JP3119550B2 - Water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method in which a plurality of water heaters are connected in parallel, a required total heat amount is calculated from an incoming water temperature, a set temperature and a total amount of incoming water, and the required total heat amount and the heat capacity of each water heater are calculated. The present invention relates to a hot water supply device for determining the number of operating units.

[0002]

2. Description of the Related Art A conventional hot water supply apparatus has a remote controller for inputting a set temperature by a user, and a unit controller for connecting the remote controller and individually controlling the operation of each water heater.
A plurality of hot water heaters are connected in parallel, hot water from each of them is discharged in common to the hot water curan side, the required total heat quantity is calculated from the incoming water temperature, the set temperature and the total amount of incoming water, and the required total heat quantity and each hot water supply The number of operating units is determined from the heat capacity.

[0003]

However, in a water heater that determines the number of operating water heaters based on the total amount of heat required and the heat capacity of each water heater, first, the amount of water entering the water heater whose operation has been determined is determined by the amount of water in the combustion device. When the amount of water for operating the water flow switch is less than the amount of water to operate, the water heater may not operate normally, or secondly, when the flow rate is increased and the flow velocity is increased, erosion may occur in the heat exchanger and the tapping pipe.

[0004]

According to a first aspect of the present invention, there is provided a water heater in which a plurality of water heaters are connected in parallel, and a required total heat amount is determined based on an incoming water temperature, a set temperature, and an amount of incoming water. In the water heater that determines the number of units to be operated from the required total heat quantity and the heat capacity of each water heater, the value determined by the minimum flow rate of each water heater from the total amount of incoming water is the maximum number of operating units, and each hot water supply is determined from the total amount of incoming water. Set the value determined by the maximum flow rate of the unit as the minimum operating number, and if the operating number exceeds the maximum operating number, change the maximum operating number to the operating number, and if the operating number is less than the minimum operating number, Changes the minimum operating number to the operating number. In addition,
In the invention according to claim 2, the number control device performs
More individual differences due to different types of water heaters, heat capacity and pressure loss
Enter and set in advance and add the heat capacity for each unit.
Hot water supply system that compares the sum of
You.

[0005]

In the hot water supply apparatus of the present invention having the above configuration, the number of operating units determined from the required total heat quantity does not exceed the maximum number of operating units determined from the minimum flow rate. To prevent
Since there is no case where the number of operation units is less than the minimum operation number obtained from the maximum flow rate, erosion of the heat exchanger and the like due to flowing water can be prevented.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the hot water supply apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a hot water supply apparatus. The hot water supply apparatus 1 includes a plurality of n hot water heaters 2, 2,.
And a water supply pipe 3 of a water pipe connecting these water heaters in parallel.
And a hot water outlet pipe 4 for commonly supplying hot water to the hot water curl side, and a hot water heater 2, 2,. The number of operating water heaters that start operating according to the situation is summarized, and the number control device 5 that controls the tap water temperature and the amount of tap water is set, and the setting status of the tap water temperature and the like that is connected to the number control device 5 is described. Remote controls 6 and 6 for inputting. In the water heater 2, there is provided a burner controller 20 for controlling the hot water supply operation of each water heater 2 according to a command from the number control device 5. The burner controller 20 has a temperature sensor 21 for measuring the incoming water temperature of the supply water, a water amount sensor 22 for detecting the amount of hot water, and an on-off valve 2 for opening and closing the flow path.
3 and a flow control valve 25 for adjusting the amount of hot water are connected.

The number control device 5 instructs each water heater to control the opening / closing valve 23 of each of the water heaters 2, 2,... Which controls the number of operating water heaters, manages the set temperature from the remote controller 6, and controls each water heater. Send. Burner controller 2 for each water heater
0 controls the on-off valve 23 and sets the number control device 5
Of the gas supply unit and the air supply unit in the water heater from the set temperature, temperature sensor 21, water amount sensor 22, combustion proportional control valve 24, and a combustion sensor for detecting the combustion state above the burner. Performs control and the like. Reference numeral 26 denotes a main solenoid valve for opening and closing the gas passage.

Next, the operation of the number control device 5 for determining the number of operating water heaters will be described with reference to FIG. 2 showing a flowchart. First, when the number control device 5 is turned on, individual data of the water heater 2 is input in step S1. This is set in advance when there is an individual difference due to the type of water heater, heat capacity and pressure loss, and only one time is required for the same water heater. Then, the input water temperature measured by the temperature sensor 21 in step S2, and the setting state of the hot water temperature and the like from the remote controller 6 in step S3,
Further, the water input amount detected by the water amount sensor 22 in step S4 is input to the number control device 5. The required total heat amount is calculated in step S5 from the incoming water temperature, the set temperature, and the total amount of incoming water, and the number of operating water heaters is calculated in step S6 based on the heat capacity of the water heater. This calculation method is a method of dividing the required total heat amount by the heat capacity of the same hot water heater, or the sum of the heat capacity and the required heat amount by summing the heat capacity for each number of water heaters of different types. There is a method to find by comparing the size. Next, by dividing the total amount of water input in step S4 by the minimum water amount and the maximum water amount of the water heater, step S4 is performed.
The maximum operating number is obtained in step S7 and the minimum operating number is obtained in step S8. Then, the operation number assumed in step S9 is compared with the minimum operation number, and if the operation number is smaller,
In step 10, the minimum operating number is changed to the operating number. Conversely, if the number of operating units is larger, step 1
The number of operating vehicles assumed in 1 is compared with the maximum number of operating vehicles. If the operating number is larger than the maximum operating number, step S
At 12, the maximum number of operating units is changed to the number of operating units.
Conversely, if the operating number is smaller, the hot water supply apparatus is started in step S13 with the operating number unchanged and the operating number already changed in steps S10 and S12 determined similarly.

FIG. 3 is a graph showing the relationship between the number of operating units and the flow rate according to this control process. The number of operating units is always determined between the line A with the minimum flow and the line B with the maximum flow. In other words, in the case of an arbitrary incoming water amount Lex., When the number of operating vehicles in step S6 is assumed to be one, the number of operating vehicles is changed to two, which is the minimum number of operating vehicles. Change to 5 units.

A water flow sensor 22 is provided in each water heater 2 and integrated by the number control device 5 to obtain the total water input of the entire water heater. The total water flow is set at a position before the water pipe is branched to each water heater. If a sensor is attached and the number of the water amount sensors is reduced, the frequency of occurrence of a failure can be reduced. Further, in a water heater in which the burner burns a small amount, the temperature of the hot water drops before reaching the maximum water flow. Therefore, it is desirable to set the water flow at the time of maximum combustion to the maximum water flow. Thus, it is possible to prevent the temperature of the hot water from lowering due to overload.

[0011]

As described in detail above, according to the present invention, the number of operating units determined from the required total heat quantity does not exceed the maximum operating number determined from the minimum flow rate. Since it is possible to prevent the open igniter from extinguishing the fire and to keep the minimum number of operating units required from the maximum flow rate, it is possible to prevent erosion of tubes such as a heat exchanger by running water.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a hot water supply apparatus as one embodiment.

FIG. 2 is a flowchart showing the operation of the hot water supply apparatus as one embodiment.

FIG. 3 is an explanatory diagram showing in a graph the relationship between the number of operating units and the flow rate in the hot water supply apparatus as one embodiment.

[Explanation of symbols]

1. Hot water supply device, 2. Hot water supply device, 3. Water supply pipe, 4.
Hot water supply pipe, 5 ... Number control device, 6 ... Remote control, 21.
・ Temperature sensor, 22 ・ ・ Water amount sensor, 23 ・ ・ On-off valve,
24 ... Proportional control valve.

Claims (2)

(57) [Claims] 1. A plurality of water heaters are connected in parallel to each other,
The required total heat quantity is calculated from the set temperature and the total amount of incoming water, and the hot water supply device equipped with a unit control device that determines the number of operation units from the required total heat quantity and the heat capacity of each water heater. Set the value to be determined as the maximum number of operating units, and the value determined from the maximum flow rate of each water heater based on the total amount of water input as the minimum number of operating units.If the number of operating units exceeds the maximum number of operating units, set the maximum operating number to the number of operating units And if the number of operating units is less than the minimum number of operating units, the minimum operating number is changed to the number of operating units. 2. The number control device according to claim 1, wherein
Depending on the type of water heater, individual type, heat capacity and pressure loss
Enter the body difference, set it in advance, and add the heat capacity for each unit.
Hot water supply unit that compares the total amount of heat and the required amount of heat
Place.