JPH01208657A - Trouble monitoring device for electric hot-water heater - Google Patents

Abstract

PURPOSE:To enable a rapid displaying of an occurrence of an accident of line of a heater and a leakage of a hot water supplying pipe by a method wherein an energization time of the heater is measured and a value of a difference of a mean temperature across the energization time is compared with a set value. CONSTITUTION:A heater 12 is stored within a hot-water storage tank 11 for an electric water heater 10, a signal 15a outputted from a temperature sensor 15 is inputted to a mean temperature determining means 16 and then its mean temperature TA is inputted to a boiling control means 17 together with a target temperature Ts. A starting time to and a finishing time t1 of a checking time tc are defined within an energization time range of a midnight electrical power, an energization time tH of the heater 12 within the checking time tck is measured, a difference T between mean temperatures TAo and TA within the hot-water storage tank 11 across the energization time tH is compared with a set value (k). In response to whether the temperature difference T is larger than the set value (k), it is judged whether the heater 12 is normal or not and this is displayed at a displaying means 26.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention is a failure monitor for electric water heaters for detecting boiling failures due to breakage of the boiling heater or leaks in the hot water supply piping system. Regarding equipment.

BACKGROUND OF THE INVENTION Electric water heaters that use late-night electricity to boil water and use the hot water during the day are widely used.

This device uses an electric heater to boil water in the hot water storage tank, and when this hot water is used, water is automatically replenished into the hot water storage tank, and the hot water storage tank is always used with full water. It looks like this.

In addition, since the amount of hot water that can be used during daytime hours mainly depends on the boiling temperature, data on past hot water usage, etc., should be used to ensure that there is no shortage of hot water. In order to minimize power consumption, a technology for optimally determining the boiling temperature has been developed and is known as a microcomputer type electric water heater.

Problem to be Solved by the Invention According to the prior art, for example, if a part of the heater becomes defective, hot water will not be boiled properly, but the fact is that the amount of usable hot water will be reduced. The problem was that it was extremely difficult to use as a whole because it was only revealed as a lack of information and no other indication was made.

In other words, if we consider a case where a part of the heater is disconnected while the heater is energized during the late-night power supply period, the boiling temperature will be lower than the predetermined value because the power consumption in the heater is insufficient. It gets lower. However, the effect becomes clear to the user only when all the hot water is used and water comes out from the hot water faucet, so there is a long delay before the failure is discovered.

In addition, in electric water heaters, when there is a leak of hot water from the hot water supply pipe system, a similar phenomenon is detected as a lack of hot water, but in this case too, there is no way to detect the failure early. Ta.

Therefore, in view of the actual state of the prior art, an object of the present invention is to directly check the operating performance of the heater, thereby displaying an accurate and early warning of the occurrence of a heater disconnection accident, a leak in the hot water supply pipe system, etc. An object of the present invention is to provide a new failure monitoring device for an electric water heater that can perform the following functions.

Means for Solving the Problems The configuration of the present invention for achieving the object includes a timer means, a comparison means, and a display means, the timer means measuring the energization time of the heater within the check period,
The gist is that the comparison means compares the average temperature difference of the hot water storage tank before and after the energization time with a set value, and that the display means is activated by the output of the comparison means.

The check period can be set to the time when hot water is least used among the late-night electricity supply hours, and the comparison operation in the comparison means is performed when the heater electricity supply time is longer than a predetermined value. It may also be possible to perform this only when the conditions are met.

In this configuration, the comparing means calculates the average temperature difference of the hot water storage tank before and after the energization time of the heater, and compares this with a set value to check the operational performance of the heater. In other words, if a part of the heater is disconnected, the average temperature difference in the hot water tank will be small because the heater consumes less power, so it is possible to detect and display this. .

On the other hand, when there is a leak in the hot water pipe system, the same amount of water as the amount of water leaked is replenished into the hot water storage tank, so the average temperature difference in the hot water storage tank becomes smaller than the predetermined value, and it is detected as a failure. It is possible to do so.

Note that if hot water is used during the check period, the average temperature difference will appear smaller, making it difficult to distinguish it from a malfunction. If so, the risk of malfunction can be reduced. Furthermore, if a minimum value greater than or equal to a predetermined value is set as the energization time of the heater, it is possible to ensure that the average temperature difference during normal conditions is greater than a certain level, thereby further increasing the reliability of failure detection.

It works as described above.

Example Examples will be described below with reference to the drawings.

The electric water heater failure monitoring device 20 is a boiling control device C.
It forms part of the TR and includes a timer means 24, a check period setting means 25, a comparison means 22, and a memory means 23 (FIG. 1).

The electric water heater 10 includes a heater 12 installed inside a hot water storage tank 11 having a water supply pipe 11a and a hot water supply pipe 11b. The heater 12 is connected to a power source AC via a switching element 14 and a timer 13 that determines the time period during which late-night power is supplied. Moreover, a plurality of temperature sensors 15, 15, . . . are attached to the hot water storage tank 11 in the vertical direction.

Temperature signals 1, 5 which are outputs of temperature sensors 15, 15...
a is collectively guided to the boiling control device CTR and input to the average temperature determining means 16.

The output of the average temperature determining means 16 is input as the average temperature TA in the hot water storage tank 11 together with the boiling target temperature Ts to the boiling control means 17, and the output of the boiling control means 17 is input as the opening/closing control signal 17a. switching element 14
It is connected to the.

The output of the average temperature determining means 16 is branched into a comparing means 22 and a memory means 23. The output of the memory means 23 is input to the comparison means 22 as the average temperature TAo in the hot water storage tank 11 at the time when the boiling start signal 24a is output from the timer means 24. Also, comparison means 2
2, the setting value k is also input.

The output of the boiling control means 17 is branched into the timer means 24, and the output is input into the comparison means 22 and the memory means 23 as the energization time tH of the heater 12 and the boiling start signal 24a, respectively. ing. Further, the timer means 24 receives the start time to and end time t1 of the check period tck from the check period setting means 25, while the output signal 22a from the comparison means 22 is connected to the display means 26. ing.

Now, the timer 13 determines the period during which late-night power is applied to the heater 12, and the boiling control means 17 determines the current average temperature TA in the hot water storage tank 11, which is the output of the average temperature determining means 16, and the boiling target. By comparing the temperature Ts and outputting an opening/closing control signal 17a to the switching element 14, it is possible to boil the water in the hot water storage tank 11 to a predetermined boiling target temperature Ts using late-night electricity. can.

On the other hand, the check period setting means 25 selects an appropriate time within the 1iT7 electric time period for late-night electricity, and sets the check period t.
The starting time to and the ending time t1 of ck are determined (Fig. 2).

Here, the check period tck refers to a time period for checking whether the boiling performance of the heater 12 is equal to or higher than a predetermined value. As reflected in the increase in the average temperature TA in the hot water storage tank 11, the hot water in the hot water tank 11 is used as little as possible, for example, after the midpoint of the late-night electricity supply period, for a period of approximately one hour. It is better to define

The timer means 24 measures the energization time tH of the heater 12 within the check period tck and outputs it. That is, when the boiling control means 17 starts energizing the heater 12, the timer means 24 starts measuring the energization time tH and simultaneously outputs a boiling start signal 24a to the memory means 23.

On the other hand, the comparing means 22 can compare the difference Δ1' between the average temperatures TAo and TA in the hot water storage tank 11 before and after the energization time tH of the heater 12 with a set value. As mentioned above, the average temperature 'r'Ao is determined by the boiling start signal 24a.
The hot water storage tank 1 stored in the memory means 23 corresponding to
Since it is the average temperature within 1, the average temperature difference △T = TA - T
Ao indicates the average temperature rise due to energization of the heater 12 over the energization time tl+. That is, it can be determined whether the heater 12 is normal or not depending on whether the average temperature difference ΔT is larger than the set value, and the result is:
It can be displayed on the display means 26. In addition, hot water pipe 1
When there is a leak from the 1b system, the same amount of water as the amount of water leakage is replenished, so similarly, the average temperature difference ΔT appears small and can be detected by the comparing means 22.

Such a failure monitor device 20 can also be realized by software using a microcomputer (FIG. 3).

It is assumed that this program starts operating upon detecting the arrival of the start time to of the check period tck by a clock program (not shown). However, since the start time to can be defined, for example, by the passage of a predetermined period of time after the start of the late-night power supply period, this program can be started by a simple timer program instead of a clock program. .

The program first waits for the heater 12 to be energized (step (1) in the figure, hereinafter simply referred to as (1)), and measures the energization time tll of the heater 12 within the check period tck. (2). Next, the average temperature TA in the hot water storage tank 11 at that time is memorized as the average temperature TAo3)
, executes a timed element of a predetermined length (4).

Next, it is confirmed that the energization time tl of the heater 12 is a predetermined value (5), and the average temperature TA at that time is determined.
is read (6), and the average temperature difference ΔT=TA−TAo is calculated (7). Compare the average temperature difference △T with the set value (8), and if the former is smaller than the latter, the heater 12
A warning can be output to the effect that a defect in the hot water supply pipe 11b or a leak in the hot water supply pipe 11b system is expected (9).

Here, the time element of step (4) is the check period t
It can be thought of as giving the final tl of ck, and the step (
5) The predetermined value tIIL is set to the minimum length, considering that the average temperature difference ΔT may not be clearly expressed unless the actual energization time LH of the heater 12 is greater than or equal to the room. This stipulates the following. The set value can be determined based on the average temperature difference Δ'F that is expected when the heater 12 is in a normal state and is energized at a predetermined value t HL or more.

Now, if we compare FIG. 1 and FIG.
), below, the memory means 23 performs step (3), the timer means 24 performs steps (1) and (2), and the check period setting means 25 performs a clock program (not shown) and step (4). They correspond to each other.

According to the detailed description of the invention, the invention includes a timer means;
Comprising a comparison means and a display means, the timer means measures the energization time of the heater, the comparison means compares the magnitude of the average temperature difference before and after that with a set value, and the display means displays the result. By doing so, a defective heater or a leak in the hot water pipe system can both be flagged as a lack of average temperature difference.
The detection timing at this time is much earlier than the timing at which the user recognizes that the amount of boiling water is insufficient.
Appropriate measures can be taken quickly, and the risk of a failure being left unaddressed, resulting in repeated shortages of hot water or a large amount of energy being wasted can be effectively eliminated. This has an excellent effect.

[Brief explanation of the drawing]

1 to 3 show an embodiment, in which FIG. 1 is an overall block diagram, FIG. 2 is an operation explanatory diagram, and FIG. 3 is a program flowchart. tH...Heater energization time tHL...Predetermined value△
T...Average temperature difference k...Set value tck...Check period [0...Start period tl...End period 10...Electric water heater 11...Hot water tank 12...Heater 20.・・・
Failure monitoring device 22... Comparison means 24... Timer means 25...
- Check period setting means 26...display means

Claims (1)

[Scope of Claims] 1) A timer means for measuring the energization time of the heater within the check period, a comparison means for comparing the average temperature difference of the hot water storage tank before and after the energization time with a set value, and an output of the comparison means A failure monitoring device for an electric water heater, comprising: a display means operated by the 2) The failure monitoring device for an electric water heater according to claim 1, wherein the check period is set during a time period during which hot water is least used among late-night power supply time periods. 3) The failure monitoring device for an electric water heater according to claim 1 or 2, wherein the comparison means performs the comparison operation only when the energization time is equal to or greater than a predetermined value.