JPS587213Y2 - Freeze prevention circuit for hot water boiler - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an antifreeze circuit for a hot water boiler, and its purpose is to provide an antifreeze circuit for a hot water boiler that is capable of economical antifreeze operation.

In the conventional freeze prevention circuit of this type of hot water boiler,
To prevent hot water boiler piping from freezing, turn on the main switch, set the hot water temperature setting to the lowest setting with the temperature setting volume, and activate the combustion control circuit when the hot water temperature reaches the set temperature. Freeze prevention was used, so even if the outside temperature did not fall below the freezing point, if the hot water temperature in the hot water boiler reached the lowest temperature, the combustion control circuit would operate regardless of the outside temperature, which was very uneconomical. .

The present invention was devised to eliminate the above-mentioned drawbacks, and will be explained below with reference to the drawings.

Figure 1 shows a heating system using the anti-freeze circuit for hot water boilers according to the present invention.
are connected by an outgoing pipe 3 and a return pipe 4, and a circulation pump 5 is attached to the outgoing pipe 3, and a sensor section 6 of an antifreeze thermostat is attached to the return pipe 4.

In addition, 7 is a remote control unit that controls the hot water boiler 1 from indoors;
8 is a thermistor that detects the temperature of hot water inside the hot water boiler 1.

FIG. 2 shows an embodiment of the antifreeze circuit for a hot water boiler according to the present invention, in which 9 is a power transformer, 10 is a rectifier circuit, and 11 is a main switch installed in the remote control unit 7 in FIG. , 12 is a temperature setting volume which is also installed in the remote control unit 7 and works in conjunction with the main switch 11 to set the hot water temperature to a temperature on the low temperature side (for example, near the freezing point) when the main switch 11 is turned off. 13 is a hot water setting temperature. and the hot water temperature inside the hot water boiler 1, and when the hot water temperature inside the hot water boiler 1 is lower than the hot water set temperature, a thermo circuit that excites the excitation winding 14, 15 is energized by opening and closing of the contact 16 of the excitation winding 14. combustion control circuit, which is controlled by
17 and 18 are excitation windings operated by sequence control of the combustion control circuit 15, 19 are excitation windings that are energized and excited when the contact 16 is closed, 20 is a switch section of an antifreeze thermostat, and 21 and 22 are excitation windings. Contacts 23 and 24 of the winding 17 are contacts of the excitation winding 18, 25 is a contact of the excitation winding 19, 26 is a burner motor, and 27 is an ignition transformer 28, which is a solenoid valve.

The antifreeze circuit for a hot water boiler of the present invention having the above configuration operates as follows.

Turn on the main switch 11, set the hot water temperature with the temperature setting volume 12 linked with the main switch 11, and if the set hot water temperature is low, the thermo circuit 13 will turn on the excitation winding. The contact 16 is closed by the excitation of the excitation winding 14, and the combustion control circuit 1 is energized.
5 is energized.

The combustion control circuit 15 is energized to perform sequence control, the excitation winding 17 is energized, the contacts 21 and 22 are closed, and the burner motor 26 and ignition transformer 27 start operating.

Incidentally, the circulation pump 5 is activated when the main switch 11 or the antifreeze switch 20 is closed.

When a certain period of time elapses after the excitation winding 17 is energized by the sequence control of the combustion control circuit 15, the excitation winding 18 is energized, and the excitation winding 17 is de-energized instead.

When the excitation winding 17 is de-energized, the contact 21.2
2 is opened, and the excitation of the excitation winding 18 causes the contact 23.2 to open.
4 is closed.

By closing the contacts 23, 24, the burner motor 26 continues to operate, and the solenoid valve 28 is opened to supply fuel and start combustion.

When the hot water temperature in the hot water boiler 1 becomes higher than the set hot water temperature due to the combustion operation of the combustion control circuit 15, the thermo circuit 13 de-energizes the excitation winding 14, and the contact 16 closes when the excitation winding 14 is de-energized.
is opened, power to the combustion control circuit 15 is cut off, and combustion is stopped.

When the hot water boiler 1 is not used, the main switch 11 is turned off.

(At this time, the hot water temperature in the hot water boiler 1 is set by the temperature setting volume 12 linked to the main switch 11 to a temperature on the low temperature side.

) When the outside temperature is close to the freezing point, the sensor part 6 of the anti-freeze thermometer attached to the return pipe 4 detects the temperature, and the switch part 20 of the anti-freeze thermometer installed in parallel with the main switch 11 is closed, and the hot water is turned off. When the hot water temperature in the boiler 1 reaches the temperature set by the temperature setting volume 12, the thermo circuit 13 operates as described above, and the combustion control circuit 15 subsequently performs sequence control to perform the combustion operation, and the hot water boiler 1 The internal ice temperature is raised to prevent freezing.

As described above, in the antifreeze circuit for a hot water boiler according to the present invention, the temperature setting knob for setting the hot water temperature and the main switch are linked, and when the main switch is turned off, the hot water temperature is set to the low temperature side by the temperature setting volume. The sensor part of the anti-freeze thermometer is attached to the piping such as the return pipe that circulates hot water to the heat exchanger and other usage parts, and the switch part is installed in parallel with the main switch, so the main switch can be used when the hot water boiler is not in use. If the outside temperature is close to the freezing point and the water in the hot water boiler and piping is about to freeze, the anti-freeze thermo sensor will detect a temperature close to the freezing point due to the drop in outside temperature and the switch will close. Therefore, the combustion operation of the hot water boiler is performed.

Therefore, in the anti-freezing circuit for a hot water boiler according to the present invention, if the hot water temperature inside the hot water boiler reaches the lowest setting temperature set by the temperature setting volume before the outside temperature drops to near the freezing point as in the conventional hot water boiler, regardless of the outside temperature. Eliminates the disadvantage of hot water boiler operation,
Economical operation is carried out.

In addition, by simply turning off the main switch when the hot water boiler is not in use, the necessary temperature settings for freezing prevention can be made, and the hot water boiler can be automatically operated in the event of danger of freezing.
Not only is it easy to use, it also prevents freezing without waste.
And it will be done reliably.

Furthermore, since the sensor section of the antifreeze thermometer is attached to the piping that circulates and supplies hot water from the hot water boiler to the usage section, it has the advantage that it is easy to sensitively detect a drop in water temperature due to a drop in outside temperature.

[Brief explanation of the drawing]

FIG. 1 shows a heating system using the antifreeze circuit for a hot water boiler according to the present invention, and FIG. 2 shows an embodiment of the antifreeze circuit for a hot water boiler according to the present invention. 1...Hot water boiler, 6...Sensor section,
8... Thermistor, 11... Main switch, 12... Temperature setting volume, 20...
...Switch section.

Claims (1)

[Scope of utility model registration request] In a hot water boiler equipped with piping that circulates and supplies hot water to the usage part, the temperature set by the temperature setting volume is compared with the hot water temperature inside the hot water boiler, and the combustion control circuit is activated when the hot water temperature is lower than the set temperature. A thermo circuit, a main switch connected in series with the thermo circuit and interlocked with a temperature setting volume so that the hot water temperature setting becomes a temperature on the low temperature side when turned off, a sensor section attached to the piping, and the main switch. An anti-freeze circuit for a hot water boiler, comprising a switch part connected in parallel to the freezing point, and an anti-freeze thermostat whose sensor part detects a temperature close to the freezing point and closes the switch part.