JP2002295846A - Heating medium leak detection prevention method for heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preventing misdetection of leakages in a heating medium in a heating apparatus for preventing misdetection, due to repetition of the repeated replenishment of the heating medium. SOLUTION: In addition to the repeated replenishment of the heating medium (hot water 6 and water W) to a heating medium tank (cistern 28), operation pause time is added as a determining element, thus preventing the misdetection of leakage in the heating medium when the pause time of the heating apparatus is long, and hence improving the reliability of operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing erroneous detection of heat medium leakage in a heating device such as a central heating system using a heat medium such as hot water.

[0002]

2. Description of the Related Art Conventionally, in a heating system using a heat medium such as hot water, for example, as shown in FIG. 6, a heating terminal 100 for floor heating is installed on the upper floor, and a cistern 102 is installed on the lower floor.
The hot water 104 is transferred from the cistern 102 downstairs to the circulation path 106.
Circulates to the heating terminal 100 on the floor.

[0003] Incidentally, a resin pipe is used for the circulation path 106, but since this resin pipe has high air permeability, outside air may enter the circulation path 106. 10
Reference numeral 8 denotes air that has entered the circulation path 106. If the operation suspension is continued, the circulation of the hot water 104 cannot be obtained, so that the air 108 may enter the circulation path 106. Further, when the heating terminal 100 is installed on the upper floor and the cistern 102 is installed on the lower floor, when the height difference between the two is large,
Since the internal pressure of the circulation path 106 decreases, the intake of the outside air becomes remarkable.

As a countermeasure against such air intrusion, by forcibly circulating the hot water 104 at intervals of about 700 hours, if the air 108 enters the circulation path 106,
A process is performed to discharge it to the cistern 102 side. That is, when the level of the hot water 104 in the cistern 102 is reduced, the water supply to the cistern 102 and the circulation are repeatedly performed.

[0005] However, in such a treatment, hot water 10
If the water supply is repeated until 4 reaches the normal level, a water leakage accident may occur if water leakage occurs in the circulation path 106. For this reason, when water replenishment is frequently performed, such control is canceled to immediately stop the operation and control to avoid a water leakage accident is performed.

In such control, a sensor 110 for detecting a low water level and a sensor 112 for detecting a high water level are installed in the cistern 102. For example, it is estimated whether or not there is a water leak based on a program process shown in FIG. are doing. That is, when the sensor 110 detects a low water level in step SA, the process proceeds to step SB and replenishes water to the cistern 102. This water replenishment is performed until the sensor 112 detects a high water level in step SC. When the water level shifts to the high water level, the water supply is stopped in step SD, and in steps SE and SF, it is determined whether or not the sensor 110 detects the low water level within a predetermined time after the water supply is stopped. Here, when the low water level is detected, the process proceeds to step SG to perform water replenishment again. This water replenishment is similarly performed until the high water level is detected in step SH, and when the high water level is detected, in step SI, Stop water supply. Then, in steps SJ and SK, it is determined whether or not the sensor 110 has detected a low water level within a predetermined time after the stop of the water supply, and when the low water level is detected in step SK, the process proceeds to step SL and an error is generated. Stop, ie
It is estimated that a water leak has occurred, and the operation is stopped.
That is, in such control, when the low water level is detected after the repetition of the water supply twice, the water leak is estimated. Such control from step SA to SK is continuously performed not only during the normal heating operation but also during the pump operation other than the heating operation.

[0007]

However, if a large amount of air 108 has entered the circulation path 106 due to suspension of operation for one month or more, water supply is repeated three or more times at the start of operation. Even so, it is expected that the hot water 104 will not reach the high water level. When the volume of the cistern 102 is designed to be smaller than the total volume of the circulation path 106 due to a demand for miniaturization or the like, and the longer the circulation path length, the smaller the supply amount from the cistern 102 and the need for repeated water supply. This is because there can be.

However, if priority is given to control for preventing a water leakage accident, water is supplied to the cistern 102. As a result, although water can be normally operated, water is supplied repeatedly. It is practically inconvenient to cancel the operation and make the operation impossible again by erroneously detecting a water leak.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for preventing erroneous detection of heat medium leakage in a heating device, which prevents erroneous detection due to repeated supply of heat medium.

[0010]

According to the present invention, there is provided a method for preventing erroneous detection of heat medium leakage in a heating apparatus, comprising the steps of:
In addition to the replenishment of the heating medium (hot water 6, water W)
By taking into account the operation suspension time as a determination factor, erroneous detection of heat medium leakage when the heating device suspension time is long is prevented, so that the operation reliability can be improved.

According to the method for preventing erroneous detection of heat medium leakage of a heating device of the present invention, a heating device for heating by circulating a heated heat medium (hot water 6) to a heating terminal (2, 4) through a circulation path (24) is provided. A method for detecting whether or not the heat medium in the heat medium tank (cistern 28) is at a predetermined lower limit level (low water level L ₁ ) based on the start of operation;
A process for determining whether or not the operation suspension is performed for a predetermined time or more; and when the heat medium in the heat medium tank is equal to or less than the lower limit level, the heat medium is stored in the heat medium tank up to a predetermined upper level (high water level L ₂ ) A process of determining whether or not the heating medium in the heating medium tank has shifted to the lower limit level within a predetermined time after stopping the supply of the heating medium, and a predetermined time after stopping the supply of the heating medium. When the heating medium in the heating medium tank has shifted to the lower limit level within a predetermined time period after the supply of the heating medium has been stopped. Until the heat medium of the heat medium tank has been shifted to the lower limit level, and a process of replenishing the heat medium tank to the upper limit level of the heat medium is repeated. I do.

That is, at the start of operation, when the heat medium in the heat medium tank has shifted to the predetermined lower limit level, it is determined whether or not the operation of the heating device has been stopped for a predetermined time or more, so that the water supply is simply repeated. Erroneous detection of heat medium leakage due to

Further, according to the method for preventing erroneous detection of heat medium leakage of a heating device of the present invention, a heated heat medium (hot water 6) is supplied to a circulation path (24).
A method for preventing erroneous detection of heat medium leakage of a heating device that circulates heat to a heating terminal (2, 4) for heating and determines whether or not operation suspension is longer than a predetermined time based on operation start; When the operation is stopped for less than a predetermined time and the heat medium in the heat medium tank is at a predetermined lower limit level (low water level L ₁ ), the heat medium is supplied to the heat medium tank to a predetermined upper limit level (high water level L ₂ ). A process of replenishing, a process of determining whether or not the heat medium of the heat medium tank has shifted to the lower limit level within a predetermined time after the supply of the heat medium is stopped, and a step of determining whether the heat medium of the heat medium tank is When shifting to the lower limit level, a process of replenishing the heating medium tank with the heating medium up to the upper limit level,
When the heating medium in the heating medium tank has shifted to the lower limit level within a predetermined time after the supply of the heating medium is stopped, a process for determining that the heating medium is leaking is included.

That is, when the operation of the heating device is stopped for less than a predetermined time at the start of operation, if the heating medium has not reached the upper limit level even though the heating medium has been replenished three times or more, a heating medium leakage may occur. Judgment and prevention of erroneous detection of heat medium leakage, avoiding heat medium leakage accidents, and improving control reliability.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention and embodiments thereof will be described below in detail with reference to embodiments shown in the drawings.

FIG. 1 shows an embodiment of a method for preventing erroneous detection of heat medium leakage in a heating apparatus according to the present invention. In the heating device according to the present invention, for example, a heating terminal 2 as a low-temperature required load composed of a floor heating panel or the like and a heating terminal 4 as a high-temperature required load composed of a fan convector or the like are installed. A gas water heater 8 is used as a heat source for supplying hot water 6 as a heat medium. As the heat medium, in addition to the hot water 6, a liquid or fluid such as antifreeze or oil can be used. As a heat source for heating the heat medium, besides the combustion heat of the fuel gas, the combustion heat of kerosene, electric heat, heat pump, solar heat and the like can be used.

The gas water heater 8 is provided with a burner 10 as a combustion means in a combustion chamber 12, and the burner 10 is provided with a fuel gas G via a valve 14, 16 or a valve 18 as a gas adjusting means or a switching means. Is supplied. Burner 1
Below 0, a fan 20 is installed as air supply means for supplying air required for gas combustion.

The gas water heater 8 includes a burner 1
A heat exchanger 22 is provided in the combustion chamber 12 as a heating means for adding 0 combustion heat to the hot water 6. This heat exchanger 22
Is provided with a circulation path 24 as means for circulating the hot water 6 to the heating terminals 2 and 4. In this embodiment, the circulation path 24 is composed of two systems, a circulation path 24A on the heating terminal 2 side and a circulation path 24B on the heating terminal 4 side. These circulation paths 24A and 24B are commonly provided with a circulation pump 26 as a heat medium pumping means and a cistern 2 as a heat medium tank for storing the heat medium.
8 are installed. AC is used as the drive source of the circulation pump 26
A motor or a DC motor can be used.
When a motor is used, the number of rotations can be controlled widely.

The high-temperature side pipe 3 is
0, a pipe 36 on the heating terminal 2 side and a pipe 38 on the heating terminal 4 side are provided along with the low-temperature side pipe 32 and the return pipe 34, and a bypass pipe is provided between the high-temperature side pipe 30 and the return pipe 34. 40 are provided. HW indicates high-temperature water and LW indicates low-temperature water. The high-temperature water HW flows to the return pipe 34 via the bypass pipe 40. For example, resin pipes are used for the pipes 36 and 38, and are connected to the high-temperature side pipe 30, the low-temperature side pipe 32, or the return pipe 34 on the gas water heater 8 side via a connection part 42. Except for the pipes 36 and 38, the pipe of the circulation path 24 is formed of a metal pipe.

A valve 44 is provided on the outgoing side of the pipe 36 on the heating terminal 2 side, and a valve 46 is provided on the pipe 38 in series with the heating terminal 4, and the valve 46 is built in the heating terminal 4 side. .

The cistern 28 has a water supply pipe 48 as a replenishing means for replenishing water W as a heat medium from the outside,
An overflow pipe 50 for discharging the overflowing hot water 6 to the outside of the cistern 28 is provided. In addition, water pipe 48
Is provided with a valve 52 as an on-off valve for controlling water supply. Further, level sensors 54 and 56 are provided as level detecting means of the hot water 6 in the cistern 28.

As shown in FIG. 2, the level sensors 54 and 56 are, as shown in FIG. 2, a low level L ₁ which is a predetermined lower limit level of the hot water 6 and a high level which is a predetermined upper limit level of the hot water 6. The water level L ₂ is electrically detected, and a detection output representing the water level is extracted as an electric signal and applied to the control unit 58.

The control unit 58 as a control means for performing heating control and the like is constituted by a microcomputer or the like, and controls heating medium leakage detection, heating medium replenishment control, heating medium circulation control, pause time measurement control, heating control, etc. Controls various controls. The detection outputs of the level sensors 54 and 56 and the like are input to the control unit 58 as control information, and various control outputs are obtained from the control unit 58. That is, the control unit 58 applies a control output to the circulation pump 26, the valves 44, 46, and 52, and the control output Vn to other actuators such as the valves 14, 16, and 18. The measurement of the pause time starts from the end of the heating operation, and ends when the heating operation starts. The measured pause time is canceled at the start of operation, and is referred to as time element data of the heat medium leak detection control.

An example of the heat medium supply control and the heat medium leak detection control in such a configuration will be described with reference to a flowchart shown in FIG.

When the operation switch is turned on to start the heating operation, the pump is always operated before the heating operation to control the water circulation in the circulation path 24. The control shown in the flowchart of FIG. During the normal heating operation, that is, during the pump operation and during the stop, the operation is continuously executed.

In this control, the level sensor is set in step S1.
L is low water level L₁Processing to determine whether or not
Perform, low water level L₁If no is detected, step S2
Move to In step S2, when this heating operation is constant
At least for a while, a determination process is performed to determine whether or not it has been suspended. This one
The suspension of the heating operation for a fixed time or more
After the operation of sending hot water 6 has been completed, the next heating operation
Is the time until the start. Pause for more than a certain time
If not, the process returns to step S1.
If not, the process proceeds to step S3, and the level sensor
54 is low water level L ₁It is determined whether or not is detected.

The hot water 6 of the cistern 28 has a low water level L₁In
In step S4, the valve 52 is opened to
A replenishment process is performed, and the level sensor 56 goes high in step S5.
Water level L_TwoProcess to determine whether or not
Hot water 6 is at high water level L in top S5 _TwoWhen you reach
The process proceeds to step S6, in which the valve 52 is closed to stop water supply.
You. That is, the low water level L₁Water supply starts when water is detected
And high water level L_TwoWhen reaching, stop water supply.

[0028] After this water replenishment, in step S7, after the stop, a fixed time within process of determining whether or not carried out, whether or not determination processing level sensor 54 at step S8 is detecting the low water level L ₁ I do. Step S7, S8 after determining whether or not shifts from the high level L ₂ to the low level L ₁ within a predetermined time when a transition to the low level L _1, step S
9, water supply is started, and in step S10, the level sensor 5
After detecting whether or not the hot water 6 is at the high water level L ₂ , the hot water 6
When the number reaches ₂ , the process proceeds to step S11, and the water supply is stopped. If you do not enter a low water level L ₁ is within a predetermined time, returns from the step S7 to the step S1.

[0029] Then, at the start of operation, when the hot water 6 in the cistern 28 in step S1 is low level L _1, the process proceeds to step S12, performs a water replenishment process by opening the valve 52, the hot water 6 high in step S13 when detecting whether the host vehicle has reached the water level L _2, it has reached the high water level L _2, step S
The process proceeds to 14, and the valve 52 is closed to stop water supply.
That is, when the hot water 6 is in the low level L _1, performs water replenishment until it reaches the high water level L _2.

The absence After this water replenishment, the process proceeds to step S15, performs a process of determining whether or not within a predetermined time after the water supply stops, the process proceeds to step S16, whether the level sensor 54 detects the low water level L ₁ Is determined. That is, the high water level L whether the transition from ₂ to the low level L ₁ to determine within a predetermined time, if no transition within a predetermined time in the low water level L _1, the process returns to step S1.

Low water level L within a certain time₁Has moved to
Then, the process proceeds to step S17, in which the valve 52 is opened to
The feeding process is performed, and the level sensor 56
Water level L _TwoIs performed to determine whether or not a high water level L has been detected.
_TwoIs reached, the process proceeds to step S19, and the valve 5
Close 2 to stop water replenishment. That is, the warm water 6 has a low water level L.
₁At high water level L_TwoWater until it reaches
U.

After this water replenishment, step S20
The processing proceeds to step S21 to determine whether or not it is within a predetermined time after the stop of water supply.
There it is determined whether or not the processing has been detected low water L _1. That is, the high water level L whether the transition from ₂ to the low level L ₁ to determine within a predetermined time, if no transition within a predetermined time in the low water level L _1, the process returns to step S1.

[0033] When a transition to the low level L ₁ within a predetermined time, the process proceeds to step S22, performs an error stop is determined that there is a leak. That is, the operation is canceled when the water supply is stopped.

As described above, not only is the replenishment of the water supply to the cistern 28 repeated, but also the determination of the time element as to whether or not the suspension of the heating device is longer than a predetermined time results in the suspension of the heating device. Can eliminate the shortage of the heat medium due to the intrusion of air into the circulation path 24, prevent erroneous detection of water leakage and malfunctions such as operation stop based on the erroneous detection, and improve the reliability of the control operation.

Next, FIG. 4 shows another embodiment of the level sensor installed on the cistern 28. As shown in FIG. In this embodiment, a pressure sensor 60 is installed on the bottom side of the cistern 28 as a level sensor, and detects and extracts each level such as a low water level L ₁ and a high water level L ₂ from the pressure acting on the pressure sensor 60. The same heat medium supply control can be performed using such a detection output.

Next, FIG. 5 shows another embodiment of the level sensor installed on the cistern 28. In FIG. In this embodiment, an ultrasonic sensor 62 is provided as a level sensor on the upper surface side of the cistern 28.
2 measures the time required for the reflected wave Sr of the ultrasonic Si emitted toward the surface of the hot water 6 to reach the ultrasonic sensor 62, thereby obtaining the low water level L ₁ , which is the normal control level of the hot water 6, each level of such high water L ₂ can be taken out, it is possible to perform the same heat medium supply control even with such a detection output.

In this embodiment, the water supply is performed within the range of steps S4 to S11 in the flowchart of FIG.
The water supply is repeated twice in the range from step S12 to step S21, but three or more times of water supply may be repeated together with the water level determination.

Further, in the embodiment, the water W is supplied to the cistern 28 as a heat medium supply. However, the water W or the hot water 6 as the heat medium may be supplied to the circulation path 24 other than the cistern 28. Good.

[0039]

As described above, according to the present invention,
The following effects are obtained. a When the heating system is stopped for a long period of one month or more and a large amount of air enters the circulation path, normal operation is possible by repeatedly supplying the heating medium to the heating medium tank. In spite of the above, as a result of repeated supply of the heat medium, erroneous detection of heat medium leakage can be avoided, and the reliability of operation can be improved. b Since it is determined whether air has entered the circulation path or the heat medium has leaked based on the pause time of the heating device, the supply of the heat medium, and the level of the heat medium, it is necessary to install special equipment such as air detection means and heat medium leak sensors. Therefore, it is possible to shift to the heating operation or to shift to the heating operation after removing the air based on the determination result, thereby realizing highly reliable control. c If such a method for preventing erroneous detection of heat medium leakage is adopted,
A resin tube with high air permeability can be used for the circulation path,
The characteristics of a resin tube that is lightweight and has good workability can be utilized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a method for preventing erroneous detection of heat medium leakage in a heating device according to the present invention.

FIG. 2 is a diagram showing a cistern provided with a level sensor.

FIG. 3 is a flowchart showing control for preventing erroneous detection of heat medium leakage.

FIG. 4 is a diagram showing another embodiment of a level sensor in a systern.

FIG. 5 is a diagram showing another embodiment of a level sensor in a systern.

FIG. 6 is a view showing air intrusion in a pipe.

FIG. 7 is a flowchart showing conventional heat medium leakage control.

[Explanation of symbols]

2, 4 heating terminal 6 hot water (heat medium) 24 circulation path 28 cistern (heat medium tank) L ₁ low water (lower level) L ₂ high water (upper level)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3L070 AA00 BB03 BC02 BC30 DE08 DF15

Claims (2)

[Claims] 1. A method for preventing erroneous detection of heat medium leakage in a heating device for heating by circulating a heated heat medium through a circulation path to a heating terminal, wherein the heat medium in a heat medium tank is set to a predetermined temperature based on the start of operation. A process of determining whether or not the heat transfer medium is at a lower limit level; a process of determining whether or not the operation stoppage is performed for a predetermined time or more; A process of replenishing the heat medium to the upper limit level of the heat medium; a process of determining whether the heat medium in the heat medium tank has shifted to the lower limit level within a predetermined time after the supply of the heat medium is stopped; When the heating medium in the heating medium tank has shifted to the lower limit level within a predetermined time after the supply of the medium has stopped, a process of replenishing the heating medium tank with the heating medium up to the upper limit level. A predetermined time has passed since the replenishment of Until the heating medium in the heating medium tank has shifted to the lower limit level, and a process of replenishing the heating medium tank with the heating medium up to the upper limit level is repeated. Method for preventing erroneous detection of heat medium leakage in a heating device. 2. A method for preventing erroneous detection of heat medium leakage in a heating device for heating by circulating a heated heat medium to a heating terminal through a circulation path, comprising: When the operation suspension is less than a predetermined time, when the heat medium in the heat medium tank is at a predetermined lower limit level, a process of replenishing the heat medium tank with the heat medium to a predetermined upper limit level, A process of determining whether or not the heating medium in the heating medium tank has shifted to the lower limit level within a predetermined time after the supply of the heating medium has stopped, and the heating medium in the heating medium tank has shifted to the lower limit level. When the heating medium is supplied to the heating medium tank up to the upper limit level, and when the heating medium in the heating medium tank shifts to the lower limit level within a predetermined time after the supply of the heating medium is stopped, the heating medium Processing to determine a leak, A method for preventing erroneous detection of heat medium leakage in a heating device, comprising: