JP3166459B2 - Water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply apparatus, and more particularly, to a hot water supply apparatus having an instantaneous heat exchanger, in which hot water discharged through the heat exchanger and water from a bypass pipe are mixed and adjusted by a mixing controller. The present invention relates to a hot water supply apparatus that supplies hot water at a set hot water supply temperature and that controls an excessive flow rate that hinders temperature adjustment by an overflow prevention regulator provided in a hot water supply pipe.

[0002]

2. Description of the Related Art There has been conventionally provided a hot water supply apparatus having an instantaneous heat exchanger, a bypass pipe, a mixing regulator, and an overflow prevention regulator. The schematic configuration will be described with reference to FIG. The apparatus includes an instantaneous heat exchanger 10, a water inlet pipe 11 for sending water to the heat exchanger 10, a hot water pipe 12 for hot water heated by the heat exchanger 10, and a hot water pipe 12 from the water inlet pipe 11.
A bypass pipe 13 for bypassing the water, a mixing controller 14 for mixing and adjusting the water from the bypass pipe 13 and the hot water from the tapping pipe 12, and a hot water supply connected downstream of the mixing controller 14. It has a pipe 15 and an overflow prevention adjuster 16 provided in the hot water supply pipe 15. The instantaneous heat exchanger 10 is heated by a burner 17 such as an oil burner. 21 is a heat exchange flow rate sensor, 22 is an incoming water temperature sensor, 23 is a hot water temperature sensor, and 24 is a hot water supply temperature sensor. Hot water temperature is set,
When the hot water supply curl (not shown) is opened and the operation is started, hot water is discharged from the water inlet pipe 11 through the heat exchanger 10 to the hot water outlet pipe 12, and the hot water from the hot water outlet pipe 12 is further discharged from the bypass pipe 13. The water is appropriately adjusted by the mixing controller 14, adjusted to the set hot water supply temperature, and flows to the hot water supply pipe 15. The mixing controller 14 turns on and off the hot water temperature caused by turning the burner 17 on and off, by changing and adjusting the mixing amount of water from the bypass pipe 13, to a uniform hot water supply temperature. , And serves to send water to the hot water supply pipe 15. Further, the overflow prevention regulator 16 plays a role of preventing a temperature decrease due to overflow by reducing the total water amount when the hot water flowing through the hot water supply pipe 15 does not reach the set hot water supply temperature. .

[0003]

However, in the above hot water supply apparatus, when the hot water supply temperature does not necessarily reach the set hot water supply temperature, it is necessary to reduce an excessive flow rate. Fluctuates,
It is difficult to calculate the total flow rate at that time, so that there is a disadvantage that the flow rate to be throttled by the overflow prevention regulator 16 cannot be calculated accurately. That is, the total flow rate is determined by the flow rate detected by the heat exchange flow rate sensor 21 and the mixing controller 14.
If the distribution rate of the mixing controller 14 fluctuates frequently, it becomes difficult to calculate the total flow rate, and thus it is difficult to calculate the total heat output at that time. It becomes difficult to compare the required amount of heat with the hot water supply temperature, and as a result, it becomes difficult to calculate the flow rate to be reduced.

Therefore, the present invention solves the above-mentioned disadvantages of the conventional hot water supply apparatus, and when the hot water supply temperature does not reach the set hot water supply temperature, the overflow prevention controller 16 reduces the flow rate and adjusts the flow rate to the set hot water supply temperature. It is another object of the present invention to provide a hot water supply apparatus capable of accurately calculating a flow rate to be throttled, and thereby reliably raising the temperature to a set hot water supply temperature.

[0005]

In order to achieve the above object, a hot water supply apparatus of the present invention comprises an instantaneous heat exchanger, a water inlet pipe for sending water to the heat exchanger, and hot water heated by the heat exchanger. A tapping pipe for tapping water, a bypass pipe for bypassing water from the inlet pipe to the tapping pipe, a mixing controller for mixing and adjusting the water from the bypass pipe and the hot water from the tapping pipe, and the mixing control A hot water supply pipe connected downstream of the vessel,
A hot water supply device having an overflow prevention adjuster provided in the hot water supply pipe, wherein when a necessary condition for flow rate adjustment by the overflow prevention adjuster is satisfied during the hot water supply operation, an adjustment position by the mixing adjuster is provided. Is fixed at a fixed position for a fixed time, during which the throttle flow rate is calculated by the overflow prevention regulator.

[0006]

According to the above-mentioned feature of the present invention, when the condition for operating the over-spill prevention regulator, that is, the necessary condition for the flow rate adjustment by the over-spill prevention regulator is satisfied, the adjustment position by the mixing controller is fixed. Since the time is fixed at a fixed position, the total flow rate can be accurately and reliably calculated during that time, and thus the total heat amount, which is the total output at that time,
The flow rate can be calculated from the hot water supply temperature, the incoming water temperature, and the total flow rate, and the flow rate to be reduced (reduced) to make the hot water supply temperature the set hot water supply temperature can be accurately and reliably calculated from the total heat quantity. By actually reducing the calculated flow rate to be reduced (reduced) by the overflow prevention controller, it is possible to secure hot water supply at the desired set hot water supply temperature. The necessary condition for the flow rate adjustment by the overflow prevention regulator may be, for example, a condition in which the burner is burned at the maximum capacity and the hot water supply temperature never reaches the set hot water supply temperature.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.
FIG. 1 is an overall configuration diagram of a hot water supply apparatus according to the present invention, and FIG. 2 is a flowchart illustrating an operation control operation of the embodiment apparatus.

The entire configuration shown in FIG. 1 is the same as the configuration already described in the section of the prior art, so that the description will be omitted. However, the controller 30 is newly specified. The controller 30 controls the entire apparatus, and includes a heat exchange flow sensor 21, an incoming water temperature sensor 22, an outgoing water temperature sensor 23, and a hot water supply temperature sensor 2.
4.Input the information from other sensors, and also input the set hot water temperature information by a remote controller not shown, perform necessary calculations, and input necessary commands to the mixing controller 14, the overflow prevention controller 16, Send to burner 17, etc.

The hot water supply control operation by the controller 30 will be described with reference to FIG. When the heat exchange flow sensor 21 detects the minimum operating water amount (MOQ) or more by opening a hot water supply curl (not shown) (Yes in S1), the controller 30 firstly sets the hot water supply temperature set by the remote controller or the like. From the input water temperature detected by the input water temperature sensor 22 and the total flow rate calculated from the flow rate detected by the heat exchange flow rate sensor 21 and the initial distribution position of the mixing controller 14, a required combustion heat quantity Q is calculated. The fuel supply amount such as petroleum and the blowing amount are determined based on the necessary combustion heat amount Q,
The combustion is started by the feed forward control (S2).

Then, normally (steps S5 and S6 to be described later)
After the start of the combustion operation, the controller 30 controls the combustion of the burner 17 by proportional control while comparing the hot water temperature detected by the hot water temperature sensor 24 with the set hot water temperature. Then, feedback control is performed so that the hot water supply temperature approaches the set hot water supply temperature (S3). Then, when the flow rate becomes less than the minimum working water amount or the operation switch is turned off by closing the hot water supply curan (Yes in S4), the controller 30 stops the combustion (S5).

On the other hand, during the combustion operation, the controller
30 determines whether or not the burner 17 is burning with the maximum combustion heat quantity that is the maximum output (S6). If yes, it is further determined whether the hot water supply temperature detected by the hot water supply temperature sensor 24 is lower than the set hot water supply temperature by a certain temperature a, for example, several degrees such as 4 ° C. (hot water supply temperature <set hot water supply temperature−a) ( S7). If yes, it is determined whether or not the state continues for a predetermined time b, for example, several tens of seconds such as 20 seconds (S8). When the predetermined time b has elapsed in the above state (Yes in S8), the controller 30 controls the mixing controller 14 to adjust the distribution position to fully open the tapping pipe 12 side and fully close the bypass pipe 13 side. Then, it is fixed at that position (S9). That is, the controller 30 drives the mixing controller so that only the hot water from the tapping pipe 12 flows to the hot water supply pipe 15 side. After fixing the mixing controller 14 at the fully open position on the tapping pipe 12 side (fully closed on the bypass pipe 13 side), after waiting for a certain time c, for example, about several seconds (Yes in S10), the controller 30 prevents overflow. The controller 16 calculates the flow rate to be reduced (S12), issues a drive command to the overflow prevention regulator 16, and reduces the flow rate (S13). Before the elapse of the predetermined time c, the condition in step S6 or step S7
If the condition in is not satisfied, the state returns to the original state (S1
1).

The calculation of the flow rate to be throttled by the controller 30 is performed as follows. First, the current flow rate detected by the heat exchange flow rate sensor 21 (this time is the total flow rate), the current hot water supply temperature detected by the hot water supply temperature sensor 24, and the current incoming water temperature detected by the incoming water temperature sensor 22 Then, the current output (current amount of combustion heat) is calculated by the following equation. Current combustion heat quantity = current flow rate × (current hot water supply temperature−current water supply temperature) Further, a target flow rate is calculated from the calculated current combustion heat quantity and the set hot water supply temperature by the following equation. Target flow rate = current combustion heat quantity ÷ set hot water supply temperature Then, by subtracting the target flow rate from the current flow rate, a flow rate to be reduced by the overflow prevention controller 16 is obtained. Flow to be throttled = Current flow-Target flow

As described above, when the flow rate to be throttled is calculated, the controller 30 drives the overflow prevention regulator 16 while monitoring the heat exchange flow rate sensor 21 to actually reduce the flow rate to be throttled. Thereafter, the fixed state of the mixing controller 14 is released.

[0014]

According to the present invention, there is provided the above construction.
According to the hot water supply apparatus described in the above, when the necessary condition of the flow rate adjustment by the overflow prevention regulator is satisfied during the hot water supply operation, the adjustment position by the mixing controller is fixed at a fixed position for a fixed time, and the excess Since the throttle flow rate is calculated by the outflow prevention controller, the total flow rate can be calculated accurately and reliably during that time. Therefore, when the hot water supply temperature does not reach the set hot water supply temperature, the flow rate to be reduced can be accurately reduced, the temperature can be reliably raised to the set hot water supply temperature, and the hot water supply at the initial set hot water supply temperature can be secured.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a hot water supply device of the present invention.

FIG. 2 is a flowchart illustrating an operation of the embodiment.

[Explanation of symbols]

 10 Instantaneous heat exchanger 11 Inlet pipe 12 Outlet pipe 13 Bypass pipe 14 Mixing regulator 15 Hot water supply pipe 16 Overflow prevention regulator 17 Burner 21 Heat exchange flow sensor 22 Inlet temperature sensor 23 Outlet temperature sensor 24 Hot water temperature sensor 30 Controller

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F24H 1/10 302

Claims (1)

(57) [Claims] 1. An instantaneous heat exchanger, a water inlet pipe for sending water to the heat exchanger, a hot water pipe for hot water heated by the heat exchanger, and a water bypass from the water inlet pipe to the hot water pipe. Pipe, a mixing regulator for mixing and adjusting the water from the bypass pipe and the hot water from the tapping pipe, a hot water pipe connected downstream of the mixing regulator, and a heater provided in the hot water pipe. A hot water supply device having an outflow prevention adjuster, wherein when a necessary condition of flow rate adjustment by the over-outflow prevention adjuster is satisfied during the hot water supply operation, the adjustment position by the mixing adjuster is set to a certain position for a certain time. Fixed,
In the meantime, the hot water supply device is configured to calculate a throttle flow rate by the overflow prevention regulator.