EP4343213A1 - Method for hydraulic balancing of a heating system - Google Patents

Abstract

The invention relates to a method (100) for carrying out hydraulic balancing of a heating system (10) with at least one heat generator (12), at least two heat exchangers (22, 24, 26) and at least two controllable heating valves (28, 30, 32), wherein Depending on the valve position (V) of a heating valve (28, 30, 32), the flow of a heat transfer medium through at least one heat exchanger (22, 24, 26) connected to this heating valve (28, 30, 32) can be controlled, comprising the steps: • Receiving (110) an increase in a target room temperature value for a room to which at least one of the heating valves (28, 30, 32) and a heat exchanger (22, 24, 26) is assigned, • Determining (120) the heat-up time (t< sub>N</sub>), which is needed to achieve a delta temperature increase (ΔT) in the room, • Determining (130) the heating gradient (∇_N) from the delta temperature increase (ΔT) and the heating time (t_N), • Determining (140) the mean relative valve position (V_{with_N}) of the heating valve (28, 30, 32) over the heating time (t_N),• Determine (150) the ratio (m_{erm_N}) of the heating gradient (∇_N) to the mean relative valve position (V< sub>mit_N</sub>),• Comparing (160) the determined ratio (m_{erm_N}) with at least one of the already determined ratios (m_bek) of at least one of the other heating valves (28, 30, 32), • Limitation (170) of the maximum valve position (V_max) of a heating valve (28, 30, 32) depending on the result of the comparison (160).

Description

The invention relates to a method for carrying out a hydraulic balancing of a heating system, a computer program, a machine-readable storage medium, an electronic heating control unit and a heating system

State of the art

There are different methods for carrying out hydraulic balancing in a heating system. These are often carried out manually and/or numerous additional sensors and other components are required that transmit the information required for hydraulic balancing to a control unit, which entails additional costs and additional effort. Furthermore, additional data about the heating system is required, which is often difficult to access. Electronic valves that are connected to a control unit are also used. The known methods are complex and computationally intensive. The known devices are complex.

An improved hydraulic balancing should be provided, which can be carried out in particular more cost-effectively, in particular automatically and/or in particular more easily.

Disclosure of the invention

This object is achieved by the method according to the invention for carrying out an automated hydraulic balancing of a heating system according to claim 1.

The heating system has at least one heat generator, at least two heat exchangers and at least two controllable heating valves, each with a changeable valve position. In particular, each heating valve has a valve means whose valve position can be changed. In particular, at least one heating valve is assigned to each heat exchanger.

The valve position is preferably changed using a magnetic drive or an electrically driven motor. Depending on the valve position, a flow opening and thus the flow of a heat transfer medium through the heating valve is controlled.

There is preferably at least one heating valve in the flow of a heat exchanger. Preferably, the flow through a heat exchanger can be controlled via at least one heating valve. The heating valve controls the flow of a heat transfer medium, which is heated or cooled in the heat generator, to at least one heat exchanger.

The method is characterized in that an increase in a target room temperature value for a room is received in one method step. Receiving also includes, in particular, retrieving, querying or measuring. The target room temperature value is preferably a trigger which is intended to trigger the further steps. If the target room temperature is changed, the process in particular, i.e. the further process steps, is carried out. In particular, the change in the target room temperature value represents an event that causes heating. A target room temperature value is preferably also to be understood as a target room temperature.

A room can also be a part or area of a building.

At least one of the heating valves and a heat exchanger are assigned to the room. The heat exchanger is designed in particular as a heat exchanger. It releases the heat, which is transported with the heat transfer medium, into the environment. This causes the surrounding air in particular to heat up. In particular, assigned means that the heat exchanger is arranged in such a way that it can transfer heat to the room. In particular, the associated heat exchanger serves to heat the room, in particular the air in the room.

The method further includes determining the heating time required to achieve a delta temperature increase in the room. In particular, a delta temperature increase is defined and preferably does not change. The heating time is determined until the actual room temperature has reached the target temperature. The target temperature corresponds to the initial room temperature, in particular the actual room temperature, plus the delta temperature increase. In particular, the cell temperature can be smaller than the target temperature. In particular, determining the heating time includes measuring the time.

The method also includes determining the heating gradient from the delta temperature increase and the determined heating time. The heating gradient is determined by dividing the delta temperature increase by the heating time. The heating gradient is preferably assigned to the heating valves of a room. In particular, determining includes calculating.

In a further method step, the average relative valve position of the heating valve is determined during the heating-up period, i.e. the heating-up time. In particular, the average value is calculated from all valve positions that the heating valve had over the heating time. The duration for which a valve position was set is preferably taken into account.

In one process step, the relationship between the heating gradient and the mean relative valve position is determined. The ratio is determined in particular by dividing the heating gradient by the determined mean relative valve position.

The method also includes the step of comparing the determined ratio with the already determined ratios of at least one, in particular all, of the other heating valves. The ratios that have already been determined are also referred to as known ratios. Known ratios are the last determined ratios of a heating valve that were not determined in the current process run. Preferably at least one, in particular all, of the conditions already determined is used. In particular, only the most recently determined conditions of a heating valve are used.

In one method step, the maximum valve position of a heating valve is limited depending on the result of the comparison of the ratio of the heating valves. In particular, the heating valve whose ratio was last determined does not have to be limited or only the heating valve needs to be limited.

A heat generator is a unit that can provide heat. The heat provided can be transferred to a heat transfer medium, such as gas, a fluid or the like. Examples of heat generators are a gas or oil burner, a solar system, a heat pump, a pellet stove or an air conditioning unit. Water is often used as the energy-transferring heat transfer medium.

A heat exchanger is a unit or body, such as a device or a comparable device, which can store thermal energy and release it to a medium such as objects, liquids or gases. Examples include a radiator, underfloor heating, indoor air conditioning unit and the like.

The flow of the heat transfer medium depends on the valve position of the heating valve. Depending on the valve position, the flow opening of the heating valve is varied between a minimum and a maximum. In particular, the valve position can be limited mechanically or electrically. The flow can preferably be limited in this way.

The term flow opening refers to an opening of a line, in particular the total area of the opening, and/or an opening of a heating valve through which a fluid can pass. A heating valve usually has a valve means or the like. The valve means can be used to close and/or open a flow opening of one or more lines. A valve position of the heating valve means the position of the valve means. Depending on the valve position, the size of the flow opening is changed, in particular reduced or increased.

The connection between the at least one heat generator, the at least two heat exchangers and the at least two heating valves is a hydraulic connection. With the hydraulic connection, the components mentioned are located in one or more heating circuits. The at least one heat generator and the at least two heat exchangers can also be connected electronically. In order to carry out the automated hydraulic balancing, there does not have to be an electronic or control connection between the valves themselves.

Preferably, a heating valve and a heat exchanger, which are assigned to one another, are hydraulically connected to one another. Preferably, the heating valve is connected upstream of one or more heat exchangers. There is also the possibility that the heating valve is connected downstream.

A heating time is to be understood as the time that is required to bring a room from an initial temperature by a delta temperature increase, in particular between 0.2 and 1K, preferably 0.5 and 0.7K, for example 0.6K, to a target temperature to heat up. In particular, other delta temperature increases are also possible, preferably less than 5K, for example less than 2K.

The heating time of a room means the time that is required to heat the heat exchanger or the room from an initial temperature, in particular the actual temperature, to a delta temperature increase to a target temperature.

A heating system is said to be hydraulically balanced if the amount of heat available or generated is optimally distributed across all heat exchangers. Normally, each heat exchanger should have exactly the heat available that it needs to heat a room to a specific temperature.

A maximum valve position is the maximum valve position that is permitted so that the heating system is hydraulically balanced, which means that each of the existing heat exchangers is optimally supplied with heat.

The features listed in the subclaims make advantageous developments of the method according to the invention possible according to the main claim.

An advantageous development of the method is characterized in that the maximum valve position of a heating valve or several heating valves is limited when the comparison shows that the determined ratio of the heating valve is greater than a defined tolerance compared to at least one further determined ratio. In particular, the heating valves that are outside the tolerance are adjusted.

According to an advantageous development, the valve position or the flow temperature of the heat transfer medium is changed. Preferably, the increase in the target room temperature value causes the heating valve(s) assigned to the room to change their valve position, in particular in such a way that the flow rate of the heat transfer medium is increased. Preferably the flow opening is enlarged. Alternatively or additionally, the flow temperature of the heat transfer medium is increased.

An advantageous further development is that the delta temperature increase is between, in particular, 0.2 and 1K, preferably 0.5 and 0.7K, for example 0.6K. The values have proven to be advantageous because the warm-up does not take too long, but small temperature fluctuations due to external influences do not come into play.

An advantageous development is that when comparing, the minimum ratio or the average ratio is determined from all determined or known ratios. The average ratio is the average of all known ratios and the determined ratios of the different heating valves. Preferably, the heating valves that are limited are selected based on the determined minimum ratio or average ratio.

An advantageous development is that when limiting the heating gradient is determined using the minimum ratio and/or the average ratio, and that the maximum valve position for at least one, in particular all heating valves is determined using the determined heating gradient.

An advantageous development of the method is characterized in that the ratio is determined for each heating valve. Preferably, the ratio and thus a maximum valve position is determined for each heating valve. In particular, the maximum valve position can be determined by increasing the target temperature value for the test in a test mode. In particular, the target temperature value can be increased in series or in parallel.

An advantageous further development is that the ratio for heating valves that are assigned to one and the same room are determined at the same time.

An advantageous further development is that the maximum valve position of a heating valve cannot be set below, in particular only above, a limit value of 50%, preferably 40%, for example 30%, of the maximum technically possible valve position of the heating valve. Preferably, the maximum valve position is determined to be below the limit value the limit value is set. This prevents a heat exchanger from only being supplied with minimal or no heat energy at all. This can happen in particular if the heating system has a fault or, in particular, a large number of the heating valves are broken.

The invention relates to a computer program which is set up to carry out all steps of the method.

The invention further relates to a machine-readable storage medium on which the computer program is stored.

The invention further relates to an electronic heating control unit which is set up to carry out the steps of the method.

The invention further relates to a heating system which can be hydraulically adjusted using an automated method.

drawing

Figur 1

eine erfindungsgemäße Heizungsanlage

Figur 2

ein erfindungsgemäßes Verfahren und

Figur 3

das Verfahren anhand eines Koordinatensystems.

The figures show a schematic representation of a heating system according to the invention as well as a valve and method according to the invention, which are explained in more detail in the following description. Show it

Figure 1

a heating system according to the invention

Figure 2

a method according to the invention and

Figure 3

the method using a coordinate system.

Figure 1 shows a heating system 10 according to the invention. This has a heater 12, a heating circuit 14 with a flow 16, a return 18 and a pump 20 for circulating a heat transfer medium, in particular a gas or fluid, for example water, through the heating circuit 14. In the heating circuit 14 there are, for example, three heat exchangers 22, 24, 26 first heat exchanger 22, a second heat exchanger 24 and a third heat exchanger 26.

The heat exchangers 22, 24, 26 can in particular be designed as radiators or underfloor heating. One of the heat exchangers can also be designed as a radiator and another as underfloor heating. Preferably, at least one heat exchanger is formed in each room. However, it is also conceivable that two or more heat exchangers are arranged in one room. It is also conceivable that there are rooms without heat exchangers.

A heating valve 28, 30, 32 is arranged in the flow of each heat exchanger 22, 24, 26. In Figure 1 A first heating valve 28, a second heating valve 30 and a third heating valve 32 are shown as examples. These are electronic heating valves 28, 30, 32, for example electronic thermostat valves. A heating valve 28, 30, 32 is assigned to each heat exchanger 22, 24, 26.

According to an advantageous development, several heat exchangers 22, 24, 26 can also be assigned to a heating valve 28, 30, 32. The heat exchangers 22, 24, 26, which are assigned to a heating valve 28, 30, 32, can be connected to one another in series and/or parallel. Preferably, a heating valve 28, 30, 32 can control the flow of the heat transfer medium through one or more heat exchangers 22, 24, 26. Preferably, several heating valves can also be connected upstream of one or more heat exchangers 22, 24, 26, which are arranged in the same room.

The heater 12 usually has a heating control unit 40 for control and/or regulation. Preferably, heating control unit 40 can also control the flow temperature of the heat transfer medium by means of heater 12.

The room controllers 42, 44, 46 are preferably designed. The room controllers 42, 44, 46 preferably have a control element and a Display means, in particular a display. They allow you to set a target room temperature. The room controllers 42, 44, 46 are preferably assigned to a room for which the target room temperature can be set. According to an advantageous development, it is possible to set several target room temperatures using a room controller 42, 44, 46.

The room controller 42, 44, 46 can also be integrated into the heating control unit 40.

The room controllers 42, 44, 46 are also designed to control the heating valves 28, 30, 32. For this purpose, there is a control connection between the room controllers 42, 44, 46 and the heating valves 28, 30, 32. This can be wireless or wired.

According to an advantageous development, the room controller is integrated into the heating valve. In particular, the heating valve has, for example, a display means and an operating element.

The heating valves 28, 30, 32 can also be controlled directly via the heating control unit 40. For this purpose, there is a control connection between the heating control unit 40 and the heating valves 28, 30, 32. This can be wireless or wired.

The possible control connections are exemplary in Figure 1 shown in dashed lines.

The heating control unit 40 is designed to carry out a method 100 according to the invention. The heating control unit 40 has a communication means that allows it to receive or send target temperature values and actual temperature values. Preferably, the heating control unit 40 is connected to the heating valves 28, 30, 32 by means of control connections. Preferably, the heating control unit 40 is connected to the heater by means of a control connection.

According to an advantageous development, the method 100 is carried out distributed among the room controllers and/or the heating valves.

The target room temperature value can also be set using a mobile device, in particular a smartphone or a tablet. For this purpose, the target room temperature value is sent in particular to a room controller, a heating valve or the heating control unit 40.

A temperature sensor (not shown) is preferably designed to detect the actual temperature in a room. The actual temperature value is required in particular to carry out the process. The temperature sensor is required to record the current temperature in a room. The temperature sensor makes the detected temperature available to the heating control unit 40 and/or a room controller and/or a heating valve 28, 30, 32. In particular, the room controllers have the temperature sensor. You can send the actual temperature to the heating control unit 40. Preferably, several temperature sensors are provided, which are each assigned to a heating valve.

Figure 2 shows a method 100 according to the invention for carrying out an automated hydraulic balancing. The method 100 includes several method steps. The order in which the process steps take place can sometimes be reversed.

In a method step 110, an increase in a target room temperature value is received. The change in the target room temperature value can be generated by a user, in particular a resident, but also by an automated system. It can also be triggered automatically or triggered by a time program. Receiving also includes retrieving, querying or measuring a changed target room temperature value. The change in the target room temperature value acts like a trigger, which triggers the further process steps.

Room controllers 42, 44, 46, in particular with a thermostat function, preferably offer the possibility of changing the target room temperature. A room controller 42, 44, 46 is preferably assigned to a room. In particular, a room controller 42, 44, 46 is also arranged in the room to which it is assigned. The room controller 42, 44, 46 preferably has a display means and an operating element. Room controllers are also colloquially referred to as thermostats. In particular, the room controllers also have temperature sensors for recording the actual temperature.

According to a further development, a central room controller is designed. This makes it possible to set the target room temperature values for two or more rooms. The heating control unit 40 and the central room controller are preferably designed as a unit.

The increase in the target room temperature, in particular the target room temperature value, causes an increased temperature in the room to be desired. In order to achieve this, heat energy must be supplied to the room and/or the heat energy supplied must be increased.

According to a first embodiment, the additional supply of thermal energy takes place by changing the valve position of at least one of the heating valves 28, 30, 32 that are assigned to the room. If more than one heating valve 28, 30, 32 is assigned to the room, their valve position is also changed. Preferably, the valve position of all heating valves 28, 30, 32 assigned to the room is changed. The valve position is preferably changed in such a way that the flow of the heat transfer medium increases. The flow of heat transfer medium in one or more heat exchangers 22, 24, 26, which are connected downstream of the heating valve 28, 30, 32, in particular whose valve position has been changed, also increases accordingly.

Heating valves assigned to a room are to be understood in particular as heating valves which have at least one heat exchanger is assigned to the room, are connected upstream and / or control the flow through the at least one heat exchanger.

According to a second embodiment, the flow temperature of the heat transfer medium is increased. Increasing the flow temperature causes more thermal energy to be supplied to the heat transfer medium. The flow temperature is increased in particular by the heater 12.

In a further method step 120, the heating time t _N is determined. The time required to heat the room from an initial temperature, also referred to as the actual room temperature, by a delta temperature increase ΔT is determined. Preferably, the time is determined to increase the temperature in a room from the actual room temperature by a delta temperature increase ΔT to a target temperature.

Preferably, the target temperature must be less than or the same as the target room temperature. Such a check is carried out in the optional method step 115. If the target temperature is smaller than the target temperature, the method 100 is aborted.

In the following, N stands for a heating valve. Using the example of Figure 1 is N = 1, 2 or 3. In particular, for example, N = 1 stands for the heating valve 28, N = 2 stands for the heating valve 30 and N = 3 stands for the heating valve 32. Preferably, the method 100 is repeated at least according to the number of heating valves .

In a further method step 130, the heating gradient ∇ _N is determined. The heating gradient ∇ _N is determined from the delta temperature increase ΔT _N and the heating time t _N. $${\nabla }_{\mathrm{N}}=\Delta {\mathrm{T}}_{\mathrm{N}}/{\mathrm{t}}_{\mathrm{N}}$$

In a further method step 140, the mean relative valve position V _{mit_N} is determined. The mean relative valve position V _{mit_N} is the middle one Valve position over the heating time t _N . It is determined in particular by means of a time-weighted averaging of the valve positions ∇ _N during the heating time t. In particular, the mean relative valve position V _{mit_N} is determined by the heating valve N, which is assigned to the room.

In a further method step 150, the ratio m _{erm_N} from the heating gradient ∇ _N to the mean relative valve position V _{mit_N} is determined. $${\mathrm{m}}_{\mathrm{erm\_N}}={\nabla }_{\mathrm{N}}/{\mathrm{v}}_{\mathrm{with\_N}}$$

Preferably, a low-pass filter is additionally applied to the determined ratio m _{erm_N} in order to minimize the influence of disturbance variables. In a heating system 10, which is hydraulically balanced, it is advantageous that the ratio m _{erm_1} of a first heating valve is equal to the ratio m _{erm_2} of a further heating valve is. In particular, one speaks of hydraulically balanced if the value m differs only minimally. For example, if the ratio m _{erm_1} of a first heating valve is 1.0 and the ratio m _{erm_2} of a second heating valve is also 1.0 or 1.01, then the heating system consisting of the two heating valves is hydraulically balanced. If there are more than two heating valves, m _{erm_1} = m _{erm_2} = m _{erm_N} of all heating valves must be essentially the same or must not exceed a defined deviation, in particular tolerance T _def . If the defined deviation is exceeded, it is a heating system 10 that is not hydraulically balanced.

In a method step 160, the determined ratio m _{erm_N} , in particular also referred to as m _{erm_N} , is compared with the determined ratios m _bek of one or more other heating valves or rooms. In particular, the m _erm values of the heating valves are each stored in a separate memory as m _bek after the determination.

The ratio m _bek that was last determined for another heating valve is preferably used. Preferably the conditions will be m _erm all Heating valves determined. Preferably, the comparison is carried out again with one or more, in particular all, m _bek after each determination of m _{erm_N} . Preferably, in particular subsequently, the determined m _{erm_N} is stored as m _bek for this valve in a memory.

According to an advantageous development, the heating valve with the lowest ratio m is determined in method step Compare 160. The smallest m is also called m _min . All known m _bek and the newly determined m _{erm_N} are used.

Furthermore, the heating gradient ∇ _min is determined for the heating valve with the lowest ratio m _min for a valve position of 100%, i.e. maximum open. The heating gradient ∇ _min is preferably calculated for 100% valve position. $${\nabla }_{\min }=\left({\mathrm{m}}_{\min }\right)\ast 100\%$$

In a method step 170, the maximum valve position of a heating valve 28, 30, 32 or more heating valves is limited. The heating valve N does not necessarily have to be limited here, for which the ratio m _{erm_N} is determined in one of the directly preceding method steps.

In method step Limit 170, the maximum valve position V _max of one or more heating valves is specified. The maximum valve position V _max is determined for each heating valve from the determined heating gradient ∇ _min .

According to a further development, the heating valve or valves are limited, the ratio m of which lies outside the permissible tolerance Tol. If more than one heating valve 28, 30, 32 is outside the Tol tolerance, several heating valves 28, 30, 32 can also be limited. $$\mathrm{v}=\mathrm{f}\left({\mathrm{m}}_{\mathrm{Bek}},\mathrm{Great},{\mathrm{m}}_{\mathrm{erm\_N}}\right)$$

According to a further development of the invention, the heating gradient ∇ _min of the heating valve with the lowest m, the m _bek and the m _{erm_N} is not used, but rather the heating gradient ∇ _min is calculated _using the average ratio m minus the standard deviation σ. The average ratio m _with is the average of all known ratios m _bek and the determined ratios m _{erm_N} of the different heating valves. The 100% is necessary to determine the heating gradient V for a completely open valve. With a valve position of V=100% this results. $${\nabla }_{\min }=\left({\mathrm{m}}_{\mathrm{with}}-\mathrm{\sigma }\right)\ast 100\%$$

This can advantageously compensate for design errors in particular, such as heat exchangers that are too small. Broken or faulty valves can also be compensated for.

The standard deviation σ is a measure of the spread of the values of a characteristic around its mean (arithmetic mean). Put simply, the standard deviation is the average distance of all measured expressions of a characteristic from the average. In this way, valves that are faulty or faulty heating system designs can be excluded. Faulty valves would cause the heating valves to be incorrectly limited.

oder $${\mathrm{V}}_{\max }={\nabla }_{\min }/{\mathrm{m}}_{\mathrm{bek}}$$

The maximum valve position of a heating valve is limited by dividing the determined heating gradient ∇ _min by the ratios m _{erm_N} or known ratios m _bek determined for the heating valve. $${\mathrm{v}}_{\mathrm{max\_N}}={\nabla }_{\min }/{\mathrm{m}}_{\mathrm{erm\_N}}$$

or $${\mathrm{v}}_{\mathrm{Max}}={\nabla }_{\min }/{\mathrm{m}}_{\mathrm{Bek}}$$

Preferably, method step 170 is repeated, in particular for each heating valve. The new maximum valve position is determined for each heating valve. For each heating valve either the one known from it is used Ratio or, if necessary, the ratio newly determined for the heating valve in the process steps is used.

In Figure 3 Parts of the method 100 are explained using a coordinate system. The valve position V is shown on the x-axis. The heating gradient V is plotted on the y-axis.

The dashed lines represent the course of the ratio m ₁ of a first heating valve 28 and the dashed lines represent the course of the ratio m ₂ of a second heating valve 30.

As an example, m ₁ was previously determined and is therefore comparable to m _{erm_N} , here m _{erm_1} . m ₂ corresponds to the m _bek of the heating valve 2.

According to method step 160, the heating valve with the lowest ratio m _min is determined 160a. According to the example Figure 3 This is the first heating valve 28. The determination is carried out in particular by comparing.

Furthermore, the heating gradient ∇ _min for the heating valve with the lowest ratio m _min for a valve position V = 100%, i.e. maximally opened, is determined 160b. Preferably the ratio is calculated for 100% valve position. 160a and 160b are substeps of 160.

The maximum valve position is then limited 170.

The determined heating gradient ∇ _min is specified to one or all other heating valves 170a. The maximum valve position V _max and/or V _{max_N} for the heating valves is determined from the specified heating gradient ∇ _min 170b. Preferably in the example according to Figure 3 the second heating valve 30 is limited. 170a and 170b are substeps of 170.

According to a further development of the invention, the heating gradient ∇ _min is not used, but the calculation is made using the average heating gradient ∇ _with all heating valves minus the standard deviation σ. This can be particularly advantageous when it comes to design errors, such as those that are too small Heat exchanger, to be balanced. Broken or faulty valves can also be compensated for.

Claims (13)

Method (100) for carrying out hydraulic balancing of a heating system (10) with at least one heat generator (12), at least two heat exchangers (22, 24, 26) and at least two controllable heating valves (28, 30, 32), depending on the Valve position (V) of a heating valve (28, 30, 32) the flow of a heat transfer medium can be controlled through at least one heat exchanger (22, 24, 26) connected to this heating valve (28, 30, 32), comprising the steps: • Receiving (110) an increase in a target room temperature value for a room to which at least one of the heating valves (28, 30, 32) and a heat exchanger (22, 24, 26) is assigned, • Determining (120) the heating time (t _N ) that is needed to achieve a delta temperature increase (ΔT) in the room, • Determine (130) the heating gradient (∇ _N ) from the delta temperature increase (ΔT) and the heating time (t _N ), • Determining (140) the mean relative valve position (V _{with_N} ) of the heating valve (28, 30, 32) over the heating time (t _N ), • Determine (150) the ratio (m _{erm_N} ) of the heating gradient (∇ _N ) to the mean relative valve position (V _{mit_N} ), • Comparing (160) the determined ratio (m _{erm_N} ) with at least one of the already determined ratios (m _bek ) of at least one of the other heating valves (28, 30, 32), • Limitation (170) of the maximum valve position (V _max ) of a heating valve (28, 30, 32) depending on the result of the comparison (160). Method (100) according to the preceding claim, characterized in that the maximum valve position (V _max ) of a heating valve (28, 30, 32) is limited when the comparison (160) shows that the determined ratio (m _{erm_N} ) or one of the known ratios (m _bek ) of the heating valves (28, 30, 32) differs from one another greater than a defined tolerance (T _def ). Method according to one of the preceding claims, characterized in that the heating valve or valves (28, 30, 32) assigned to the room change their valve position or the flow temperature of the heat transfer medium is changed. Method according to one of the preceding claims, characterized in that the delta temperature increase (ΔT _N ) is between in particular 0.2 and 1 K, preferably 0.5 and 0.7K, for example 0.6K. Method according to one of the preceding claims, characterized in that during comparison (160) the minimum ratio (m _min ) or the average ratio (m _with ) is determined from all determined or known ratios. Method according to one of the preceding claims, characterized in that when limiting (170) the heating gradient (∇ _min ) is determined by means of the minimum ratio (m _min ) and/or the average ratio (m _with ), and that by means of the determined heating gradient ( ∇ _min ) the maximum valve position (V _max ) is determined for at least one of the heating valves. Method according to one of the preceding claims, characterized in that the ratio (m _{erm_N} ) is determined for each heating valve (28, 30, 32). Method according to one of the preceding claims, characterized in that the ratio (m _{erm_N} ) for heating valves (28, 30, 32) that are assigned to one and the same room are determined simultaneously. Method according to one of the preceding claims, characterized in that the maximum valve position (V _max ) cannot be set below a limit value of 50%, preferably 40%, for example 30%, of the maximum technically possible valve position of the heating valve (28, 30, 32). Computer program which is set up to carry out all steps of the method claims 1 to 9. Machine-readable storage medium on which the computer program according to claim 10 is stored. Electronic heating control unit which is set up to carry out all steps of the method according to claims 1 to 9. Heating system, which can be hydraulically adjusted automatically using a method according to one of claims 1 to 9.

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