JPH0252949A - Hot-water supplier with bypass water channel - Google Patents

Abstract

PURPOSE:To obtain stable temperature of discharged hot-water without directly discharging the hot-water that is made subsequently by providing control means by which, in the case in which the volume of hot-water made subsequently is larger than a specified volume, a solenoid valve is in the open state for a specified time when supplied hot-water is used again. CONSTITUTION:A water inlet 11 communicates with a branch point 12, and at the branch point 12 a channel to pass water is branched to a water channel 13 and bypass water channel 14. The water channel 13 on one side passes through a heat exchanger 15 to supply hot water and the other water channel 14 passes through a solenoid valve 16 and they each communicate with a merging point 17. This merging point 17 communicates with a hot-water outlet 19 via a thermistor 18 for measuring temperature of mixing. When, after the use of a hot-water supplier 21 is temporarily stopped, it is used again, the volume of the hot-water made subsequently in the heat exchanger 15 for hot-water supply is calculated, and when the volume of the hot-water made subsequently is over 0.5, the solenoid valve 16 in the bypass water channel 14 is opened for a specified time during the heat exchanger for supplying hot-water is reused and the high temperature water made subsequently in the heat exchanger 15 for supplying hot-water is mixed with the water in the bypass water channel 14 at the merging point 17 to cool the hot-water. In this constitution hot-water is not discharged directly from the hot-water outlet 19.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a water heater with a bypass water channel.

BACKGROUND OF THE INVENTION Conventionally, in this type of water heater with a bypass conduit, a bypass conduit 4 is connected in parallel to a conduit 3 which passes through a water inlet pipe 1 and a heat exchanger 2 for hot water supply, as shown in FIG. A motor-driven water flow proportional valve 5 is provided at the connection point serving as the merging point. A thermistor 6 is provided behind the merging point and communicates with the tap water pipe 7. 5a is a motor, and 8 is a control section.

Due to the above-mentioned barrel formation, heavy water, the operation of which will be explained below, passes through the water inlet pipe 1 and flows at a branch point 9 into a water channel 3 passing through a hot water supply heat exchanger 2 and a bypass water channel 4. At this time,
The water in the hot water supply heat exchanger 2 is heated by a burner 10, merges at a junction where a motor-driven water flow proportional valve 5 is provided, and is supplied from a hot water outlet pipe 7. The flow rate of the bypass waterway 4 can be controlled by a motor-driven water flow proportional valve 5. For example, when the flow rate of hot water is excessive and exceeds the maximum capacity of the water heater and the temperature of hot water drops below the set temperature, the flow rate of hot water can be controlled by a motor-driven proportional valve 5. The flow rate from the bypass waterway 4 is reduced by throttling the water volume proportional valve 5, and the hot water temperature is compensated to reach the set temperature.

Problems to be Solved by the Invention In the conventional configuration described above, when hot water is temporarily interrupted and hot water is again tapped, the amount of heat stored in the hot water supply heat exchanger is transferred to the water in the hot water supply heat exchanger 2 whose flow has stopped. There is a problem in that hot water is directly discharged due to the after-boiling that occurs after heating, and there is also a problem in that it is expensive to realize this.

The present invention solves the above-mentioned conventional problems, and even if hot water is temporarily interrupted and hot water is restarted, hot water due to post-boiling will not be directly tapped, the hot water temperature will be stabilized, and this can be achieved at low cost. The purpose of this invention is to provide a water heater with a bypass waterway that can be used.

Means for Solving the Problems In order to solve the above problems, the water heater with a bypass water channel of the present invention includes a bypass water channel provided in parallel with a water channel of a heat exchanger for hot water supply, and a solenoid valve provided in the bypass water channel. Then, when the water heater is used again after a temporary interruption in use, the after-boiling amount of the hot water heat exchanger is calculated from the continuous hot water supply time before the hot water supply interruption, the combustion amount immediately before the hot water supply interruption, and the hot water supply interruption time, and the If the amount of boiling water exceeds a certain amount, the solenoid valve of the bypass waterway is kept open only for a certain period of time when hot water is reused.

According to the above configuration, when the water heater is used again after a temporary interruption in use, the control means calculates the after-boiling amount from the continuous hot water supply time before the hot water supply interruption, the combustion amount immediately before the hot water supply interruption, and the hot water supply interruption time, If the after-boiling amount exceeds a certain amount, it is determined that the after-boiling of water in the hot water supply heat exchanger is significant, and the solenoid valve of the bypass waterway is kept open for a certain period of time to reduce the after-boiling in the heat exchanger. Since hot water is mixed with water in the bypass waterway and hot water is discharged, even when hot water is reused, hot water from post-boiling is not directly discharged, and a stable hot water temperature can be obtained. Furthermore, by using an inexpensive solenoid valve, costs can be reduced.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a configuration diagram of a water heater with a bypass conduit showing an embodiment of the present invention. In Figure 1, water inlet 11 is at branch point 1
2, and at a branch point 12, the water passage branches into a waterway 13 and a bypass waterway 14. One water channel 13 passes through a heat exchanger 15 for hot water supply, and the other water channel 14 passes through a solenoid valve 16 and communicates with a confluence point 17, respectively. This confluence point 1
7 communicates with an outlet 19 via a thermistor 18 for measuring the mixing temperature. Reference numeral 20 denotes a control means, which calculates the after-boiling amount of the water supply heat exchanger 15 by the control means 20 when the water heater 21 is used again after being temporarily suspended;
If the after-boiling amount is 0.5 or more, the solenoid valve 16 of the bypass waterway 14 is opened only for a certain period of time when hot water is reused.
A confluence point 1 is connected to high-temperature water generated by post-boiling in the hot water heat exchanger 15.
7, the water in the bypass waterway 14 is mixed and cooled, and the water in the outlet 1 is cooled.
The structure is such that hot water does not come out directly from 9. A fuel proportional valve 22 controls the combustion amount of the burner 23.

The operation of the above configuration will be described below.

FIG. 2 is a flowchart showing the sequence of opening and closing of the solenoid valve when the water heater with a bypass conduit according to an embodiment of the present invention is temporarily suspended and then reused. In FIG. 2, first, step 24 determines whether or not the hot water supply unit 121 has started operation, and if it is stopped, as shown in step 25, the combustion A immediately before the hot water supply stop and the combustion A immediately before the hot water supply stop are performed. The continuous hot water supply time tA up to that point is maintained, and the decision to start operation is repeated.Here, the post-boiling amount is the amount of heat held by the high-temperature fins and drums of the heat exchanger 15 immediately after combustion stops. Due to the stoppage, the fins of heat exchanger 15
Heat equivalent to the heat capacity of the drum is transferred to the stopped water in the heat exchanger water tube. Therefore, in step 26, the continuous hot water supply time tA before the most hot water supply is compared with the time TA for reaching thermal equilibrium of the heat exchanger 15 (the time taken for the heat exchanger temperature to become constant after being heated by the flame). The magnitude of the heat exchanger temperature immediately after the stop can be estimated, and if tA/TA is 1 or more, the heat exchanger temperature increase coefficient ηA is set to ηA = 1 in step 27, and if it is 1 or less, ηA = tA/TA' is set in step 28. .

Next, let us assume that the time required to transfer heat from the high-temperature fin drum of the heat exchanger 15 to the water in the water pipes of the heat exchanger 15 immediately after combustion stops is the saturated heat storage time Te of the water in the heat exchanger 15. The after-boiling amount reaches its maximum at a time Te after the water supply is stopped, and then decreases as heat is radiated from the high-temperature water in the heat exchanger 15 to the atmosphere via the fin drum. Therefore, if the hot water supply interruption time is t, which is the elapsed time from the hot water supply stop shown in step 29, then t/Te represents the state of the temporal after-boiling amount.Next, in step 30, the saturated heat storage time Te and Compare the hot water supply stop time t. Furthermore, by using the value A/I, which is the value indicating the absolute magnitude of the after-boiling amount, which is obtained by dividing the combustion A immediately before water supply is stopped by the maximum combustion amount I, the after-boiling index η can be calculated as t/I.
When T e is less than or equal to 1, as shown in step 31, tA η = end By expressing it as XTXηA, the level of the afterboiling amount can be represented by the afterboiling index η.

Next, in step 33, it is determined whether the after-boiling index η is 0.5 or more, and when the after-boiling index η is 0.5 or more, it is determined that the after-boiling of the water in the heat exchanger 15 is significant. death,
In step 34, the electromagnetic valve 16 in the bypass waterway 14 is opened for a predetermined time C to mix and cool the high-temperature water resulting from after-boiling in the heat exchanger 15 and the water in the bypass waterway 14, and tap the hot water. On the other hand, when the after-boiling index η is less than 0.5, it is determined that there is little after-boiling of the water in the heat exchanger 15, and the solenoid valve 16 of the bypass waterway 14 is closed in step 35 before hot water is tapped. It is. Furthermore, in step 36, the combustion amount is controlled in accordance with the tapped water temperature.

Note that the fixed time C during which the solenoid valve 16 is kept open is the time required for the high-temperature water generated by after-boiling in the heat exchanger 15 to complete passing through the confluence point 17 .

Therefore, even if hot water is temporarily interrupted and hot water is re-discharged, hot water resulting from post-boiling will not be directly dispensed, and a stable hot water temperature can be obtained.

Effects of the Invention As described above, according to the present invention, the solenoid valve installed in the bypass waterway calculates the amount of after-boiling, and if the amount of after-boiling exceeds a certain amount, the solenoid valve is operated for a certain period of time when hot water is reused. Since the high-temperature water from the after-boiling in the heat exchanger is mixed with the water in the bypass waterway and then tapped, the hot water from the after-boiling is not directly tapped. , it is possible to obtain a stable tapping temperature and to reduce costs by using an inexpensive solenoid valve.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a water heater with a bypass conduit showing an embodiment of the present invention, and Fig. 2 is a sequence of opening and closing of a solenoid valve when the water heater with a bypass conduit is reused after a temporary suspension of use. FIG. 3 is a block diagram of a conventional water heater with a bypass water channel. 13... Waterway, 14... Bypass waterway, 15...
Heat exchanger for hot water supply, 16... Solenoid valve, 20... Control means, 21... Water heater with bypass channel, tA... Continuous hot water supply time before stopping hot water supply, A... Immediately before stopping hot water supply Burning amount, t...Hot water supply interruption time, η...After-boiling index. Fig. 2σ / 13-=Eiji- /4--, BA 4 BA-INFU')/-KUTAI IC--・-Sakura Mei 1] Netsukashikyo' tb-4jl weaving 2f--Pa 6 bus 7

Claims (1)

[Claims] 1. A bypass waterway installed in parallel with the waterway of the heat exchanger for hot water supply, a solenoid valve installed in the bypass waterway, and a continuous hot water supply system before the hot water supply interruption when the water heater is reused after temporarily suspending its use. The after-boiling amount of the hot water heat exchanger is calculated from the time, the amount of combustion immediately before hot water supply interruption, and the hot water supply interruption time, and if the after-boiling amount is more than a certain amount, the solenoid valve of the bypass waterway is closed for a certain period of time when hot water is reused. A water heater with a bypass conduit, comprising: a control means for opening only the water heater.