage tank 4 is detected by a temperature sensor 23. The hot water discharged from the hot water storage tank 4 is supplied to the water supply from the branch pipe 22 via the first control unit 6 and the mixing device 5.
Is mixed to the required hot water temperature and supplied to the auxiliary heat source device 11 from the mixed hot water outlet 8.

In the auxiliary heat source unit 11, the supplied hot water enters through a hot water inlet 20, passes through a heat exchanger 13, and exits through a hot water outlet 21. Although not shown, the hot water outlet 21 is filled with a bathtub.
It is divided into hot water supply to the bathroom shower, hot water supply to the kitchen, hot water supply to the washroom, etc. (branch end pipe), and the user's desired temperature may differ for each hot water supply.

The method of controlling the temperature of the hot water in the solar water heater, particularly the solar water heater side, according to the present invention, includes automatic hot water filling of a bathtub that uses a large amount of hot water and other hot water supplies (for example, hot water supply to a bathroom shower, hot water supply to a kitchen). Hot water supply, hot water supply to the washroom, etc.). In addition, the communication means connected by the remote control cords 18 and 19 has a structure in which the solar water heater can recognize the hot water supply state on the auxiliary heat source.

In the solar water heater 1, in the automatic hot water filling of the bathtub, the outlet hot water temperature is controlled by the hot water mixing adjustment and control system using the desired hot water temperature (set temperature: TR) as a control temperature (FIG. 2). Here, the temperature of the hot water in the hot water storage tank (T
h), the case will be described separately below. (A) The hot water temperature (Th) of the hot water storage tank is the desired hot water temperature (T
In the case of the same or higher than R), the mixture is appropriately diluted with water by the mixing device 5 of the solar water heater 1,
The outlet hot water temperature is adjusted to TR and supplied to the auxiliary heat source unit side. (A ') The hot water temperature (Th) of the hot water storage tank is the desired hot water temperature (T
R) is lower than the water in the mixing device 5 of the solar water heater 1,
The water is supplied to the auxiliary heat source at the same hot water temperature.

For hot water supply other than bathtub automatic hot water filling, the outlet hot water temperature is adjusted to TR-α by the hot water mixing adjustment and control system (FIG. 2). As above, the temperature of the hot water in the hot water storage tank (T
h) will be described separately for each case. (B) The hot water temperature (Th) of the hot water storage tank is the desired hot water temperature (T
In the case of the same as or higher than R), the mixture is appropriately diluted with water by the mixing device 5 of the solar water heater 1,
The outlet hot water temperature is adjusted to TR-α and supplied to the auxiliary heat source. (B ') The hot water temperature (Th) of the hot water storage tank is the desired hot water temperature (T
When the temperature is lower than R) When the hot water temperature (Th) of the hot water storage tank is lower than TR-α, the hot water of the hot water storage tank is supplied without being diluted with water by the mixing device 5 at the hot water temperature of Th. (Th) is TR-
If the value is not less than α and less than TR, the mixture is diluted with water in the mixing device 5 and T
Adjust to R-α and supply to auxiliary heat source side.

A specific example will be further described. For example, the hot water temperature (Th) of the hot water storage tank 4 is 60 ° C., the desired tapping temperature and the set temperature (TR) are 42 ° C., α is 10 ° C., and β is 5 ° C.
The temperature control on the solar water heater side is such that, in the case of bathtub automatic hot water filling, hot and cold water is mixed by the mixing device 5 so that the hot water temperature becomes 42 ° C., and the 42 ° C. hot water is supplied to the auxiliary heat source device side. In the case of hot water supply other than bathtub automatic hot water filling, hot and cold water is mixed by the mixing device 5 so that the hot water temperature becomes TR-α, that is, 32 ° C.
The 32 ° C. hot water is supplied to the auxiliary heat source.

On the auxiliary heat source unit side, when the bathtub is automatically filled with hot water, the temperature of the hot water (42 ° C.) is TR-β, that is, 37 ° C.
Since the temperature is higher than ℃, hot water of 42 ℃ is supplied to the hot water supply destination without burning and heating. In the case of hot water supply other than bathtub automatic hot water filling, the hot water temperature (32
° C) is lower than TR-β, that is, 37 ° C, so that it is heated by the combustion / heating unit. The heated hot water is supplied (FIG. 3).

In another example, the hot water temperature (Th) of the hot water storage tank 4 is 35 ° C., the desired tapping temperature and the set temperature (TR) are 42 ° C. (Th <TR), α is 10 ° C., β is 5 ° C. I do. The temperature control on the solar water heater side is as follows. In the automatic hot water filling of the bathtub, the hot water is supplied to the auxiliary heat source side without mixing the hot and cold water with the mixing device 5, and the hot water temperature of the auxiliary heat source side (35 ° C.) Is T
Since it is lower than R-β, that is, lower than 37 ° C., it is heated by the combustion / heating unit. Hot water is supplied.

Here, if α is not set to a certain large value, the tapping temperature becomes higher than the set temperature TR when the auxiliary heat source unit is additionally heated.

Α is the lower limit of the heating capacity of the auxiliary heat source (H;
No.), the amount of hot and cold water on the solar water heater side (Q; L /
Min) and hot water temperature fluctuation offset (K; ° C), α =
Since it is given by (H × 25) ÷ Q + K, if a flow rate sensor is provided downstream of the mixing device 5 on the side of the solar water heater and Q is obtained, it can be almost correctly estimated. The solar water heater of FIG. 4 has a flow sensor 2 downstream of the mixing device 5 on the solar water heater side.
4 is provided. When using the auxiliary heat source (H is 2.5), the hot water supply (Q) to the auxiliary heat source is 10 liters per minute, and the remote control set temperature (TR) is 42 ° C, α
= (H × 25) ÷ Q + K, α = 6.25 + K ° C. Here, if K is 2 ° C., α = 8.25 ° C.

Although the energy saving effect is slightly reduced, the hot water supply temperature from the solar water heater to the auxiliary heat source can be set to a constant temperature (for example, 30 ° C.) in hot water supply other than bathtub automatic hot water filling. .

[0024]

According to the solar water heater, the auxiliary heat source device, and the solar water heater combining these, the following effects can be obtained. (1) When the bathtub is filled with a large amount of hot water, the operation of mixing and cooling (cooling) and reheating is not performed, thereby contributing to energy saving. (2) Even if hot water having a temperature lower than the set temperature (TR) and close to that temperature is supplied to the auxiliary heat source device, in hot water supply other than bathtub automatic hot water supply, TR-α is temporarily set on the solar water heater side.
, So that there is no fear of overheating and hot water exceeding the set temperature (TR). (3) Since the mixing of hot and cold water by the mixing device is suppressed as much as possible, the hot water in the tank heated and stored by using the solar heat can be effectively used without waste.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an example of a solar water heater, an auxiliary heat source device, and a solar water heater in which these are combined according to the present invention.

FIG. 2 is a flowchart of temperature control (solar water heater side) of a solar water heater according to the present invention.

FIG. 3 is a flowchart of temperature control (on the auxiliary heat source side) of the solar water heater according to the present invention.

FIG. 4 is a configuration diagram of a solar water heater according to another example of the present invention.

[Explanation of symbols]

 1: Solar water heater 2: Heat exchanger 3: Forced circulation pump 4: Hot water storage tank 5: Mixing device 6: First controller 8: Mixed hot water outlet 9: Water inlet 10: Heat collector 11: Auxiliary heat source device 12 : Combustion / heating unit 13: Heat exchanger 14: Second control unit 15: Remote control 16: Water flow detection device 17: Temperature sensor 18: Remote control code 19: Remote control code 20: Hot water inlet 21: Hot water outlet 22: Branch pipe 23 ： Temperature sensor 24 ： Flow sensor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor, Naotoshi Inoue 1250, Shimoedori, Shimodate-shi, Ibaraki Pref.Hitachi Kasei Kogyo Co., Ltd. Sei Kogyo Co., Ltd. Yuki Office

Claims (5)

[The claims] 1. A solar water heater to which an auxiliary heat source device is connected at an outlet side, wherein the solar water heater includes a hot water storage tank for storing hot water heated by solar heat, and a hot water temperature (Th) of the hot water storage tank. ), A mixing device for mixing the hot water from the hot water storage tank and the water supply from the branch pipe, a temperature sensor for detecting the hot water temperature after mixing, and a first control unit for controlling the operation of these components. In the bathtub automatic hot water filling, the hot water mixing adjustment and control system controls the outlet hot water temperature using TR as a control temperature, and in hot water supply other than the bathtub automatic hot water filling, the hot water mixing adjustment and control system , TR-α as a control temperature to control the outlet hot water temperature. Here, TR indicates a desired tapping temperature or a set temperature, and α indicates a positive predetermined temperature (° C.). 2. The solar water heater according to claim 1, wherein α is obtained by calculating (H × 25) ÷ Q + K. Here, H is the lower limit (number) of the heating capacity of the auxiliary heat source unit, Q is the amount of hot and cold water (L / min) on the solar water heater side, and K is the offset temperature (° C.) of the hot water temperature fluctuation. 3. An auxiliary heat source device connected to an outlet side of a solar water heater, wherein the auxiliary heat source device includes, in order from an inlet side thereof, a temperature sensor for detecting inlet-side hot water temperature, a heat exchanger, In addition to a branched end line, a combustion / heating unit for heating the heat exchanger and a control unit for controlling the operation of the apparatus are provided. If the temperature of the incoming hot water is lower than TR-β, combustion heating is performed. An auxiliary heat source device in which the unit is operated and the combustion heating unit is controlled to stop when the temperature is equal to or higher than TR-β. Where TR
Indicates a desired tapping temperature or a set temperature, and β indicates a positive predetermined temperature (° C.). 4. A solar water heater in which the solar water heater according to claim 1 or 2 and the auxiliary heat source device according to claim 3 are connected in order from the upstream. 5. The solar water heater according to claim 4, wherein a value equal to or smaller than α is selected as β.