EP4336102A1 - Method for evaluating an installation of a gas-air connection of a heating device, gas-air connection and computer program - Google Patents

Abstract

Method for evaluating an installation of a gas-air combination (1) of a heater (2), which has an air line (3) with a blower (4) and a gas line (5) with a gas fitting (6), the method being at least comprises the following steps: a) providing flow reference values (SR) of a gas flow through the gas fitting (6) when modulating the air flow by means of the blower (4); b) monitoring current flow values (S) of a gas flow through the gas fitting (6) at a Modulation of the air flow by means of the fan (4);c) Determining a deviation (A) of the current flow values (S) of the gas flow from the flow reference values (SR) of the gas flow;d) Evaluating the deviation (A);e) Inferring a cause the deviation (A).

Description

The invention relates to methods for evaluating an installation of a gas-air combination of a heater, a gas-air combination of a heater and a computer program. The invention relates in particular to electronic gas-air systems and their installation, whereby these realize a gas volume flow adjustment using an electronically controlled gas fitting.

Condensing heaters usually have a modulating gas burner. This can be designed with a pneumatic gas-air combination. Here, a differential pressure is generated using a blower for air at a throttle point (orifice), which can act (directly) on a membrane in the gas solenoid valve. When the fan speed is changed as needed, the pressure on the membrane changes, so that more or less gas is added to the mixture accordingly. The gas-air ratio is therefore set with a fixed characteristic curve that is only designed for one type of gas.

The modulating gas burner can be designed with an electronic gas-air combination. The volume flows of air and gas (electronically controlled) can be supplied independently of one another or mixed with one another. Heaters with a method for combustion control are known, which exploit the dependence of the ionization current on the excess air. Depending on the power required by the heater, a speed signal for the air blower and also a specification for an electronic stepper motor of the gas valve can be generated and transmitted become. The correctness of the process or installation can then be checked, for example based on the exhaust gas and/or flame quality. The advantage of flame monitoring is that the required sensor, namely the ionization electrode, is already present in many gas heaters.

In the course of the introduction or conversion of electronic gas-air systems and/or gas quality-adaptive heat cells, not only the scope of functions increases, but also the complexity of the respective boiler systems. On the one hand, this increases the possibility of incorrect installation/incorrect adjustment, and on the other hand, these complex systems usually react much more sensitively to incorrect settings or components.

Due to a desired high degree of reuse of components of the heating devices and/or the possibility of displaying many previously mechanically represented variances via setting options, undesirable incorrect settings can occur when setting up or converting the heating devices. These can lead to a wide variety of error patterns that are difficult to analyze afterwards. Examples include installing a gas fitting that was not intended for this device and/or setting the wrong gas type/gas family (classification for gases that are similar in their physical and combustion properties, e.g. natural gas, liquid gas, hydrogen, biogas).

It is therefore the object of the invention to at least partially alleviate the problems described with reference to the prior art. In particular, a method for evaluating a subsequent installation of an (electronic) gas-air combination in an existing heating device (or heat cell) should be specified, so that an incorrectly set gas family and/or the use of a gas fitting that is not configured for this heating system is safe is recognizable. Furthermore, a suitable gas-air combination and, if necessary, a computer program suitable for its regulation should be proposed.

A method according to claim 1 contributes to solving this problem. Advantageous refinements and further developments of the invention are specified in the dependent claims. The description, particularly in conjunction with the drawings, illustrates the invention and gives further exemplary embodiments.

A method is proposed for evaluating an installation of a gas-air combination of a heater, which has at least one air line with a fan and at least one gas line with a gas fitting. The method relates in particular to the evaluation of a new or re-installation of a heater that is already known or has already been in operation. This can mean, for example, that a conversion to an electronic gas-air combination and/or to the combustion of a different type of gas/gas family has been carried out. The evaluation of the installation of the gas-air system includes, in particular, an examination of the equipment (device and/or system-specific) design and/or equipment setting of components of the gas-air system, and particularly preferably of the adjustment components of the flows of gas and/or air. As part of the assessment of the installation of the gas-air combination, a real flow behavior of the gas-air combination can be compared with an expected flow behavior, and thus the suitability of the (overall apparatus system of the) gas-air combination, particularly with regard to an expected one or real gas, which is pumped with the gas-air network, can be analyzed.

The structure of an (electronic) gas-air network has already been explained in the introduction, so these explanations can be used here. The at least one air line and the at least one gas line usually open into a mixture channel, which then supplies the fuel gas mixture to a burner. The air and the fuel gas mixture can be conveyed by setting up the operation of the (at least one) fan or the like. The supply of gas can be regulated, for example, by means of a electronically controllable stepper motor of the gas fitting, whereby the (combustion) gas leaving the gas fitting can then be sucked into the air flow.

The burner can be provided in a separate burner housing and, for example, comprise a (cylindrical) perforated plate, so that the fuel gas mixture can pass through the holes in the perforated plate and be ignited and burned on its surface. It is possible to monitor the formation of the flames on the surface of the burner, for example with flame monitoring, which was also explained in the introduction. This can be used to measure the quality of the combustion, which mainly depends on the ratio of air to gas during combustion (lambda value, also called the air ratio), and, for example, to carry out an ionization measurement in a flame area.

1. a) Bereitstellen von Strömungsreferenzwerten einer Gasströmung durch die Gasarmatur bei einer Modulation der Luftströmung mittels des Gebläses;
2. b) Überwachen aktueller Strömungswerte einer Gasströmung durch die Gasarmatur bei einer Modulation der Luftströmung mittels des Gebläses;
3. c) Feststellen einer Abweichung der aktuellen Strömungswerte der Gasströmung von den Strömungsreferenzwerten der Gasströmung;
4. d) Bewerten der Abweichung;
5. e) Schließen auf eine Ursache der Abweichung.

The method proposed here includes at least the following steps:

1. a) providing flow reference values for a gas flow through the gas fitting when the air flow is modulated by means of the fan;
2. b) monitoring current flow values of a gas flow through the gas fitting while modulating the air flow by means of the blower;
3. c) determining a deviation of the current flow values of the gas flow from the flow reference values of the gas flow;
4. d) assessing the deviation;
5. e) Infer a cause of the deviation.

The specified sequence of steps a), b), c), d) and e) can usually occur at least once during a regular operational procedure. It is possible for the steps to be carried out with different frequency, at different time intervals from one another and/or at least partially overlapped in time. The process can be triggered at any time, for example by an installer. If applicable The gas-air system or the heater can (also) independently recognize or specify at what point in time the process is initiated.

According to step a), flow reference values of a gas flow through the gas fitting can be provided when the air flow is modulated by means of the blower. These can be values that consist of historical current values or were derived or learned from them. The flow reference values can be device or system specific (embossed), i.e. e.g. B. also take into account or map the specific installation situation, the state of wear, influences of other components, etc. The flow reference values can form an (optimal or permissible) characteristic curve of the gas flow over the modulation range of the air flow that can be set by the fan. The (optimal or permissible) characteristic curve may have been determined or learned based on the (previous) operation of the heater using, for example, flame monitoring. The “flow reference value” of the gas flow is understood to be a specific (target) value or a (target) value range that is assigned to a specific (actual) value of the air flow. The flow reference values can be stored in a data memory and accessed or read out as needed or permanently.

In a (test) operation, current (actual) flow values of the gas flow through the gas fitting can be monitored when the air flow is modulated or changed using the fan. It is possible that a specific (test) modulation range is specified, which is used here. However, it is also or equally possible that the normal power requirement of the heater that is currently being requested is present and this situation is observed. The flow values of the gas flow recorded can also be assigned to a course dependent on time or air flow. The flow values can be recorded using sensors, whereby an actuator that generates/influences the flow and/or an actuator that generates/influences the flow can be monitored directly.

In particular, when a (predeterminable) sufficient monitoring time has been reached, the current behavior of the flow values can be evaluated with the flow reference values once, timed and/or (temporarily) in parallel. A (given significant) deviation of the current flow values of the gas flow from the (historically usual) flow reference values of the gas flow can be determined.

If this situation has occurred, an assessment of the identified deviation can be carried out (immediately). The evaluation can in particular include a comparison of a difference that occurs over time or during air modulation between the current flow values of the gas flow and their flow reference values, possibly also with a weighting of different modulation ranges, inclusion of further process or system parameters, etc. If both curves For example, if they form characteristic curves or ranges, their relative position to one another can be taken into account (computationally).

The result of the assessment leads to a conclusion regarding the cause of the deviation. To do this, the result can, for example, be compared with a table that contains sample results for a plurality or even a large number of causes. The cause can thus be identified and reported as a process product. In other words, when a deviation is detected, not (only) the flow parameter is adjusted, as is the case with normal control of the burner, so that the flame has a desired property and/or a predetermined lambda value is achieved, but rather information about the cause is provided Provided that is available, broadcast and/or displayed. For example, cause information about the components (which adjust the flow) of the gas-air combination and/or the gas can be stored in a table (database), from which at least one is selected using the method. In particular, the result can be (at least) that the gas has a property that is unsuitable for the gas-air combination and/or a component of the gas-air combination does not fit this application (type of gas) or was (basically) installed incorrectly. In particular, causes are identified that cannot be compensated for (permanently and/or over the entire modulation range) by a normal control system, but in particular require a manual (new) setup and/or replacement of the components (which adjust the flow) of the gas system. Air connection required. Issuing the cause may be accompanied by an instruction to restrict the operation of the gas-air system.

The flow reference values and the current flow values of the gas flow can record or relate to a volume flow. The volume flow can be recorded directly or indirectly using sensors. This can include detecting an auxiliary variable that depends on the volume flow or from which a volume flow can be derived.

The gas fitting can have an electronic controller, in particular a stepper motor. The controller or its operating parameters can be used to record or calculate the volume flow of the gas flow.

The method can be initiated in particular if it is determined that the electronic regulator of the gas fitting was previously without power or is only now being energized again. The fact that the gas fitting was decoupled from the electrical power supply can also be taken into account when identifying the cause of an identified deviation.

In the gas-air combination, means for detecting the type of gas can (also) be provided. As a means comes z. B. at least one sensor, a gas type-specific connection element, a gas type-specific software application, etc. into consideration.

The method can be initiated in particular when a change in the type of gas is detected or was detected shortly before. The fact that a

A change in the type of gas has been detected can also be taken into account when identifying the cause of an identified deviation.

In step d), a course of the deviation over a modulation range of the air flow can be evaluated. It is possible that the deviation of the values over a (considered or specified) modulation range is approximately constant, increases abruptly, (at times) continuously increases and/or decreases, oscillates around an average value with an amplitude, etc. The result of this evaluation can can be used for step e).

Depending on the result of step e), at least two different causes can be identified and output. In particular, the causes “wrong gas fitting” and “wrong gas type/gas family” can be identified and specified. It is possible that a variety of other causes can be identified in this way.

Step a) can be carried out taking historical flow values of the gas flow of the gas-air combination into account. So it is possible that e.g. B. corresponding flow reference values can be determined or adjusted via a learning process during the (previous) operation of the gas-air combination of the heater. The qualification as a permissible flow reference value can e.g. B. via flame detection.

While the method is being carried out, no (further) flow reference values of the gas flow are preferably generated or changed. For example, this can (only) be continued again if the procedure has been completed without any deviation being identified.

Following a further aspect, a gas-air combination of a heater is proposed, at least comprising an air line with a fan and a gas line a gas fitting, a regulation and control unit for setting an adjusted gas flow through the gas fitting while modulating the air flow and means adapted to carry out the steps of the method disclosed here.

The previous explanations of the gas-air combination of a heater or the method can be used to further characterize the device. In particular, the gas-air system of the heater can be set up so that it can carry out the method specified here.

In addition, a computer program is proposed, comprising commands that cause the gas-air combination disclosed here to carry out the steps of the disclosed method. The computer program can, for example, be intended for implementation in a regulation and control unit of a heater. This also includes a computer-readable medium on which the computer program is stored.

Fig. 1:

ein Beispiel eines elektrischen Gas-Luft-Verbundes eines Heizgerätes,

Fig. 2:

eine Veranschaulichung zur Gewinnung von Strömungsreferenzwerten, und

Fig. 3:

eine Bewertung einer Abweichung im Rahmen des hier offenbarten Verfahrens.

The solutions presented here and their technical environment are explained in more detail below using the figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in or in connection with the figures and to combine them with other components and/or findings from other figures and/or the present description. They show by way of example and schematically:

Fig. 1:

an example of an electric gas-air combination of a heater,

Fig. 2:

an illustration of how to obtain flow reference values, and

Fig. 3:

an assessment of a deviation within the framework of the method disclosed here.

Fig. 1 shows a gas-air combination 1 of a heater 2, which has an air line 3 with a blower 4 and a gas line 5 with a gas fitting 6. The gas fitting 6 includes an electrical regulator 7 which can be adjusted by a control and control unit 8 in such a way that an adapted gas flow through the gas fitting 6 is made possible with a modulation of the air flow that may also be predetermined or initiated by the control and control unit 8. Air line 3 and gas line 5 open into a common mixture line 9, which leads to a burner 10. The mixture is burned in the chamber surrounding the burner 10, and a flame monitor 11 can be provided there, which can transmit signals to the regulation and control unit 8 for the current flame formation. The exhaust gas from this combustion can be discharged via an exhaust pipe 12. The means are adapted so that they can carry out the steps of the method disclosed here.

Fig. 2 illustrates by way of example that an (ideal) target volume flow of the gas can be specified for a desired combustion quality when the air is modulated (left diagram in Fig. 2 ). With such a specification, the heater can be operated at the beginning, for example. Mathematically or ideally, a linear relationship results, as indicated by the dashed line on the right. However, this does not happen that way; rather, a system-related deviation can be identified. Nevertheless, a system-specific adjusted actual volume flow can be determined (e.g. by feedback from the flame monitoring results) at which the desired flame quality is actually achieved (right diagram in Fig. 2 ). These volume flow values can be recorded and made available as a flow reference value (SR).

In particular with a gas-air composite 1 according to Fig. 1 and according to that Fig. 2 Learned flow reference values SR, the following procedure can be carried out to evaluate the (successful or faulty) installation of the gas-air combination 1: a) Providing flow reference values SR of a gas flow through the gas fitting 6 when modulating the air flow by means of the fan 4; b) monitoring current flow values of a gas flow through the gas fitting 6 while modulating the air flow by means of the blower 4; c) determining a deviation of the current flow values of the gas flow from the flow reference values SR of the gas flow; d) assessing the deviation; and e) inferring a cause of the deviation.

Fig. 3 illustrates how this can be done, particularly in the context of steps d) and/or e). A diagram is shown there in which different curves of the flow values of the gas flow are shown over a predetermined modulation range M or the fan speed. The deviation from the ideal course is shown here as a percentage (see Fig. 2 right).

The (learned or historical) course V of the flow reference values SR is illustrated in the lower area. This includes a tolerance or permissibility range upwards and downwards, whereby the tolerance direction and/or width can be specified and/or also learned. This can therefore be provided as part of step a). If the currently recorded flow values S are at or at the flow reference values SR, it can be assumed that the installation is correct.

Above this, a first curve V of flow values S1 currently determined in step b) is illustrated. These are located at least in a partial area with a significant deviation A1 from the course V of the flow reference values SR, so that a deviation A1 is determined according to step c). According to step d), the deviation A1 can be evaluated such that it increases in the upper or right modulation range. In step e), this evaluation result leads to the conclusion that the cause is most likely an incorrect gas fitting 6 (with a locally changed design/geometry).

The diagram illustrates a second course V of flow values S2 currently determined in step b). These are located with a significant deviation A2 from the curve V of the flow reference values SR, so that a deviation A2 is determined according to step c). According to step d), the deviation A2 can be evaluated such that it is essentially constant in the modulation range. In step e), this evaluation result leads to the conclusion that the cause is most likely an incorrect type of gas (with constantly different burning behavior).

Reference symbol list

1

Gas-air combination

2

heater

3

Air line

4

fan

5

Gas pipe

6

gas fitting

7

electronic controller

8th

Regulation and control unit

9

Mixture line

10

burner

11

Flame monitoring

12

Exhaust pipe

S

Flow value

S.R

Flow reference value

A

deviation

M

Modulation range

v

Course

Claims (10)

Method for evaluating an installation of a gas-air combination (1) of a heater (2), which has an air line (3) with a blower (4) and a gas line (5) with a gas fitting (6), the method being at least includes the following steps: a) providing flow reference values (SR) of a gas flow through the gas fitting (6) when the air flow is modulated by means of the blower (4); b) monitoring current flow values (S) of a gas flow through the gas fitting (6) when modulating the air flow by means of the blower (4); c) determining a deviation (A) of the current flow values (S) of the gas flow from the flow reference values (SR) of the gas flow; d) assessing the deviation (A); e) Infer a cause of the deviation (A). Method according to claim 1, in which the flow reference values (SR) and the current flow values (S) detect a volume flow. Method according to one of the preceding claims, wherein the gas fitting (6) has an electronic controller (7), and the method is initiated when the electronic controller (7) was previously de-energized. Method according to one of the preceding claims, wherein means are provided for detecting the type of gas, and the method is initiated when a change in the type of gas has been detected. Method according to one of the preceding claims, in which in step d) a course (V) of the deviation (A) is evaluated over a modulation range (M) of the air flow. Method according to one of the preceding claims, in which at least two different causes are identified and output depending on the result of step e). Method according to one of the preceding claims, in which step a) takes into account historical flow values (S) of the gas flow of the gas-air combination (1). Method according to one of the preceding claims, in which no flow reference values (SR) of the gas flow are changed while the method is being carried out. Gas-air combination (1) of a heater (2), comprising at least an air line (3) with a blower (4), a gas line (5) with a gas fitting (6), a regulation and control unit (8) for adjustment an adapted gas flow through the gas fitting (6) with a modulation of the air flow and means adapted to carry out the steps of the method according to one of the preceding claims. Computer program comprising instructions which cause the gas-air combination (1) of claim 9 to carry out the steps of the method according to one of claims 1 to 8.

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