JPH0759989B2 - Water heater - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hot water supply device including a general hot water supply passage connected to a general hot water supply tap and a bath hot water supply passage connected to a bathtub.

(Prior Art) In a conventional water heater of this type, for example, as shown in Japanese Utility Model Laid-Open No. 61-3353, a water passage on the upstream side of a heat exchanger and a general water passage are connected by a bypass passage. Along with the water flow control valve installed in the bypass passage, when the general hot water tap is opened during high temperature hot water supply from the bath hot water supply passage to the bathtub, the bypass water is mixed in the general hot water supply passage and suddenly hot water is discharged. To prevent danger, the flow rate of the bypass water is controlled by the water flow control valve,
I was trying to get the mixed water at the desired temperature.

(Problems to be solved by the invention) In this type of hot water supply device, when general hot water is used simultaneously during high temperature hot water supply from the bath hot water supply passage, the general hot water supply passage has a smaller flow resistance than the bath hot water supply passage. In this case, most of the high-temperature hot water from the heat exchanger flows into the general hot water supply passage, and in the case of a water heater with a particularly high capacity, a large amount of high-temperature hot water is supplied, so even if bypass water is mixed from the bypass passage, There is a problem that hot water that is considerably hotter than the set temperature of hot water is discharged.

Therefore, it is possible to provide a flow control valve in the general hot water supply passage and throttle the flow control valve in advance so that the amount of high-temperature hot water supplied to the general hot water supply passage will be a small flow rate during high temperature hot water supply from the bath hot water supply passage. Conceivable.

However, in that case, there arises a problem that the flow rate of the mixed hot water obtained from the general hot water supply passage becomes small.

The present invention solves the above-mentioned problems, and even if general hot water is simultaneously used during high-temperature hot water supply from the bath hot water supply, hot water higher than the set temperature will not be abruptly discharged, and the set temperature will be set from the general hot water supply passage. It is an object of the present invention to provide a hot water supply device capable of obtaining the maximum amount of mixed hot water within a controllable range.

(Means for Solving the Problems) In order to achieve the above object, the hot water supply device of the present invention has the following configuration. That is, the hot water supply passage on the downstream side of the heat exchanger is branched into the general hot water supply passage and the bath hot water supply passage, and the bypass passage branched from the water supply passage on the upstream side of the heat exchanger is connected to the general hot water supply passage. The first flow rate control valve, the second hot water supply passage upstream of the connection with the bypass passage, the second flow control valve, the general hot water supply passage downstream of the connection with the bypass passage, a mixed hot water temperature sensor, The first flow rate control valve is controlled based on the hot water temperature, and the second flow rate control valve is controlled to a predetermined small opening position during high temperature hot water supply from the bath hot water supply passage to detect simultaneous use of the general hot water supply passage. Then, the second flow control valve is controlled in the opening direction until either the first flow control valve or the second flow control valve reaches the maximum opening position.

(Operation) When high-temperature hot water supply from the bath hot water supply passage to the bathtub is started, the second flow rate control valve is made to stand by at a predetermined small opening (for example, minimum opening) position, so that the general hot water supply is performed when the general hot water tap is opened. The hot water flowing through the passage has a small flow rate, and water is mixed from the bypass passage, so that the temperature of the mixed hot water initially becomes a safe low temperature. When this simultaneous use of general hot water is detected, the first flow rate control valve controls the amount of bypass water based on the mixed hot water temperature, while the second flow rate control valve is controlled to open. As a result, as the second flow rate control valve opens, the first flow rate control valve also opens, and when either one reaches the maximum opening position, the amount of mixed hot water is within the controllable range to the set temperature. It will be the maximum.

(Embodiment) FIG. 1 is a water channel configuration diagram showing an embodiment of the present invention, in which a general hot water supply passage 3 and a bath hot water supply passage 4 are branched from a downstream of a hot water outlet temperature sensor 2 provided at an outlet of a heat exchanger 1. They are connected to a general hot water tap 5 and a bathtub 6, respectively.

A water supply amount sensor 8 for detecting the amount of water entering the heat exchanger 1 and a water temperature sensor 9 are provided in the water supply passage 7 on the upstream side of the heat exchanger 1, and a bypass passage 10 branched from the upstream side is provided for a general hot water supply passage. Connected to 3. A bypass water amount sensor 11 and a first flow control valve 12 are provided in the bypass passage 10, and a second flow control valve 13 is provided in the general hot water supply passage 3 on the upstream side of the connection portion with the bypass passage 10.
A check valve 14 is provided, and a mixed hot water temperature sensor 15 is provided on the downstream side of the connecting portion.

The bath hot water supply passage 4 is provided with a solenoid valve 16, a bath flow sensor 17, a vacuum breaker 18, and a third flow control valve 19.
Reference numeral 20 denotes a controller equipped with a microcomputer, which inputs signals from the water input amount sensor 8, the bypass water amount sensor 11, the bath flow rate sensor 17, the mixed hot water temperature sensor 15, etc., and the first and second flow rate control valves 12, 13 etc. Control signal is output to.
The first and second flow rate sensors 12, 13 are provided with drive motors so that the minimum and maximum opening positions of the valves can be detected by position detecting means such as limit switches.

If not illustrated remote control to command the hot water heater to the tub 6, the electromagnetic valve 16 is opened, the hot water temperature T _H of the heat exchanger 1
Is controlled to a predetermined high temperature (for example, 80 ° C.), the combustion amount of a burner (not shown) is controlled, and in this embodiment, the bath hot water supply passage 4
The high-temperature hot water flowing through is controlled to a predetermined flow rate (for example, 5 l / min) by the third flow rate control valve 19 (step S1 in FIG. 2).

Then, the second flow control valve 13 is controlled to the minimum opening position, and the first flow control valve 12 is controlled to the maximum opening position (step S2).

When hot water is supplied to the hot water supply sensor 8, the bypass water flow sensor 11, and the bath flow sensor 17 are detected as Q ₁ , Q ₂ , and Q ₃ , respectively, Q ₁ + Q ₂ −Q ₃ is constant (for example, 2.5 l). / min), the opening of the general hot water tap 5 is detected (step S3), and the second
The flow control valve 13 is driven in the opening direction. That is, in this embodiment, at this time, the second flow control valve 13 is connected to the water input sensor 8
It detected flow Q is controlled based on _1, to control the target flow rate Q _S in the direction of opening the valve only as many flow latest detected flow Q is from ₁ flow rate α of. On the other hand, in the first flow control valve 12, the mixed hot water temperature T _M detected by the mixed hot water temperature sensor 15 is the set temperature T _{MS of the} general hot water supply.
However, in the present embodiment, in consideration of the control delay, the mixed hot water temperature T _M is controlled to be a temperature lower than the set temperature T _MS by a certain temperature β (step S4). ).

In this way, when the hot water supply amount is increased while controlling the mixed hot water temperature T _M to a temperature substantially equal to the set temperature T _MS , and the first flow control valve 12 or the second flow control valve 13 reaches the maximum opening position ( Steps S5 and S6), α and β in step S4 are deleted, the second flow rate control valve 13 becomes Q _S = Q _1, and the first flow rate control valve 12 becomes T _M = T _MS. Are controlled as described above to return to the normal control state (step S7). In this state, the maximum amount of the mixed hot water having the set temperature T _MS can be obtained from the general hot water supply passage 3.

(Effects of the Invention) The hot water supply device of the present invention has the following excellent effects. That is, when the general hot water tap is opened during high-temperature hot water supply from the bath hot water supply path, hot water above the set temperature will not be discharged, and the maximum amount of mixed hot water at the set temperature will be output from the general hot water supply path. It is possible to make the most of the hot water supply capacity.

[Brief description of drawings]

FIG. 1 is a water channel configuration diagram showing an embodiment of the present invention, and FIG. 2 is a control flow chart thereof. 1 …… Heat exchanger 3 …… General hot water supply passage 4 …… Bath hot water supply passage 7 …… Hot water supply passage 10 …… Bypass passage 12 …… First flow control valve 13 …… Second flow control valve 15 …… Mixed Hot water temperature sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Ikeda 32 Akashi-cho, Chuo-ku, Kobe-shi, Hyogo In stock company Noritsu (72) Inventor Hidekazu Fukui 32 Akashi-cho, Chuo-ku, Kobe, Hyogo Stock company Noritsu (72) Inventor Haruhiko Tamada 32 No. Akashi-cho, Chuo-ku, Kobe-shi, Hyogo Incorporated Noritsu (72) Inventor Tadahiko Oshio No. 32 Akashi-cho, Chuo-ku, Kobe-shi, Hyogo (72) Inventor Yoichiro Murakami 32nd Akashi-cho, Chuo-ku, Kobe-shi, Hyogo Masayoshi Iwamoto Examiner, Noritsu Co., Ltd.

Claims (1)

[Claims] 1. A hot water supply passage downstream of a heat exchanger is branched into a general hot water supply passage and a bath hot water supply passage, and a bypass passage branched from a water supply passage upstream of the heat exchanger is connected to the general hot water supply passage. , A first flow rate control valve in the bypass passage, a second flow control valve in the general hot water supply passage upstream of the connection portion with the bypass passage, and a mixed hot water temperature sensor in the general hot water supply passage downstream of the connection portion with the bypass passage Is provided to control the first flow rate control valve on the basis of the mixed hot water temperature, and the second flow rate control valve is controlled to a predetermined small opening position during high temperature hot water supply from the bath hot water supply passage to control the general hot water supply passage. When detecting simultaneous use, the second flow control valve is controlled in the opening direction until either one of the first and second flow control valves reaches the maximum opening position.