CN111023578A - Water heater outlet water temperature control method and control system - Google Patents
Water heater outlet water temperature control method and control system Download PDFInfo
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- CN111023578A CN111023578A CN201911238392.4A CN201911238392A CN111023578A CN 111023578 A CN111023578 A CN 111023578A CN 201911238392 A CN201911238392 A CN 201911238392A CN 111023578 A CN111023578 A CN 111023578A
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 196
- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000010438 heat treatment Methods 0.000 claims description 21
- 239000000523 sample Substances 0.000 claims description 6
- 238000002485 combustion reaction Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2035—Arrangement or mounting of control or safety devices for water heaters using fluid fuel
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)
Abstract
The invention discloses a control method and a control system for the outlet water temperature of a water heater, wherein the control method comprises the steps of setting a preheating temperature T and a minimum thermal load Qmin(ii) a Detecting the temperature T of the inlet water1Water flow L and water outlet temperature T in pipeline2(ii) a Calculating real-time required heat load Q; judging whether the real-time required heat load Q is larger than the minimum heat load Qmin(ii) a Judging whether the water heater works in the minimum heat load state or not and continuously judging the outlet water temperature T2Is greater than the preheating temperature T. According to the technical scheme, the real-time required heat load is compared with the minimum heat load, and whether the water heater is started to heat or not is judged; when the water heater works in the state of minimum heat load, the temperature T of the outlet water is adjusted2And comparing the temperature with the preheating temperature T, judging whether the water heater stops working or not, and ensuring that the water outlet temperature of the water heater cannot be too high.
Description
Technical Field
The invention relates to the technical field of water heaters, in particular to a water heater outlet water temperature control method and a water heater outlet water temperature control system.
Background
The existing gas water heater judges whether to carry out combustion work or not through the following process, firstly, a flow sensor is utilized to detect the water flow in a pipeline, when the water flow in the pipeline is larger than a set value L1, the gas water heater is started to carry out combustion work, and when the water flow in the pipeline is smaller than a set value L2, the gas water heater is closed to stop the combustion work.
From the above description, it can be seen that the existing gas water heater only uses the water flow in the pipeline as the judgment whether to start combustion. However, in practical applications, if the inlet water temperature of the gas water heater is high and the gas water heater starts to burn, even if the gas water heater works under the minimum heat load, the outlet water temperature may be higher than the set temperature, which may cause a user to be scalded due to the non-constant temperature or even the over-high temperature.
Disclosure of Invention
The present invention is directed to a method and a system for controlling the outlet water temperature of a water heater, so as to solve one or more technical problems in the prior art and provide at least one useful choice or creation condition.
The technical scheme adopted for solving the technical problems is as follows:
a water heater outlet water temperature control method comprises the following steps:
step 100, respectively setting a preheating temperature T and a minimum heat load Qmin;
Step 200, respectively detecting the water inlet temperature T1And the water flow rate L in the pipeline;
step 300, according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
step 400, judging whether the real-time required heat load Q is larger than the minimum heat load QminIf so, controlling the water heater to start heating, otherwise forbidding the water heater to start;
step 500, detecting the temperature T of water2;
Step 600, during the starting period of the water heater, judging whether the water heater works in the minimum heat load state, if so, continuously judging the outlet water temperature T2And if so, controlling the water heater to stop heating.
As a further improvement of the above technical solution, the calculation formula of the real-time required thermal load Q in step 300 is as follows, where Q is (T + Δ T)1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in step 100.
As a further improvement of the above technical solution, the first margin temperature Δ T1Is 2 degrees celsius.
As a further improvement of the above technical solution, in step 600, the outlet water temperature T is judged2Whether or not it is greater than the preheating temperature T and the second margin temperature DeltaT2And, if so, controlling the water heater to stop heating, and controlling the second residual temperature delta T2Set in step 100.
As a further improvement of the above technical solution, the second margin temperature Δ T2At 4 degrees celsius.
This application still discloses a water heater leaving water temperature control system simultaneously, includes:
an initialization module for setting a pre-heating temperature T and a minimum thermal load Qmin;
A water inlet temperature probe for detecting the water inlet temperature T1;
Water outlet temperature probe for detecting water temperature T2;
The flow sensor is used for detecting the water flow L in the pipeline;
a heat load calculation module for calculating the heat load according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
a first comparison module for comparing the real-time required heat load Q with the minimum heat load QminComparing;
a second comparison module for comparing the outlet water temperature T during the start-up period of the water heater and when the water heater is in the minimum heat load state2Comparing with the preheating temperature T;
a control module for controlling the start and stop of the water heater, if the real-time required heat load Q is largeAt said minimum thermal load QminControlling the water heater to start heating, otherwise forbidding the water heater to start; if the outlet water temperature T is in the minimum heat load state during the starting period of the water heater2And controlling the water heater to stop heating when the temperature is higher than the preheating temperature T.
As a further improvement of the above technical solution, a calculation formula of the real-time required heat load Q in the heat load calculation module is as follows, where Q ═ T + Δ T1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in the initialization module.
As a further improvement of the above technical solution, the first margin temperature Δ T1Is 2 degrees celsius.
As a further improvement of the above technical solution, in the second comparing module, the preheating temperature T and the second margin temperature Δ T are compared2And the water outlet temperature T2Making a comparison, the second margin temperature Delta T2Set in the initialization module.
As a further improvement of the above technical solution, the second margin temperature Δ T2At 4 degrees celsius.
The invention has the beneficial effects that: the technical scheme includes that the real-time required heat load of the water heater is calculated by detecting the water inlet temperature and the water flow in a pipeline and combining the set preheating temperature, and whether the water heater is started for heating is judged by comparing the real-time required heat load with the minimum heat load; during the starting of the water heater, when the water heater works in the minimum heat load state, the temperature T of the outlet water is adjusted2Comparing the temperature with the preheating temperature T, and judging whether the water heater stops working or not; this technical scheme is through optimizing the start-up and the stop condition to the water heater, guarantees that the water temperature of water heater can not appear too high the condition.
Drawings
The invention is further described with reference to the accompanying drawings and examples;
FIG. 1 is a flow chart of a control method of the present invention.
Detailed Description
Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, if words such as "a plurality" are described, the meaning is one or more, the meaning of a plurality is two or more, more than, less than, more than, etc. are understood as excluding the present number, and more than, less than, etc. are understood as including the present number.
In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.
Referring to fig. 1, the application discloses a water heater outlet water temperature control method, which comprises the following steps:
step 100, respectively setting a preheating temperature T and a minimum heat load Qmin;
Step 200, respectively detecting the water inlet temperature T1And the water flow rate L in the pipeline;
step 300, according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
step 400, judging whether the real-time required heat load Q is larger than the minimum heat load QminSuch asIf so, controlling the water heater to start heating, otherwise forbidding the water heater to start;
step 500, detecting the temperature T of water2;
Step 600, during the starting period of the water heater, judging whether the water heater works in the minimum heat load state, if so, continuously judging the outlet water temperature T2And if so, controlling the water heater to stop heating.
In this embodiment, step 400 is set to the starting condition of the water heater, and when the real-time required heat load Q is greater than the minimum heat load QminAt this time, it is proved that enough heat is needed to heat the water entering the water heater so as to prevent the outlet water temperature of the water heater from being too low; set in step 400 is a stop condition for the water heater, which proves that it is not necessary to heat the water entering the water heater with excessive heat when the water heater is operating in a minimum thermal load condition, in this case if the outlet temperature T is such that2And if the temperature is higher than the preheating temperature T, the outlet water temperature of the water heater meets the requirement, and if the water heater is continuously heated, the outlet water temperature is too high, so that the water heater needs to be stopped in time.
In the embodiment, the real-time required heat load of the water heater is calculated by detecting the water inlet temperature and the water flow in the pipeline and combining the set preheating temperature, and whether the water heater is started for heating is judged by comparing the real-time required heat load with the minimum heat load; during the starting of the water heater, when the water heater works in the minimum heat load state, the temperature T of the outlet water is adjusted2Comparing the temperature with the preheating temperature T, and judging whether the water heater stops working or not; this technical scheme is through optimizing the start-up and the stop condition to the water heater, guarantees that the water temperature of water heater can not appear too high the condition.
In a further preferred embodiment, in the present embodiment, the calculation formula of the real-time required thermal load Q in step 300 is as follows, where Q ═ T + Δ T1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in step 100. Specifically, the first residual temperature Δ in the present embodimentT1Is 2 degrees celsius. This embodiment leads to the setting of first surplus temperature guarantees the accuracy of water heater heating back leaving water temperature.
Further preferably, in this embodiment, in step 600, the outlet water temperature T is determined2Whether or not it is greater than the preheating temperature T and the second margin temperature DeltaT2And, if so, controlling the water heater to stop heating, and controlling the second residual temperature delta T2Set in step 100. Specifically, the second residual temperature Δ T in the present embodiment2At 4 degrees celsius. This embodiment is through the setting of second surplus temperature guarantees that water heater leaving water temperature can guarantee in longer time that leaving water temperature can maintain near preheating temperature.
The application also discloses a water heater leaving water temperature control system simultaneously, its first embodiment includes:
an initialization module for setting a pre-heating temperature T and a minimum thermal load Qmin;
A water inlet temperature probe for detecting the water inlet temperature T1;
Water outlet temperature probe for detecting water temperature T2;
The flow sensor is used for detecting the water flow L in the pipeline;
a heat load calculation module for calculating the heat load according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
a first comparison module for comparing the real-time required heat load Q with the minimum heat load QminComparing;
a second comparison module for comparing the outlet water temperature T during the start-up period of the water heater and when the water heater is in the minimum heat load state2Comparing with the preheating temperature T;
a control module for controlling the start and stop of the water heater, if the real-time required heat load Q is larger than the minimum heat load QminControlling the water heater to start heating, otherwise forbidding the water heater to start; during the starting of water heaterWhen the water outlet temperature T is in the minimum heat load state2And controlling the water heater to stop heating when the temperature is higher than the preheating temperature T.
In a further preferred embodiment, in the present embodiment, a calculation formula of the real-time required thermal load Q in the thermal load calculation module is as follows, where Q ═ T + Δ T1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in the initialization module. Specifically, the first residual temperature Δ T in the present embodiment1Is 2 degrees celsius.
In a further preferred embodiment, in the second comparing module, the preheating temperature T and the second margin temperature Δ T are compared2And the water outlet temperature T2Making a comparison, the second margin temperature Delta T2Set in the initialization module. Specifically, in this embodiment, the second residual temperature Δ T2At 4 degrees celsius.
While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that the present invention is not limited to the details of the embodiments shown and described, but is capable of numerous equivalents and substitutions without departing from the spirit of the invention as set forth in the claims appended hereto.
Claims (10)
1. A water heater outlet water temperature control method is characterized by comprising the following steps: the method comprises the following steps:
step 100, respectively setting a preheating temperature T and a minimum heat load Qmin;
Step 200, respectively detecting the water inlet temperature T1And the water flow rate L in the pipeline;
step 300, according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
step 400, judging whether the real-time required heat load Q is larger than the minimum heat load QminIf yes, controlling the water heater to start heating, otherwise, controlling the water heater to start heatingForbidding the water heater to start;
step 500, detecting the temperature T of water2;
Step 600, during the starting period of the water heater, judging whether the water heater works in the minimum heat load state, if so, continuously judging the outlet water temperature T2And if so, controlling the water heater to stop heating.
2. The method for controlling the outlet water temperature of the water heater according to claim 1, wherein: the calculation formula of the real-time required heat load Q in step 300 is as follows, where Q ═ T + Δ T1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in step 100.
3. The method for controlling the outlet water temperature of the water heater according to claim 2, characterized in that: the first margin temperature DeltaT1Is 2 degrees celsius.
4. The method for controlling the outlet water temperature of the water heater according to any one of claims 1 to 3, wherein: in step 600, the outlet water temperature T is judged2Whether or not it is greater than the preheating temperature T and the second margin temperature DeltaT2And, if so, controlling the water heater to stop heating, and controlling the second residual temperature delta T2Set in step 100.
5. The method for controlling the outlet water temperature of the water heater according to claim 4, wherein: the second residual temperature DeltaT2At 4 degrees celsius.
6. The utility model provides a water heater leaving water temperature control system which characterized in that: the method comprises the following steps:
an initialization module for setting a pre-heating temperature T and a minimum thermal load Qmin;
A water inlet temperature probe for detecting the water inlet temperature T1;
Water outlet temperature probe for detecting water temperature T2;
The flow sensor is used for detecting the water flow L in the pipeline;
a heat load calculation module for calculating the heat load according to the preheating temperature T and the water inlet temperature T1And the water flow L, calculating the real-time required heat load Q;
a first comparison module for comparing the real-time required heat load Q with the minimum heat load QminComparing;
a second comparison module for comparing the outlet water temperature T during the start-up period of the water heater and when the water heater is in the minimum heat load state2Comparing with the preheating temperature T;
a control module for controlling the start and stop of the water heater, if the real-time required heat load Q is larger than the minimum heat load QminControlling the water heater to start heating, otherwise forbidding the water heater to start; if the outlet water temperature T is in the minimum heat load state during the starting period of the water heater2And controlling the water heater to stop heating when the temperature is higher than the preheating temperature T.
7. The water heater leaving water temperature control system according to claim 6, characterized in that: the calculation formula of the real-time required heat load Q in the heat load calculation module is as follows, where Q ═ T + Δ T1-T1) L, wherein Δ T1Represents a first residual temperature Δ T1Set in the initialization module.
8. The water heater leaving water temperature control system according to claim 7, characterized in that: the first margin temperature DeltaT1Is 2 degrees celsius.
9. The water heater leaving water temperature control system according to any one of claims 6 to 8, characterized in that: in the second comparison module, the preheating temperature T and a second margin temperature Delta T are compared2And the temperature of the outlet waterDegree T2Making a comparison, the second margin temperature Delta T2Set in the initialization module.
10. The water heater leaving water temperature control system according to claim 9, characterized in that: the second residual temperature DeltaT2At 4 degrees celsius.
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
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CN111721003A (en) * | 2020-06-01 | 2020-09-29 | 华帝股份有限公司 | Water heater water temperature control method and water heater water temperature control system |
CN111780426A (en) * | 2020-07-02 | 2020-10-16 | 广东万家乐燃气具有限公司 | Water flow control system and control method of gas water heater |
CN113266951A (en) * | 2021-04-30 | 2021-08-17 | 广东万家乐燃气具有限公司 | Control method and control system of gas water heater and gas water heater |
CN114111051A (en) * | 2020-08-31 | 2022-03-01 | 芜湖美的厨卫电器制造有限公司 | Heating control method, hot water assembly and computer readable storage medium |
CN114183931A (en) * | 2021-12-16 | 2022-03-15 | 珠海格力电器股份有限公司 | Control method and control device of heater |
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CN104236109A (en) * | 2013-06-24 | 2014-12-24 | 海尔集团公司 | Control method and control device of constant-temperature gas water heater |
CN110440449A (en) * | 2019-07-16 | 2019-11-12 | 华帝股份有限公司 | Control method of water heater system |
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CN111721003A (en) * | 2020-06-01 | 2020-09-29 | 华帝股份有限公司 | Water heater water temperature control method and water heater water temperature control system |
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CN113266951A (en) * | 2021-04-30 | 2021-08-17 | 广东万家乐燃气具有限公司 | Control method and control system of gas water heater and gas water heater |
CN114183931A (en) * | 2021-12-16 | 2022-03-15 | 珠海格力电器股份有限公司 | Control method and control device of heater |
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