METHOD FOR OPERATING A WATER CIRCULATION SYSTEM

Abstract

A method for operating a water circulation system having at least one valve and at least one temperature sensor; determining a first temperature and a second temperature; determining a period of time; detecting the water temperature using at least one temperature sensor; detecting the opening time during which the at least one valve is at least partially open at least partially opening the at least one valve if the detected water temperature exceeds the value of the first temperature or if the opening time reaches the period of time; and completely closing the at least one valve if the detected water temperature reaches the value of the second temperature.

Claims

1. A method for operating a water circulation system comprising the steps of: providing the water circulation system, comprising: at least one supply line (1), at least one return line (2), at least one strand (3) which connects the supply line (1) with the return line (2), at least one temperature control unit (4), which connects the supply line (1) with the return line (2), whereby water can circulate in a flow direction from the at least one supply line (1), via the at least one strand (3), the at least one return line (2) and the temperature control unit (4) back to the supply line (1), at least one consumer (5), which is arranged along the at least one line (3) and with which water can be drawn from the circulation system, at least one valve (6) with which the flow rate of the water in the circulation system can be changed, at least one temperature sensor (60,61,62) with which the water temperature can be detected in a line section, at least one control unit with which the data from the temperature sensors (60, 61, 62) can be processed and with which the at least one valve (6) can be actuated; defining a first temperature (T.sub.1); defining a second temperature (T.sub.2); defining a time duration (Z.sub.D); detecting the water temperature with the at least one temperature sensor (60,61,62); detecting the opening time during which the at least one valve (6) is at least partially open; opening the at least one valve (6) at least partially when the detected water temperature reaches the value of the first temperature (T.sub.1) or when the opening time reaches the time duration (Z.sub.D); completely closing the at least one valve (6) when the detected water temperature reaches the value of the second temperature (T.sub.2).

2. The method according to claim 1, comprising the step of: recording the course of the recorded temperature.

3. The method according to claim 2, comprising the steps of: determining the gradient of the recorded temperature profile; changing the opening of the valve (6) based on the determined temperature gradient.

4. The method according to claim 2, comprising the steps of: assigning the recorded temperature profile to a specific consumption (V.sub.1,2,3); changing the opening of the valve (6) based on the specific consumption.

5. The method according to claim 2, comprising the steps of: defining at least one trigger threshold; detecting a time interval (I.sub.1,2,3) during which the at least one trigger threshold is exceeded; assigning a specific consumption (V.sub.1,2,3) to the recorded time interval (I.sub.1,2,3).

6. The method according to claim 1, comprising the steps of: defining at least one time window (Z.sub.F); executing the method within the at least one time window (Z.sub.F); opening the at least one valve (6) at least partially outside of the at least one time window (Z.sub.F).

7. The method according to claim 1, comprising the steps of: extending the time duration (Z.sub.D) if the water temperature detected at the beginning of the at least partial valve opening is above the value of the first temperature (T.sub.1); shortening the time duration (ZD) if the water temperature detected at the beginning of the at least partial valve opening is below the value of the first temperature (T.sub.1).

8. The method according to claim 1, wherein the at least one temperature sensor (61) is arranged in the immediate vicinity of the at least one valve (6) or wherein the at least one temperature sensor (61) is arranged in the at least one valve (6).

9. The method according to claim 1, wherein the water circulation system comprises a temperature sensor (60) on the supply line (1) in the area of the temperature control unit (4), with which the supply temperature (T.sub.V) can be detected and/or wherein the water circulation system comprises a temperature sensor (62) in the area of the temperature control unit (4) with which the return temperature (T.sub.R) can be detected.

10. The method according to claim 1, wherein the water circulation system comprises two or more strands (3) each with at least one consumer (5), at least one valve (6) and at least one temperature sensor (60,61,62), wherein each of the strands (3) comprises its own control unit or wherein all strands (3) comprise a common control unit.

11. The method according to claim 1, wherein the water circulation system comprises a pump (7), a non-return valve (8) and a filter (9).

12. The method according to claim 1, wherein the at least one temperature control unit (4) comprises a heating unit or a cooling unit.

13. The method according to claim 11, wherein the water circulation system comprises at least one hot water circulation system with a heating unit and a cold water circulation system with a cooling unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Embodiments of the current invention are described in more detail in the following with reference to the figures.

[0063] These are for illustrative purposes only and are not to be construed as limiting. It shows

[0064] FIG. 1 a schematic representation of a water circulation system for carrying out the method according to the invention;

[0065] FIG. 2 a schematic representation of a temperature profile in a strand of the water circulation system of FIG. 1;

[0066] FIG. 3 a schematic illustration of a further temperature profile in a strand of the water circulation system of FIG. 1; and

[0067] FIG. 4 a schematic illustration of a temperature profile in a strand of the system of FIG. 1 during specific consumptions.

DETAILED DESCRIPTION OF THE INVENTION

[0068] FIG. 1 shows a schematic representation of a water circulation system for carrying out the method according to the invention. The system comprises a supply line 1, a return line 2, two strand 3 which connect the supply line 1 to the return line 2. The system further comprises a temperature control unit 4, which connects the supply line 1 with the return line 2, whereby in one flow direction, water can circulate from the supply line 1, via the two strands 3, the return line 2 and the temperature control unit 4 back to the supply line 1. The system further comprises several consumers 5, which are arranged along the strand 3 and with which water can be drawn from the circulation system. In each strand 3, a valve 6 is provided, which is arranged in the region of the strand 3 which opens into the return line 2. I.e. the valve 6 is arranged in the region of the end of the strand 3. With each valve 6, the flow rate of the water in the respective strand can be changed. In the supply line 1, in the area of the temperature control unit 4, a temperature sensor 60 is provided with which the supply temperature T.sub.V can be detected. A further temperature sensor 61 is provided in the strand 3 in the area of the valve 6, with which the strand temperature T.sub.S can be detected. In the return line 2, in the area of the temperature control unit 4, a further temperature sensor 62 is provided, with which the return temperature T.sub.R can be detected. The system further comprises a strand-specific or an overall control unit (not shown) with which the data from the temperature sensors can be processed and with which the at least one valve can be actuated. A circulation pump 7 is provided in the return line 2, with which water can be conveyed from the strands 3 via the return line 2 to the temperature control unit 4. A check valve 8 is provided between the pump 7 and the temperature control unit 4, which prevents water from flowing back from the temperature control unit 4 to the pump 7. A public supply line leads from the public water connection to the temperature control unit 4. A filter 9 is provided in the public supply line, which can clean the tap water from the public connection. A check valve 8 is provided between the filter 9 and the public connection, which prevents water from flowing back from the temperature control unit 4 to the public connection.

[0069] FIG. 2 shows a schematic diagram of a temperature profile in a strand 3 of the water circulation system of FIG. 1.

[0070] In a hot water system, the tap water circulates in the first intervals I.sub.1 and the water stands still in the second intervals I.sub.2. The strand temperature T.sub.S is kept between the first temperature T.sub.1 and the second temperature T.sub.2. If the temperature sensor of the strand indicates that the measured water has the first temperature T.sub.1, the valve 6 is opened at least partially, as a result of which the water temperature in the strand 3 rises. When the strand temperature T.sub.S reaches the second temperature T.sub.2, the valve 6 is closed. When the valve 6 is closed, the strand temperature T.sub.S decreases over time. If it reaches the first temperature T.sub.1, the valve is opened again. The more the valve is opened, the faster the second temperature is reached and the shorter the heating interval.

[0071] In a cold water system, the tap water circulates in the second intervals I.sub.2 and the water stands still in the first intervals I.sub.1. As soon as the circulation starts, the strand temperature T.sub.S decreases and as soon as the water stands still in the strands, the temperature of the strand water increases.

[0072] FIG. 3 shows a schematic representation of a further temperature profile in a strand 3 of the water circulation system of FIG. 1. In the temperature profile shown, the valve 6 is at least partially open in the first section, as a result of which the temperature T.sub.S measured in the strand increases. If the predefined second temperature T.sub.2 is reached, the valve 6 is completely closed. The valve is kept closed for a first period of time Z.sub.D1, as a result of which the measured strand temperature T.sub.S decreases over time. After the first time period Z.sub.D1 has elapsed, the valve is opened again and the water temperature of the strand is determined. If the determined temperature is higher than the predefined first temperature T.sub.1, then the second time period Z.sub.D2 following the first time period Z.sub.D1 is extended. This is repeated until the period is such that when the valve is opened, the strand temperature corresponds to the first temperature. If, after opening the valve, a water temperature is determined which is lower than the first temperature, the next time period is shortened.

[0073] FIG. 4 shows a schematic representation of a temperature profile in a strand of the system of FIG. 1 during specific consumption levels V.sub.1,V.sub.2,V.sub.3. If the strand temperature T.sub.S changes only slightly during a short interval I.sub.1, then this can be assigned to hand washing V.sub.1. A larger change in temperature over a longer interval I.sub.2 can be assigned to a shower V.sub.2 and a large change in the strand temperature over a long interval I.sub.3 can be assigned to filling up a bathtub V.sub.3. In a further alternative, the time is taken into account at which the measured temperature in a hot water system falls below a predetermined temperature or exceeds it in a cold water system. Such a trigger or release threshold can be set in such a way that, for example, minor temperature fluctuations are ignored and the time of the temperature drop is only taken into account when the trigger threshold is exceeded. The trigger threshold can be 0.1° C., 0.2° C., 0.4° C., 0.5° C., 1° C., 1.5° C., 2° C., 2.5° C., 3° C. or more. The trigger threshold can also be used to identify specific consumptions. The time during which the trigger threshold is exceeded is measured. Very short times, i.e. times of less than 5 seconds can be ignored. With a time of 5 to 15 seconds, it can be concluded that someone was washing their hands at a sink, for example. With a time of 30 seconds to 15 minutes, for example, a shower can be recognized and with a time of 10 to 30 minutes the taking of a bath can be recognized. The recording of the temperature profile can be designed in such a way that it only takes place when the measured temperature in the strand exceeds the trigger threshold, i.e. the deviation from the set temperature exceeds a certain value. Alternatively, as described above, the time during which the trigger threshold is exceeded can be measured to determine a specific consumption V.sub.1,V.sub.2,V.sub.3. The time interval during which the trigger threshold is exceeded can therefore be used to identify the specific consumption. A very short interval can be ignored. A short interval indicates hand washing, a longer interval indicates showering and a long interval indicates taking a bath.

[0074] Several trigger thresholds can also be defined so that the determination is not based solely on time, i.e. based on the length of the intervals. In this way, it can be determined during which time which trigger threshold is exceeded. If only the first trigger threshold is exceeded, this indicates hand washing. If the first trigger threshold is exceeded during a first interval and a second trigger threshold is exceeded during a second interval, the first trigger threshold being smaller than the second and the first interval being longer than the second, this indicates showering. Any number of trigger thresholds and intervals can be combined with one another and compared for an evaluation. The preset strand temperature can also be used as the trigger threshold.

TABLE-US-00001 REFERENCE SIGNS LIST 1 Supply line I.sub.1,2,3 Interval 2 Return line T.sub.V Supply temperature 3 Strand T.sub.S Strand temperature 4 Temperature control T.sub.R Return temperature unit T.sub.1 First temperature 5 Consumer T.sub.2 Second temperature 6 Valve V.sub.1,2,3 Consumption 60 Temperature sensor Z.sub.D Time duration 61 Temperature sensor Z.sub.F Time window 62 Temperature sensor 7 Pump 8 Non-return valve 9 Filter