JPH02122128A - Hot water feeder - Google Patents

Abstract

PURPOSE:To reduce the cost of the control device of a hot water feeder by a method wherein when a difference in a demand heat load between two hot water feeder units is produced, the difference is detected, and based on the detecting value, the target feed hot water temperature of each heat circuit is varied and control is made so that the heat demand loads of the heat circuits are made equal to each other. CONSTITUTION:When water quality valves Mv1 and Mv2 of a hot water feeder unit U1 on the one side and a hot water feeder unit U2 on the other side are both not in a full opening state, demand heat loads HQ1 and HQ2 are regulated. When a demand heat load (HQ1=-DELTAHQ) obtained by adding a fine demand heat load DELTAHQ, set for preventing the occurrence of chattering, to the demand heat load HQ1 of the hot water feeder unit U1 on the one side is lower than the demand heat load HQ2 of the hot water feeder unit U2 on the other side, computation of HQ1=HQ2=HQT/2 is effected. Based on the computing value, a target feed hot water temperature ts1' of the hot water feeder unit U1 on the one side is computed as ts1'=HQT/2(xQ1)+tc, and a target feed hot water temperature ts2' of the hot water feeder unit U2 on the other side is computed as ts2'=HQT/(2XQ2)+tc. Thereafter, based on a combustion sequence by the target feed hot water temperatures ts1' and ts2', operation is continued.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a water heater in which a plurality of water heater units are arranged in parallel.

(b) Conventional technology In recent years, in order to improve comfort in daily life, it has become necessary not only to supply hot water to the kitchen or bathtub, but also to supply hot water to other hot springs such as showers and sinks. The amount of hot water required of water heaters is also inevitably increasing.

The ways to deal with this are: 1. Keep the water heater as one unit, but increase the size of the structure to have a large heat capacity; 2. Replace the conventional water heater with two without changing the structure of the water heater itself. It is conceivable to install the units in parallel inside the casing to have a large heat capacity.

However, in the former case, all the parts of the water heater consisting of a large number of parts must be remanufactured, resulting in a significant increase in manufacturing costs.

On the other hand, the latter does not have such problems and can use parts used in conventional water heaters as they are, so manufacturing costs can be reduced as much as possible.

Therefore, large-capacity water heaters have been developed and used exclusively of side-by-side type water heaters.

FIG. 3 shows the piping system in the water heater.

As shown in the figure, the water heater U is composed of a pair of water heater units (1, III) arranged in parallel inside a casing 50.

The water heater unit (example) tl includes a heat exchanger 51, a water supply pipe 53 connected to a water supply main pipe 52 to supply water to the heat exchanger 51, and a hot water heated and generated by the heat exchanger 51. A hot water supply pipe 55 that supplies hot water to the hot water main pipe 54 and a heat exchanger 5
1, and a burner 56 for heating.

In the above configuration, the main water supply pipe 52 includes a water supply temperature sensor Tc consisting of a thermistor, etc., and a total water flow sensor Fst.
is attached to the water supply pipe 53, and a water quantity sensor Ps,
is attached to the hot water supply pipe 55, and a hot water supply sensor Th,
and a water volume adjustment valve Mv+ are installed.

On the other hand, the other side water heater unit υ2 includes a heat exchanger 61, a water supply pipe 62 branched from the water supply pipe 53 to supply water to the heat exchanger 61, and a main water supply pipe that supplies hot water heated and generated by the heat exchanger 61. 54 and a burner 64 that heats the heat exchanger 61.

Further, in the above configuration, the hot water supply pipe 63 includes a hot water supply sensor T.
h2 and water volume adjustment valve ■ν2 are installed.

In normal operation, the water heater unit 7 and the other water heater unit Uz are operated with the same required heat load.

(c) Problems to be Solved by the Invention However, such conventional water heaters still have the following problems.

That is, - example water heater unit H, and the other side water heater unit) Il
If there is a deviation between the required heat load HQ+ and HQt for t,
Consideration must be given to complicated control of the amount of gas and air, and elimination of the influence of back pressure in the exhaust section.

Therefore, when such a deviation occurs, it is conceivable to promptly correct the deviation, but at present no effective measures have been taken from either a mechanical or control perspective.

An object of the present invention is to provide a water heater that can solve the above problems.

(d) Means for solving the problem The present invention detects the difference in the required heat load between the re-water heater units in a water heater in which two water heater units are installed side by side, The present invention relates to a water heater characterized by comprising a control means for changing the target hot water output temperature of each thermal circuit based on the detected value and performing control to equalize the required heat load of each thermal circuit.

(E) Actions and Effects As described above, if there is a difference in the required heat load between the reheating water heater units, the difference is detected and the target hot water output temperature of each heat circuit is changed based on the detected value, The required heat load of each thermal circuit can be equally controlled.

Therefore, it is possible to eliminate the need for complicated control of each of the gas amount and air amount, which is essential when there is a deviation between the required heat loads.
Furthermore, since the influence of back pressure in the exhaust section can be eliminated, water heater control can be simplified, and the cost of the water heater control device can be reduced.

Further, it is possible to prevent the required heat load of each water heater unit from becoming less than the minimum required heat load that causes fire extinguishment, and it is possible to reliably prevent fire extinguishment.

(f) Examples The present invention will be specifically described below based on examples shown in the attached drawings.

FIG. 1 shows the overall configuration of a water heater A according to the present invention, and in the figure, 10 is a casing;
houses a pair of water heater units u, 02 in parallel, and has an exhaust chamber 19 above it.

The water heater units O+ and Ut have substantially the same configuration, and each has a combustion gas supply path P-.
1 and a heat exchange channel P-2.

The combustion gas supply path P-1 includes a gas branch pipe 12 branched from the gas main pipe 11 and a solenoid valve 1 sequentially attached to the gas branch pipe 12.
3.14, a proportional valve 15, a plurality of gas jet nozzles 17 arranged in the combustion chamber IG, and an air supply fan 18.

The combustion chamber 16.16 communicates with an exhaust chamber 19 disposed in the upper part of the casing 10, and the exhaust chamber 19 communicates with an exhaust pipe (not shown).

On the other hand, the heat exchange channel P-2 includes a water supply branch pipe 21 branched from the water supply main pipe 20, a heat exchanger 22, and a hot water supply branch pipe 23 communicating with the hot water supply main pipe 24.

Further, in the above configuration, 30 and 31 are a main pipe side flow rate sensor and a main pipe side temperature sensor provided in the water main pipe 20, respectively.

On the other hand, 32 and 33 are one side flow rate sensor and one side temperature sensor respectively provided in the water supply branch pipe 21 and hot water supply branch pipe 23 of the water heater unit [11], and 35 is the other side water heater unit U.
This is the other side temperature sensor installed in the hot water supply branch pipe 23 of Z.

In addition, - example water heater unit U, and the other side water heater unit y 1
Water flow valves MVI-MV2 for adjusting the flow rate and performing one-sided operation are attached to the hot water supply branch pipes 23 and 23 of h, respectively.

Furthermore, in FIG. 1, 40 is a control device, and the control device 40 includes a microprocessor M as shown in the figure.
PU, input/output interface 41, 42, and ROM
and a memory 43 consisting of RAM.

In the above configuration, the old input interface includes the main flow rate sensor 30. Woodwind side temperature sensor 31. −
Side flow rate sensor 32. - side temperature sensor 33, other side temperature sensor 35, etc. are connected.

On the other hand, the output interface 42 includes a solenoid valve 1314.
, proportional valve 15, air supply fan 17 and water volume valve MV
+, Mv2 are connected.

The memory 43 also includes the various sensors 3031.
32, 33, 35, etc., and a drive signal from the controller 45 to drive the solenoid valve 13.14, the proportional valve 15, the air supply fan 17, the water volume valves Mvl, Mv2, etc. A sequence program is stored, and if the operating conditions or hot water supply conditions are changed during the process, the operating conditions etc. at the time of the change can be stored.

The normal hot water supply operation by the water heater A having the above configuration is performed as follows.

As shown in FIG. 1, when gas is supplied to the gas jet nozzle 17 via the combustion gas supply path P-1 in each of the water heater units U5 and U2 and ignited, the combustion heat of the gas causes the heat exchange flow path to The water flowing in P-2 becomes hot water, and the hot water is sent to the desired hot water outlet through the hot water supply wood pipe 24.

On the other hand, the combustion chamber 16.1 of each water heater unit U3, U, L
The exhaust gas generated by combustion in 6 flows into the exhaust chamber 19 provided at the upper part of the casing 10 through the exhaust gas inlet openings 36 and 37, and then flows into the exhaust stack and is then discharged to the outside. .

In the above configuration and operation, the present invention detects a tie when there is a difference in the required heat loads IQ, IQ, between both water heater units l'U+ and Uz, and each Water heater unit U1. [This relates to a water heater characterized by comprising a control means for changing the target hot water output temperature of the second thermal circuit and controlling the required heat loads HQ+ and HQ□ of each thermal circuit so as to be equal.

The present invention will be specifically described below with reference to the operation sequence shown in the flowchart of FIG.

First, the wood pipe side flow rate sensor 30 and the main pipe side temperature sensor 31
The main pipe side flow rate Qt and the main pipe side water supply temperature tc are respectively
The required heat load on the wood pipe side, that is, the total heat load 11Qt [1lQt = QtX(t,
-te)] is calculated (101).

Then, the required thermal load H(IT+t+) based on the detected value becomes the required thermal load 11Qa(tl
If it is larger than l (IOIY), calculate whether the required heat load IQ is smaller than the small required heat load (for example, No. 7), and if it is smaller, (102Y) - Example water heater unit I'u
Operation is performed in the + single combustion sequence (103).

On the other hand, if the required heat load HQT is larger than the above-mentioned small required heat load (102Y), the following step (1
04).

In addition, in this embodiment, if the required thermal load tlQT+t+ based on the detected value in step (10r) is smaller than the required thermal load 1 (Qt+t-n) based on the detected value immediately after (IOIN), the required thermal load H is smaller than the small required heat load (for example, No. 5), and if it is smaller (105Y), the - side water heater unit) operates in the independent combustion sequence of 11 (103).

On the other hand, if the required heat load IQ is larger than the above-mentioned small required heat load (105N), the following step (1
04).

Then, in step (104), the suikei valve MV of the − side water heater unit l'U+ and the other side water heater unit U2 is
If I and MV2 are both fully open (104Y),
Operation is performed based on the capacity limit control sequence (106
).

On the other hand, in step (104), the water flow valve Mv+ of the water heater unit U+ and the other water heater unit Uz,
If both Mv2 are not fully open (104Y), the required heat load +10. .

11Q, adjustments will be made.

That is, the required heat load of the − side water heater unit)L)Ill.

and the minute required heat load ΔH to prevent chattering.
If the sum with Q is larger than the required heat load HQ2 of the other water heater unit l'l12 (107N), - For example, from the required heat load HOI of the water heater unit u1 to the minute required heat load ΔHO provided to prevent chuckling. It is necessary to judge whether the value obtained by subtracting the value is smaller than the required heat load 110□ of the other water heater unit I'uz (10B), and if it is greater than <108N),
Operation will be performed based on the normal combustion sequence (109).

On the other hand, the required heat load (IQ, +ΔIQ), which is the addition of the minute required heat load ΔHO provided to prevent chattering to the required heat load IQ of the - side water heater unit Ul, is smaller than the required heat load 11Q2 of the other side water heater unit IJz. If (10
7Y), or the required heat load IQ of the - side water heater unit l"U+, minus the minute required heat load ΔIIQ provided to prevent chuckling, or the required heat 9 load (IIQl - 8HI
D) is smaller than the required heat load HQ2 of the other water heater unit U2 (]08Y), +10. =lIQ□-1
1Q, /2 is calculated (110).

Also, based on the same calculated value, - side water heater uni.

Target U1 hot water temperature ts+' is ts+□ = IQ
? Calculate as /(2XQ,) +te (111)
In addition, the target hot water temperature ts of the other water heater unit U2
2.t5□”1 (Qt / (2Xl]2) + tc
(112).

After that, operation continues based on the combustion sequence based on the same target hot water temperature ts+.+LsZ. (113)
.

As explained above, even if there is a deviation between the required heat loads HO Required heat load +10. , IQ2 are controlled to be equal, so complicated control of the essential gas amount and air amount is not necessary, and the influence of back pressure in the exhaust section can be eliminated. The overall control of the water heater A can be simplified, and the cost of the water heater control device can be reduced.

Furthermore, if the required heat load for the entire system does not fall under "small", each water heater unit U,,U.

It is possible to prevent the required heat load H[1,,)IQ2 from becoming less than the minimum required heat load that causes fire extinguishment, and it is possible to reliably prevent fire extinguishment.

In addition, in the above embodiment, the water heater unit IL and the other side water heater unit port 2 are integrally housed in a single casing 10, but they can also be housed in separate and independent casings. .

[Brief explanation of the drawing]

Fig. 1 is an explanatory conceptual diagram of the water heater according to the present invention;
The figure is a flowchart showing the operation sequence of the water heater, and FIG. 3 is a diagram illustrating the conceptual structure of a conventional water heater unit. In the diagram, A: An example of a water heater. Water heater unit. Other side. Water heater unit. Casing. Combustion chamber. Gas jet nozzle. Air supply fan. Exhaust chamber.

Claims (1)

[Claims] 1. In a water heater with two water heater units installed side by side,
If there is a difference in the required heat load between the two water heater units, the difference is detected and the target hot water output temperature of each heat circuit is changed based on the detected value, thereby making the required heat load of each heat circuit equal. A water heater characterized by comprising a control means for performing the following.