JPH0799280B2 - Freezing prevention device for hot water heater with forced reheating - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antifreezing device for a water heater, which is capable of supplying hot water, heating a bath, and the like.

2. Description of the Related Art Conventionally, the structure of this type of hot water heater with forced heating has been as shown in FIG. That is, the hot water supply branch circuit 4 is branched from the hot water supply side of the hot water supply heat exchanger 2, and the first solenoid valve 6, the rim cutting hopper 7 and the second solenoid valve 8 are used to the suction side of the pump 11 of the bath circuit 22, The hot water supply branch circuit 4 and the bath branch circuit 9 are indirectly connected. And by the action of the pump 11, it seems to bathe
When hot water is supplied to 20, open the first solenoid valve 6 and the second solenoid valve 8
With the solenoid valve 13 closed, hot water is supplied through the bath outflow pipe 15 to fill the water. To prevent the bath circuit 22 from freezing, the freezing prevention switch 16
When ON, the second solenoid valve 8 is closed, the third solenoid valve 13 is opened, and the bath water is bathed by the action of the pump 11, the bath heat exchanger 10, the bath outflow pipe 15, the bathtub 20, the bath return pipe 19, and the third It is circulated in a bath circuit 22 composed of a solenoid valve 13 and a running water switch to prevent freezing. In the figure, 18 is a control unit.

Problems to be Solved by the Invention With such a structure, in order to prevent the freezing of the bath circuit 22, it is necessary to always put a certain level of water or more in the bath 20 so that after bathing, I can't throw away hot water. Also, to prevent freezing, it is necessary to add more water to the remaining hot water when there is no water above a certain level after bathing. Therefore bath
If you forget to fill the water above 20 with a certain level, the pump function will stop working and the bath circuit 22 will freeze, and the preparation for bathing the next day will require the work of discarding the hot water of the previous day. Moreover, there was a problem that the wall surface of the bath was dirty with the remaining hot water.

Like the general bathing habit, the present invention automatically prevents the freezing of the bath circuit 22 without throwing water after bathing and filling the bath, and immediately after the next bathing, such as the next day, immediately after the bath The purpose is to be able to work and to reduce the stain on the bath.

Means for Solving the Problems The technical means of the present invention for solving the above problems is a hot water supply branch circuit which is branched from a hot water supply circuit and has a first solenoid valve, and which is cut off to the hot water supply branch circuit. A bath branch circuit which is connected and has a second solenoid valve, a circulation pump whose suction side is connected to this bath branch circuit, and a third solenoid valve which is located upstream of the connection portion of this pump with the bath branch circuit. Third
A bath circuit including a bath outward pipe and a bath return pipe connected to a solenoid valve, a pump, and a bath heat exchanger is connected to the upstream side of the third solenoid valve of the bath outward pipe and the bath return pipe, and Bypass path with solenoid valve, antifreeze switch to prevent freezing of the bath circuit, and when this antifreeze switch is ON,
Open the 1st, 2nd and 4th solenoid valves, close the 3rd solenoid valve, operate the pump, and when the 1st solenoid valve is open, burn the hot water supply, and freeze prevention switch is OFF. At this time, the first, second, and fourth solenoid valves are closed, and the third solenoid valve is opened to configure a control unit for operating the pump and operating the hot water supply circuit.

Action The action of this technical means is as follows. In other words, when the outside air temperature falls below the temperature level set to prevent freezing of the bath circuit, the antifreezing switch turns on, the antifreezing operation of the control unit works, and the fourth solenoid valve in the bypass is opened. Become. Further, the third solenoid valve on the upstream side of the pump is closed, the second solenoid valve of the bath branch circuit is opened, and the first solenoid valve of the hot water supply branch circuit is also opened. At this time, the combustion of the hot water supply side starts and the pump is also driven, so that the water in the hot water supply circuit flows into the bath through the hot water supply branch circuit, the bath branch circuit, and the bath outflow pipe and the bath return pipe. Next, by performing combustion on the hot water supply side, the temperature inside the water heater itself rises,
When the bath circuit freeze protection level is exceeded, the freeze protection switch is turned off and the control unit closes the first solenoid valve to stop hot water combustion. The second solenoid valve and the fourth solenoid valve are closed, and the third solenoid valve is open. This operation state is repeated intermittently to automatically prevent the bath circuit from freezing.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, the hot water supply circuit 5 is composed of a hot water supply pipe 5a, a hot water supply heat exchanger 2 and a hot water supply pipe 5b, and has a hot water supply / flow switch 3 for detecting the flow of water in the middle of the hot water supply pipe 5a. Further, a hot water supply branch circuit 4 is provided downstream of the hot water supply heat exchanger 2, and the hot water supply branch circuit 4 is opened and closed by the first solenoid valve 6 to control water. The hot water supply branch circuit 4 indirectly connects the hopper 7 and the second solenoid valve 8 and is communicated with the bath branch circuit 9. The bath branch circuit 9 is connected to the upstream side of the pump 11 of the bath circuit 22, that is, the suction side. . The bath circuit 22 is connected to the pump 11 via the bath heat exchanger 10, the bath upstream pipe 15, the bath bath 20, and the bath return pipe 19 and the third solenoid valve 13 provided on the upstream side of the connection with the bath branch circuit 9. It is connected to the bath heat exchanger 10 on the downstream side of the pump 11 and circulates water by the action of the pump.
Further, a bypass passage 17 connected to the upstream side of the third solenoid valve 13 from the bath upstream pipe 15 is provided, and a fourth passage is provided in the bypass passage 17.
It has a solenoid valve 14. Further, the freeze prevention switch 16 for controlling the on / off of the freeze prevention operation of the bath circuit 22, the freeze prevention switch 16, the solenoid valves 6, 8, 13, 14 and the pump 11 are connected to each other, and the control unit 18 for controlling the whole is connected. The water heater body 1
It is placed inside.

By the control unit 18, the first solenoid valve 6 is always operated during hot water supply operation.
By closing the tap and opening the faucet, the hot water supply / running water switch 3 detects the flow of water and is turned on, and the hot water supply / burning operation is performed.
Detects the flow of water and turns on, and the bath combustion operation is performed. At this time, the first solenoid valve 6, the second solenoid valve 8, the fourth solenoid valve
Control is performed so that 14 is closed and the third solenoid valve 13 is open. During anti-freezing operation, that is, when the outside temperature drops and the anti-freezing switch 16
When is ON, the control unit 18 opens the first solenoid valve 6,
Start hot water supply combustion. Also, the second solenoid valve 8 and the fourth solenoid valve 14
Is opened, the third solenoid valve 13 is closed, and the pump 11 is driven so that the hot water of the hot water supply branch circuit 4 is pumped by the bath branch circuit 9, the bath heat exchanger 10, the bath outflow pipe 15, and the bypass line 17, It is transported to the bath 20 via the bath return pipe 19. At this time, it does not matter whether the drain plug 21 of the bath 20 is open or closed. When the freezing prevention switch 16 detects an increase in the outside air temperature due to the hot water supply combustion operation due to the inflow of water in the hot water supply branch circuit 4 and the temperature increase due to the passage of hot water in the bath circuit 22, the antifreezing switch 16 will be
When turned off, the control unit 18 closes the first solenoid valve 6, the second solenoid valve 8, the fourth solenoid valve 14, opens the third solenoid valve 13, and stops the pump 11. In this state, when the antifreezing switch 16 is turned on again due to the decrease in the outside air temperature, the antifreezing operation is repeated as described above. Thus, the freezing of the bath circuit 22 is automatically prevented.

EFFECTS OF THE INVENTION As described above, according to the present invention, the anti-freezing switch of the bath circuit can be provided without constantly filling the bath with water above a certain level.
When turned on, the first, second, and fourth solenoid valves are opened, the third solenoid valve is closed, the pump is operated, and the hot water heated by the hot water heat exchanger passes from the hot water supply circuit through the bath branch circuit to the bath heat exchange. From the hot water supply device to the bath outflow pipe, and then to the bypass passage and is sent to the bathtub through the bath outflow pipe and the bath return pipe, and the cold water of the bath circuit remaining in the heat exchanger or pump is supplied from the hot water supply heat exchanger. Freezing can be prevented by replacing with warm water.

[Brief description of drawings]

FIG. 1 is a block diagram of a hot water heater with forced heating according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional example. 4 ... Hot water supply branch circuit, 5 ... Hot water supply circuit, 6 ... First solenoid valve, 8 ... Second solenoid valve, 9 ... Bath branch circuit, 11 ... Pump, 13 ... Third solenoid valve, 14 …… 4th solenoid valve, 16 …… Anti-freezing switch, 17 …… Bypass path, 18 …… Control unit.

Claims (1)

[Claims] 1. A hot water supply branch circuit branched from a hot water supply circuit and having a first solenoid valve, a bath branch circuit having a second solenoid valve connected to the hot water supply branch circuit by cutting it off, and this bath branch circuit. A circulation pump with the suction side connected to the third, which is located upstream of the connection part of this pump with the bath branch circuit
A solenoid valve, a bath circuit consisting of a bath outward pipe and a bath return pipe connected to this third solenoid valve, a pump and a bath heat exchanger, and between the bath upstream pipe and the upstream side of the third solenoid valve of the bath return pipe. A bypass path which is connected and has a fourth solenoid valve, an antifreezing switch for preventing freezing of the bath circuit, and when the antifreezing switch is ON, opens the first, second and fourth electromagnetic valves, 3 When the solenoid valve is closed, the pump is operating, and the second solenoid valve is open, start combustion by hot water supply operation, and when the antifreezing switch is OFF, the first, second, and fourth solenoid valves Is closed, the third solenoid valve is opened, and a control unit for operating the pump and operating the hot water supply circuit is provided.