JP3198767B2 - 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 the prevention of freezing in a water path of a water heater.

[0002]

2. Description of the Related Art Conventionally, a water heater of this type is disclosed in
The freezing prevention in the water path was performed by the structure as shown in Japanese Patent No. 1656.

That is, in FIG. 2, a burner 1 and a heat exchanger 2 are provided, and a plurality of heater units 4 and one thermostat 5 are attached to a pipe 3 of the heat exchanger 2, and the heater unit 4 and the thermostat 5 are connected to each other. It was electrically connected to the controller 6 in series.

In this conventional water heater, when the thermostat 5 detects a temperature near the freezing point, the contact closes to start energizing heating to the heater unit 4, and the thermostat 5
When a predetermined temperature rise is detected, the contact is opened and the heating and heating of the heater unit 4 is stopped, so that the temperature of the water in the pipe 3 of the heat exchanger 2 is kept so as not to always be below freezing, thereby preventing freezing. Things.

[0005]

However, such a conventional structure has a disadvantage that a large number of heater units 4 and thermostats 5 are required to prevent freezing, and the cost of the water heater becomes high. there were. Further, since the heating by the heater unit 4 is localized, uneven temperature occurs between the pipe 3a near the heater unit 4 and the pipe 3b away from the heater unit 4, and the pipe 3b
In order to keep the temperature of the pipe 3a below freezing, it is necessary to heat the pipe 3a to a considerably high temperature, which causes a problem that power consumption is increased and electricity cost is increased.

Accordingly, it is a first object of the present invention to provide an inexpensive water heater with a low cost, and a second object is to reduce power consumption by preventing freezing and reduce electricity bills. .

[0007]

SUMMARY OF THE INVENTION In order to achieve the first object, the present invention comprises a control device for controlling energization of a heater of a vaporizer in accordance with a temperature detected by a tapping temperature detector.

In order to achieve the second object, the present invention provides a control device for closing a damper provided in a duct connecting a burner and a blower when energizing a heater of a vaporizer for preventing freezing. It is provided with.

[0009]

According to the present invention, when the detected temperature of the tapping water temperature detector approaches the freezing point, the heating of the heater of the vaporizer is started, and the detected temperature of the tapping temperature detector rises to a predetermined temperature. At times, the heating of the heater is stopped to prevent the water in the heat exchanger from freezing, eliminating the need to attach a large number of heater units and thermostats, and reducing the cost of the water heater. Things.

Further, the air heated by energizing and heating the heater of the vaporizer is not discharged to the outside of the water heater by a natural draft from the blower to the exhaust portion by closing the damper, and the burner and the heat exchanger are connected to the burner. In this way, natural convection between the heat exchanger and the water in the heat exchanger can be uniformly heated, so that the power consumption in the prevention of freezing can be reduced and the electricity bill can be reduced.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a water heater according to one embodiment of the present invention.

In FIG. 1, reference numeral 11 denotes a burner provided with a vaporizer 13 having a heater 12, a mixing chamber 14, and a burner head 15. A fuel pump 1 is provided at a position facing the vaporizer 13.
Nozzle 17 connected to 6 is attached. 18
Is a heat exchanger in which a drum pipe 19 is wound around and a fin pipe 20 is provided at an upper part. A burner 11 is connected to a lower part, and an exhaust part 21 is attached to an upper part. A hot water supply pipe 22 and a hot water supply pipe 24 provided with a hot water temperature detector 23 are connected to the inlet side and the outlet side of the heat exchanger 18, respectively. 25 is a fan 26 and a motor 27
The burner 11 is connected to the burner 11 through a duct 28, and a damper 29 that can be opened and closed is mounted in the duct 28. Reference numeral 30 denotes a control device for controlling the combustion amount of the burner 11, controlling the energization of the heater 12, and controlling the opening and closing of the damper 29.

The operation during the hot water supply operation will be described. The liquid fuel (kerosene in this embodiment) sent from the refueling pump 16 to the nozzle 17 is dropped into the vaporizer 13 heated to a temperature equal to or higher than the vaporization temperature by the heater 12 to become vaporized kerosene.
On the other hand, the combustion air sent by the rotation of the fan 26 driven by the motor 27 of the blower 25 is adjusted in air volume by a damper 29 in a duct 28, passes through the vaporizer 13, and is mixed with the vaporized kerosene in the mixing chamber 14. Burner head 15
Where it forms a flame and generates combustion gases.
The water supplied from the water supply pipe 22 is sent from the drum pipe 19 of the heat exchanger 18 to the fin pipe 20, where the water is exchanged with the combustion gas generated by the burner 11, heated, and passed through the tapping pipe 24 as hot water. Supplied. At this time, the tapping temperature detector 23 detects the tapping temperature, and controls the combustion amount of the burner 11 by the control device so that the temperature becomes appropriate. The combustion gas after the heat exchange is discharged to the exhaust unit 21.
It is discharged to the outside of the water heater.

Next, the operation of the heater 12 of the vaporizer 13 in preventing freezing will be described. When the water heater is stopped, the temperature around the water heater drops below freezing and the heat exchanger 18
If there is a risk of freezing in the water path, such as the like, the tapping water temperature detector 23 detects a water temperature near 0 ° C., and the control device 30 starts energizing the heater 12 of the vaporizer 13, 13 is heated. When generated in the vaporizer 13, the drum pipe 19 of the heat exchanger 18 or the fin pipe 2
0, and also transmitted to a water supply pipe 22 and a hot water pipe 24 connected to the heat exchanger 18 to prevent freezing in these water paths. When the water temperature has risen sufficiently, the tap water temperature detector 23 detects a predetermined temperature, and the control device 30
By stopping the power supply to the heater 12, the series of freeze prevention operations is terminated.

In the above configuration and operation, the heating and the control for the prevention of freezing are also performed by using parts such as the heater 12 and the tapping temperature detector 23 necessary for the hot water supply operation. There is no need to attach a large number of heater units and thermostats as in the example, and the cost of the water heater can be reduced.

Next, the operation of the damper 29 in preventing freezing will be described. When energization of the heater 12 of the vaporizer 13 is started to prevent freezing, and the vaporizer 13 is heated, the movement of the heated air causes the blower 25 to move the duct 28 to the burner 11 to the heat exchanger 18 to the exhaust unit 21. There is a possibility that the heat of the vaporizer 13 may be discharged to the outside of the water heater, but the damper 29 is closed by the control device 30 and the blower 2
By blocking the ventilation between 5 and burner 11,
The air heated by the vaporizer 13 is supplied to the burner 11 and the heat exchanger 1.
8, the heat exchanger 18 is heated by the convection due to natural convection without being discharged to the outside of the water heater, and the water in the fin pipe 20 and the drum pipe 19 can be heated uniformly. Things.

In the configuration and operation described above, energization of the heater 12 for preventing freezing can be suppressed to a necessary minimum, and as a result, power consumption can be reduced and electricity cost can be reduced.

[0018]

As described above, according to the present invention, in order to prevent freezing, the energization of the heater of the vaporizer is controlled in accordance with the temperature detected by the hot water temperature detector, thereby providing a large number of heater units and thermostats. It is not necessary to attach a water heater, and the cost of the water heater can be reduced. In addition, by reducing the number of parts, the effect of improving the assembly workability and the maintenance workability can be achieved.

Further, according to the present invention, by closing the damper when energizing the heater of the vaporizer for preventing freezing, it is possible to reduce the power consumption in preventing freezing and reduce the electricity bill, and to maintain the water heater. Can be cheaper.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a water heater according to one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a conventional water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Burner 12 Heater 13 Vaporizer 18 Heat exchanger 21 Exhaust part 22 Water supply pipe 23 Hot water temperature detector 24 Hot water pipe 25 Blower 28 Duct 29 Damper 30 Control device

Continuation of the front page (56) References Japanese Utility Model Sho 61-58444 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24H 1/10 303 F23N 3/02 F23N 5/02 350

Claims (2)

(57) [Claims] A burner having a vaporizer therein;
A heat exchanger and an exhaust connected to the burner;
A blower for supplying combustion air to the heat exchanger, and water in the heat exchanger.
Energization of the heater of the vaporizer to prevent freezing of
A water heater having a control device for closing the damper when heat is applied . 2. A tapping temperature detection for detecting the temperature of the hot water in the heat exchanger.
An alarm is provided, and the control device detects the detected temperature of the tapping water temperature detector.
Turns off the power to the vaporizer heater when
When the detected temperature rises to a predetermined temperature, the heater
The water heater according to claim 1, wherein the current supply to the heater is stopped .