EP1780472A2 - Assembly for supplying water to heating systems with water heating device - Google Patents

Abstract

The construction group (10) includes a fresh water inlet (14) for connecting to the water heater, a first outlet (16) and a shut-off valve (32) for the fresh water inlet. It also has a second outlet (26) for connection to the heating circuit. A separator is provided between the fresh water inlet and the second outlet for the physical separation of the water supply from the heating circuit.

Description

Technical area

The invention relates to an assembly for supplying water to heating systems with water heater, comprising a fresh water inlet for connection to a water supply port, a first outlet for connecting a water heater and shut-off means for shutting off the fresh water inlet.

Drinking water heaters are usually heat insulated containers. The container is connected on the one hand with a drinking water system and on the other hand with a domestic water system. The domestic water system has taps for heated drinking water. The warming of the drinking water is carried out by means of a hot water from a hot water heater flowing through the heat exchanger.

The module connects a heating system with DHW heating to the water supply. For maintenance or replacement of the heating system, a stopcock is provided. So it does not need the entire water supply of a building to be shut off. Known assemblies for supplying the Trinkwasserwasserwärmers with fresh water have the disadvantage that the temperature of the withdrawn hot water can depend on the inlet pressure of the fresh water supply. Especially with smaller gas heaters, the heating power for large amounts of water may not be sufficient. At high pressures, the temperature of the hot water drops.

The heating water, on the other hand, is circulated in a separate, closed circuit, the heating circuit. The water is heated, flows to the radiators (supply) and releases its heat in the radiators. The water flows back to the heating system via the return line.

By venting it can lead to pressure reduction. Then the pressure in the heating circuit drops. Accordingly, the heating circuit must be refilled at regular intervals.

State of the art

Known heating systems have a fresh water connection, which is connected via an assembly listed above with the domestic water system. Regardless of this fresh water connection (drinking water system), the filling and refilling of the heating circuit is completely separate. It must be prevented under all circumstances that, for example in a pressure drop in the drinking water system, water from the heating circuit flows back into the drinking water system. Special safety regulations apply here, e.g. the EN 1717.

Filling or refilling is possible via so-called system separators. Such a system separator is known, for example, under the name "FüllCombi BA 6628" by the applicant. It is a system with two backflow preventers. These are spring-loaded check valves, which open under the influence of drinking water pressure only in the direction of the drinking water system to the heating circuit. However, this is not considered sufficient for continuous operation. With an input-side pressure drop, there is a physical separation between the drinking water system and the heating circuit. The known system separator replaces the previously used in old heating systems hose, which is removed after completion of the filling or refilling process. Between the backflow preventer a differential pressure controlled relief valve is arranged. When the pressure difference between the drinking water system and the heating circuit drops below a predetermined value, the relief valve opens automatically. When the heating circuit is filled from the drinking water system or is refilled and there is sufficient drinking water pressure, then the relief valve is closed. It flows through the drinking water pressure on the backflow preventer into the heating circuit.

The known system separator operates "semi-automatically", i. at a pressure drop, e.g. is displayed on a manometer, an input-side shut-off valve must be opened and the filling or refilling process to be triggered. After completion of the filling process, the valve is closed manually again. However, automatic arrangements are also known, e.g. under the trade name "reflex 'fillcontrol'" of Reflex Winkelmann GmbH + Co. KG, Gersteinstrasse 19, D - 59227 Ahlen. This arrangement is equipped with its own pressure sensor, which monitors the pressure in the heating circuit. The shut-off valve is motor-controlled.

The known filling combinations comprise a plurality of components and are bulky. They are therefore installed in conventional heating systems spatially outside of the boiler and connected separately via the standard safety equipment with the drinking water network.

Disclosure of the invention

It is an object of the invention to simplify the connection fittings in existing boiler designs and make them more compact.

According to the invention the object is achieved with an assembly of the type mentioned by a second, provided with shut-off for connection to the heating circuit of the heating system, and arranged between the fresh water inlet and the second outlet system separator for physically separating the water supply from the heating circuit means two backflow preventer and arranged between the backflow preventer, differential pressure controlled drain valve.

In this way, only a fresh water connection for the provision of fresh water in the drinking water heater, as well as for filling or refilling the Heating circuit used via a system separator. The intended fresh water inlet of the assembly requires only a stopcock for the inlet of the DHW cylinder and the boiler filling during maintenance. Accordingly, the arrangement requires less space. A separation between arrangements for refilling and filling the heating circuit is no longer necessary.

In a particularly preferred embodiment of the invention, a pressure reducer is provided, via which the water pressure can be adjusted at both outlets. The pressure reducer can be arranged, for example, immediately behind the shut-off at the fresh water inlet. It then has two functions: on the one hand, it ensures a constant water pressure in the DHW cylinder. A change in the hot water temperature at the taps due to pressure fluctuations is avoided. On the other hand, the inlet pressure in the system separator and in the filling line of the heating circuit is kept constant. This will set the heating pressure.

With the dual functionality of the upstream shut-off and the pressure reducer, fewer components are required compared to using two separate assemblies. The arrangement is therefore more economical and compact and can be integrated directly into the heating system due to the small dimensions.

In one embodiment of the invention, the further shut-off means for shutting off the connection to the heating circuit are formed by a normally closed solenoid valve. The valve is closed even in the event of a fault. No water can pass into the heating circuit or in the opposite direction. There may be provided control and regulating means for controlling the flow of water into the heating circuit by means of the further shut-off means in response to the signal of a pressure sensor provided in the heating circuit. In this case, the existing in the heating system anyway pressure sensor can be used. In contrast to known filling groups, no separate pressure sensor is required. In this way, an automatic refilling is very easy. The already existing in the heating system control can be programmed so that they Control signal for the solenoid valve supplies. When the pressure sensor in the heating circuit detects a low water pressure, a control signal is given to the solenoid valve. The valve opens and water from the fresh water supply can flow into the heating circuit. When the pressure sensor delivers a signal with sufficient water pressure, the valve is closed again.

In a preferred embodiment of the invention, the housing has an elongated shape and thus forms a housing longitudinal axis. The side of the housing, the fresh water inlet and the first outlet are respectively provided. The backflow preventer are arranged in alignment with the housing longitudinal axis in the housing and accessible via a nozzle at the end of the housing for maintenance and testing purposes. This arrangement is particularly compact and is well suited for installation in existing heating systems. The arrangement meets all the requirements of EN 1717 for a system separator.

Preferably, the assembly includes a housing having a heating circuit inlet which, together with the second outlet, forms part of the heating circuit. Between the heating circuit inlet and the second outlet blocking means may be provided for shutting off the heating circuit. Such a barrier is required for maintenance purposes, for example. The shut-off means for shutting off the heating circuit can be formed by a ball valve, the ball is in a volume between the heating circuit inlet and second outlet, said volume is connected via the further shut-off and the system separator with the fresh water inlet. Preferably, a drain valve is provided, via which the heating circuit can be emptied.

In a particularly preferred embodiment of the invention, means for monitoring the amount of water supplied to the heating circuit are provided and display means for indicating a fault when the amount of water supplied is outside an allowable range. All necessary functionalities of a heating circuit are integrated into the module. The arrangement is still very compact and can be integrated directly into a heating system with water heater.

Embodiments of the invention are the subject of the dependent claims. An embodiment is explained below with reference to the accompanying drawings.

Brief description of the drawings

Fig. 1

is a plan view of an assembly for supplying water to a heating system with drinking water heater.

Fig.2

is a side view of the assembly of FIG. 1 from the left in Fig.1.

Figure 3

is a rear view of the assembly of Figures 1 and 2 from the left in Fig.2.

Figure 4

is a horizontal section through the assembly of Fig. 1 to 3.

Figure 5

is a vertical section along the section line A-A in Figure 4.

Figure 6

is a vertical section along the section line C-C in Figure 4.

Figure 7

is a vertical section through an assembly with a system separator with test connections.

Description of the embodiment

In Fig.1 a generally designated 10 assembly for connecting a heating system (not shown) to a drinking water supply is shown. The drinking water supply is from a drinking water network. At an inlet in the form of an inlet nozzle 14, the assembly 10 is connected to the drinking water network. The water flows in the direction of arrow 12.

Furthermore, the assembly has a first outlet in the form of an outlet 16. The outlet 16 is connected to a drinking water heater. The drinking water can flow in the direction of the arrow 18 from the outlet to the drinking water heater (not shown). As a drinking water heater in particular a wall-mounted gas boiler is provided here.

The assembly 10 includes an elongated housing 20 to which the sockets 14 and 16 are formed at a right angle. At one end of the housing 20, an opening 22 is provided which is closed with a plug. A likewise perpendicular from the housing 20 outgoing nozzle 26 which is parallel to the outlet 16, is the outlet for a heating circuit. A flush with the outlet 26 connecting piece 28 form the inlet for the heating circuit. In the present case, the assembly is arranged in the return of the heating circuit. A drain 30 (Figures 2 and 3) is provided for draining the heating circuit.

The module can be integrated as a whole in a heating system. The outlets 18 and 26 are arranged and dimensioned so that they can easily be connected to existing connections without manipulating the heating system itself. The assembly thus replaces the separate components and fittings for the heating circuit and the fresh water connection.

The functionality of the assembly 10 will now be explained in more detail with reference to FIGS. 4 to 6: behind the inlet 14, a ball valve 32 is provided downstream. The inlet 14 is shut off with a ball valve 32 by means of a tool (not shown). 4 and 6, the ball valve 32 is shown in the open position. The Water flows through the open ball valve 32 and then down through a passage 34 (Fig.4). The passage 34 opens into the inlet region 36 of a pressure reducer 38 integrated in the assembly. The pressure reducer 38 is seated in a housing part 42 which is closed by a cover 40. The pressure reducer 38 can be pulled out of the housing part 42 in a cartridge-like manner for maintenance purposes in this way. The pressure reducer 38 ensures a constant inlet pressure at the following components.

From the pressure reducer 38, the water flows into a cavity 58 in the elongated housing part 20. The cavity 58 is connected to the outlet 16. Via a plug 54 with webs 52 as a spacer, the cavity is accessible. The water can flow directly from the inlet 14 via the pressure reducer 38 to the outlet 16. There it is available for DHW heating.

In the elongate housing 20, a cylindrical chamber 70 is formed. The cavity 58 is connected to this cylindrical chamber 70. There is a system separator with a differential pressure controlled relief valve and two backflow preventers 62 and 64 are arranged.

The relief valve 60 includes a piston-shaped valve body 66. The valve body 66 is guided in the chamber 70. It closes against the spring pressure of a spring 72 an outgoing from the chamber 70 drain 68 when the inlet pressure is sufficiently high. The drain 68 has a drain connected to the atmosphere.

The valve body 66 is sealingly guided in its cylindrical surface 74 with a seal 76 in the cylindrical chamber 70. At its downstream end face 78, the valve body 66 forms an annular valve seat. The valve seat abuts a seat seal 80 in the downstream end position (not shown). With the lateral surface 74 of the valve body 66 covers the drain 68. This is the drain valve.

The valve body 66 has a central passage. In the passage sits the upstream non-return valve 62. Seated in the housing of the backflow preventer a valve seat. The valve seat cooperates with a valve closing body which opens against the pressure of a coil spring in the downstream direction when a sufficient inlet pressure is applied.

The coil spring 72 is supported on a shoulder 82 on the inside of the housing 20 and abuts upstream on the downstream, rear side of the valve body 66. As a result, the valve body 66 of the drain valve is loaded by the spring 72. The spring 72 ensures that the drain valve is always open without further forces.

Downstream of the arrangement described, a backflow preventer 64 is seated in the fitting housing. The backflow preventer 64 is basically similar in construction to the upstream backflow preventer 62 and therefore not described in detail. Both backflow preventers 62 and 64 open only in the direction from the inlet pressure to the outlet pressure. Between the valve body 66 and the downstream backflow preventer 64, a medium-pressure space 70 is formed.

The coil spring of the backflow preventer 62 is stronger than the coil spring 72 acting on the valve body 66. Therefore, the backflow preventer 62 opens only when the valve body 66 is moved to its downstream end position by the pressure difference between inlet pressure and the mean pressure prevailing in the medium-pressure space. In this way, when the passage to the outlet port with respect to the outlet 68 and the atmosphere is completed, the backflow preventer is pressed by the water pressure. The heating system is filled to an outlet pressure slightly below the inlet pressure.

The discharge valve body 66 has a diameter on the input side that corresponds to the inner diameter of the elongated housing 20. The drain valve body 68 further forms an annular step 84 so that the downstream side has a smaller diameter.

The inlet pressure thus acts on a surface which is determined by the larger diameter. The seat seal 80 and the downstream side of the discharge valve body 66, however, have a smaller diameter.

In the region of the smaller diameter of the discharge valve body, an annular cavity 86 is formed between the discharge valve body 66 and the inside of the housing 20. In the cavity 86, a sliding seat 88 is guided. The sliding seat 88 has an L-shaped cross section. The sliding seat 88 is movably guided in the axial direction. Furthermore, a sealing ring 90 is provided in the cavity 86. Via a channel, the cavity 86 is hydraulically connected to the medium-pressure chamber.

The mean pressure prevailing in the medium-pressure chamber is also present in the cavity 86. With the drain valve 68 open, as shown in Figure 5, the mean pressure corresponds to the atmospheric pressure. When the drain valve 68 is closed, the medium pressure increases with increasing inlet pressure. The sliding seat 76 then moves to the left in the illustration.

At high inlet pressure with open backflow preventer is the drain valve body 66 against the spring force of the spring 72 in its left stop position. The drain valve is then closed. The backflow preventer 62 is opened. The medium pressure is also in the cavity 86. Due to this medium pressure, the sliding seat 88 is brought with a leg against an annular shoulder in the valve body to stop. However, the pressure in the cavity 86 is also exerted on the rear, protruding part of the pressure surface of the valve body 66. In this way it is ensured that the effective area for the medium pressure is the same as for the inlet pressure. As a result, the forces on the valve body 66 remain independent of the inlet pressure.

In the described arrangement, the valve seat seal 80 has a reduced diameter. Since the forces on the valve body remain unchanged under unchanged pressure conditions, the contact pressure on the seat seal 80 but larger. This increases the sealing force. This allows the realization of a particularly compact system separator with small dimensions.

Behind the downstream backflow preventer 64, a cavity 92 is formed in the housing 20. The cavity 92 communicates via two channels 94 and 96 with the heating circuit. Between the channels 94 and 96, a normally closed, commercially available Magentventil 98 is arranged. Via a control and power supply unit 100, the solenoid valve 98 is driven. If a current flows through the coil of the solenoid valve, it is opened and the water can flow into the heating circuit.

The control and regulating device 100 receives the signal of the arranged in the heating circuit pressure sensor of the heating system. When the pressure falls below a minimum pressure, it opens automatically. The heating circuit is topped up until a preset setpoint is reached. Then the solenoid valve closes again. The controller is also programmed with leakage protection. If the solenoid valve frequently opens and closes again during a selected period of time, i. if the pressure drops too frequently, the solenoid valve is permanently closed and a fault message is issued (cycle monitoring). It is further provided that the solenoid valve opens only for a maximum period of time, otherwise also a fault message is issued (runtime monitoring). This ensures that there will be no refilling if there is a small or large leak in the heating circuit.

The channel 96 opens into the outer space 102 of a ball valve 104. The ball valve 104 is disposed between the inlet 28 and the outlet 26 for the heating circuit. In Fig. 4, the ball valve 104 is opened, i. the passage 108 of the ball 106 is aligned with the inlet 28 and the outlet 26. To fill the heating circuit, the channel 96 communicates via a channel 110 in the ball 106 with the passage 108 in connection. The water can thus flow from the channel 96 through the channel 110 and from there into the heating circuit. For filling or refilling the heating circuit so the check valve 32 and the solenoid valve 98 is opened.

To empty the heating circuit, the ball valve 104 is rotated by means of a tool which acts on the actuating element 112 in a closed position. The passage 110 then aligns with the inlet 28. Then, a drain valve 112 opened and the heating circuit can be emptied through the passage 110 and the drain 30.

FIGS. 1 to 6 show an assembly provided with a system separator of the type CA. For higher risk classes, regulations may also require a type BA system separator. Such a system separator is provided with test ports, which allow a check of the inlet pressure, the pressure in the medium-pressure chamber and the outlet pressure. An example of an arrangement with test connections is shown in FIG. 7 analogously to FIG.

The inlet pressure can be determined via a test port 116 at the opening 22. For measuring the outlet pressure downstream of the non-return valves at a test port 118, which communicates with the cavity 92. For measuring the pressure in the medium-pressure chamber 70, a test connection can be provided directly at the medium-pressure chamber 70. However, this is expensive, because again seals must be used. In the present embodiment, therefore, a preferred, simpler variant was chosen. The test port 120 communicates with the cavity 86 behind the movable sliding seat 88 in connection. Since the cavity is connected via a channel with the medium-pressure space, there is also medium pressure.

Claims (10)

An assembly (10) for supplying water to heating systems with water heater, comprising a fresh water inlet (14) for connection to a water supply port, a first outlet (16) for connecting a water heater and shut-off means (32) for shutting off the fresh water inlet,
marked by (A) a second, provided with shut-off means (98) outlet (26) for connection to the heating circuit of the heating system, and (b) a system separator disposed between the fresh water inlet (14) and the second outlet (26) for physically separating the water supply from the heating circuit by means of two backflow preventers (62, 64) and a differential pressure controlled drain valve (60) disposed between the backflow preventers. An assembly according to claim 1, characterized in that a pressure reducer (38) is provided, via which the water pressure at both outlets (16,26) is adjustable. An assembly according to claim 1 or 2, characterized in that the further shut-off means for shutting off the connection to the heating circuit are formed by a normally closed magnetic valve (98). Assembly according to one of the preceding claims, characterized by control and regulating means (100) for controlling the flow of water into the heating circuit by means of the further shut-off means in response to the signal of a pressure sensor provided in the heating circuit. Assembly according to one of the preceding claims, characterized in that a housing (20) is provided with an elongated shape and so forms a housing longitudinal axis, laterally on the housing of the fresh water inlet (14) and the first outlet (16) are provided Backflow preventer (62,64) are arranged in alignment with the housing longitudinal axis in the housing (20) and are accessible via a nozzle (22) at the end of the housing for maintenance and testing purposes. Assembly according to one of the preceding claims, characterized in that the housing has a heating circuit inlet (28), which together with the second outlet (26) forms part of the heating circuit. An assembly according to claim 6, characterized in that between the heating circuit inlet (28) and the second outlet (26) shut-off means are provided for shutting off the heating circuit. An assembly according to claim 7, characterized in that the shut-off means for shutting off the heating circuit are formed by a ball valve (104) whose ball (106) is in a volume between heating circuit inlet (28) and second outlet (26) Volume on the other shut-off and the system separator with the fresh water inlet (14) is in communication. An assembly according to claim 8, characterized in that a drain valve (30) is provided, via which the heating circuit can be emptied. Assembly according to one of the preceding claims, characterized in that means for monitoring the amount of water supplied to the heating circuit are provided and display means for indicating a fault when the amount of water supplied is outside an allowable range.

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