JPH0749318Y2 - Control device for operating number of hot water boilers - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a control device that determines the number of hot water boilers that are installed in accordance with the load and controls the operation / stop of each hot water boiler. Is.

[Conventional technology]

In recent years, with the increase in efficiency and reliability of small hot water boilers, a so-called multi-can installation system has been adopted in which a plurality of small boilers are installed in place of a large hot water boiler.

The hot water boiler control method in this multi-can installation system is a method of manually selecting the number of hot water boilers to be operated according to the load, or a single temperature detector is used to start and stop all hot water boilers at once. The method of letting it was adopted. In the former, the hot water boiler needs to be operated and stopped, which is complicated, and efficient operation management cannot be performed unless the operator is skilled in the operation. In the latter case, all boilers are operated simultaneously by the instruction of the temperature signal of one temperature detector, so there is a drawback that the usage is inefficient at low load, and the operation and stop times are the same for all cans. Therefore, there is a drawback that the starting current becomes extremely large. Further, since the ignition occurs at the same time, there is a drawback that backfire of the ignition is likely to occur when using the collective chimney.

[Problems to be solved by the device]

In view of the above points, the present invention has an object to determine the number of operating machines according to the load situation and always operate the hot water boiler having a plurality of cans efficiently regardless of load fluctuations.

[Means for Solving the Problems]

In this invention, two or more hot water boilers are arranged side by side, the outlet pipe of each hot water boiler is connected to a load via a hot water supply pipe, a temperature detector is provided in the hot water supply pipe, and the temperature detected by this temperature detector t ₂
According to the temperature difference between the preset temperature t ₁ and the preset temperature t ₁ , a discriminator is provided for determining the required operating number of hot water boilers based on the operating number of hot water boilers set in advance for this temperature difference. When the number of operating units increases, the hot water boilers for the required number are operated at the rated combustion amount when the number of operating units increases in response to the signal from the It is characterized by the provision of a controller for controlling the number of units.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view of an embodiment in this invention. Two or more hot water boilers 1 are provided side by side, and the hot water outlet pipe 2 of each hot water boiler 1 is connected to the load 3 via the hot water supply pipe 4. The hot water outlet pipe 2 is provided with a check valve 8 for preventing backflow of hot water to the hot water boiler. A return pipe 9 connects the outlet side of the load 3 to the inlet of each hot water boiler. The return pipe 9 communicates with the makeup water tank 11 through the communication pipe 10, and the shortage of circulating water is supplied from the makeup water tank 11 through the communication pipe 10.

The hot water supply pipe 4 is provided with a temperature detector 5, and the temperature detector 5 is connected to a discriminator 6 by a signal line 12. The discriminator 6 stores a set temperature t ₁ for boiler operation control in advance, and the discriminator 6 detects the temperature t ₂ detected by the temperature detector 5.
And the set temperature t ₁ are calculated, the required operating number is determined based on the operating number of hot water boilers within a predetermined temperature difference range, and the signal of the required operating number is sent to the discriminator 6 and the signal. It transmits to the number-of-units controller 7 connected by the line.

The number controller 7 is connected to the operation part of each hot water boiler 1 by a signal line, and receives a signal from the discriminator 6 to operate the hot water boilers 1 by the number corresponding to the load through the signal line 12. It is transmitted to the hot water boiler 1 to control the operation of the hot water boiler 1. The number-of-units controller 7 has a starting order of the hot water boilers 1, and the hot water boilers 1 are sequentially started or stopped according to the preset starting order, and the required number of hot water boilers 1 are operated at the rated combustion amount. .

Next, the operation of the above embodiment will be described. When the hot water boiler 1 is operated, the circulation pump (not shown) provided in the hot water boiler is actuated to operate the hot water boiler 1 from the return pipe 9.
Water is supplied to the load 3. After being heated by the hot water boiler 1, the water is sent to the load 3 through the hot water outlet pipe 2 and the hot water supply pipe 4. The water that has released the retained heat under the load 3 is re-supplied to the hot water boiler 1 through the return pipe 9. If the amount of water supplied to the hot water boiler is insufficient, the makeup water is supplied from the makeup water tank 11.

In the above water circulation process, the temperature detector 5 provided in the hot water supply pipe 4 detects the temperature t ₂ of the hot water in the hot water supply pipe 4 and converts it into a temperature signal to the discriminator 6 through the signal line 12. Send. The discriminator 6 calculates a temperature difference between the detected temperature t ₂ and a preset temperature t ₁ preset in the discriminator, and compares the temperature difference with a predetermined temperature difference range and the number of operating units. ,
The required number of operating machines is determined, and a signal of the number of operating machines is transmitted to the number controller 7. The number-of-units controller 7 receives the signal regarding the number of operating units, operates the hot water boiler according to the starting order set in the number of units controller 7, or sequentially stops the hot water boiler 1 from the end of the starting order, and the discriminator 6 operates. Operate the specified number of hot water boilers at the rated combustion amount. By operating with the rated combustion amount, each hot water boiler can be operated in the optimum state (high-efficiency operation state).

That is, when the load increases from the capacity of the hot water boiler in operation and the temperature difference between the temperature t ₂ detected by the temperature detector 5 and the set temperature t ₁ becomes large, the number of hot water boilers in operation is set according to the set starting sequence. increase. On the other hand, when the load decreases due to the capacity of the hot water boiler and the temperature difference decreases, the hot water boilers are sequentially stopped from the end of the set starting sequence, and the number of operating machines is instructed by the discriminator 6. Further, when the capacity of the hot water boiler in operation and the load are balanced and the temperature difference becomes constant, the increase or decrease in the number of operating hot water boilers is stopped.

FIG. 2 is an explanatory diagram of a control example in the relationship between the temperature difference and the number of operating boilers in the present invention, in which the vertical axis represents the temperature difference between the temperature t ₂ detected by the temperature detector and the set temperature t ₁ , The horizontal axis shows the number of boilers operating. That is, when the temperature difference is less than Δt _{1, the} number of operating units is 0, when the temperature difference is between Δt ₁ and Δt _{2, the} number of operating units is 1, and the temperature difference is between Δt ₂ and Δt _3.
In the case of the interval, the number of operating machines is 2, and when the temperature difference is Δt ₃ or more, the number of operating machines is 3.

[Effect of device]

This invention is, as described above in detail, the temperature difference between the detected temperature t ₂ of the temperature sensor provided in the hot water supply pipe and the set temperature t _1,
Since the number of hot water boilers operating is discriminated and the hot water boilers are configured to operate at the rated combustion amount in accordance with the preset starting sequence, each hot water boiler can be operated in the optimum state (high-efficiency operation state). In addition, the hot water supply temperature can be made extremely stable against load fluctuations. Moreover, since the hot water boilers are sequentially started, the problem that the starting current is extremely increased and backfire at the time of ignition in the case of a collective chimney does not occur at all as in the conventional case.
Therefore, the present invention can provide a control device for always efficiently operating a plurality of hot water boilers regardless of load fluctuations.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of the present invention, and FIG.
FIG. 4 is an explanatory diagram of a control example thereof. 1 ... Hot water boiler, 2 ... Hot water outlet pipe 3 ... Load, 4 ... Hot water supply pipe 5 ... Temperature detector, 6 ... Discriminator 7 ... Unit controller, 8 ... Check valve 9 ... Return pipe, 10 …… Communication pipe 11 …… Makeup water tank, 12 …… Signal line

Claims (1)

[Scope of utility model registration request] 1. Two or more hot water boilers 1 are arranged side by side, an outlet pipe 2 of each hot water boiler 1 is connected to a load 3 via a hot water supply pipe 4, and a temperature detector 5 is provided on the hot water supply pipe 4. Depending on the temperature difference between the temperature t ₂ detected by the temperature detector 5 and the preset temperature t ₁ , the required number of hot water boilers is set based on the number of hot water boilers set in advance for this temperature difference. A discriminator 6 for determining is provided, and when a signal from the discriminator 6 is received and the number of operating units increases, the required number of hot water boilers are operated at the rated combustion amount in accordance with a preset starting sequence, A controller for operating the number of hot water boilers, which is provided with a unit number controller 7 for sequentially stopping the hot water boiler from the end of the starting sequence when the number decreases.