EP2397777B1 - Housing unit for a heating system - Google Patents

Description

The invention relates to a housing unit for a heater, according to the preamble of claim 1. Such a housing unit is for example from the EP 0 874 201 A2 known.

To the construction of heating systems, in particular provided for wall mounting heaters, d. H. Compact heating systems, such as gas water heaters, to improve and simplify, it is part of the prior art, typically housing units of one or more injection molded plastic parts and incorporate the required electrical, electronic, hydraulic and mechanical components therein. In this case, the housing units for pure space heating systems differ significantly from those for heating systems with two heating circuits, one of which is intended for space heating and one for domestic water heating. The latter have in addition to the always present at least one circulation pump, a heat exchanger, typically a plate heat exchanger and a changeover valve or another circulating pump. In the types that work with switching valve, there are again two variants, namely with reversing valve in the flow or with reversing valve in the return.

A housing unit of the latter type is made, for example EP 0 918 197 B1 known. There, a switching valve is arranged in the suction chamber of the pump, wherein the valve body closes depending on the switching position, the return line of the space heater or the return line from the plate heat exchanger and releases. The valve body is seated in a mounting position about vertically arranged lever whose other end is led out of the housing sealingly down where this is driven by means of an electric servomotor, which is mounted from the outside of the housing.

A disadvantage of the housing unit described therein is that the two line ends, which are closed or released from the valve body, are formed by separate injection molded parts, which must be incorporated into this after the actual housing in this, resulting in additional installation effort and because of the additional Components also means additional tooling. A further disadvantage is that the arrangement of the electric motor on the underside of the housing unit obstructs the natural course of the pipe, in particular because the return pipe for space heating is to be bypassed. Therefore, the housing unit described there has the disadvantage that it has relatively complex lines on the suction side and the plate heat exchanger can only laterally offset behind it can be arranged, which precludes a compact design. Also, a complex and separately produced connection component is to be provided by the channel guide formed within the assembly to the plate heat exchanger, which means further tooling.

Against this background, the invention has the object, a housing unit of a heater for a heating system with two heating circuits and a suction side of the pump arranged switching valve, ie to provide a switching valve in the return lines, which are simple in construction, inexpensive to produce and variable.

This object is achieved according to the invention by the features specified in claim 1. Advantageous embodiments of the invention are specified in the subclaims, the following description and the drawing.

The housing unit of a heater for a heating system with two heating circuits, one for the space heating and one for the domestic water heating forms a pump housing for a circulation pump and comprises a suction side of the pump arranged valve for switching the heating circuits. In the installation position on the back, the housing unit has at least one connection for the direct connection of a plate heat exchanger for hot water heating. Furthermore, the housing unit has on one side an opening for the return of the space heater. The suction chamber formed within the housing unit, to which the suction mouth of the pump connects, has two channels opening into these, of which either one or the other is closed by a valve body of the valve and of which a channel to the line connection for the return of the Space heating and the other channel leads to a connection of the return of the plate heat exchanger.

The housing unit according to the invention can advantageously be connected directly to a plate heat exchanger connected in the installation position with at least one connection. Since the plate heat exchanger in practice is a comparatively solid and made of metal component, this is not only a hydraulic but also a mechanical connection, which also mechanically determines the housing unit within the heater. It can be omitted due to the design with suitable channel arrangement and design to be incorporated in within the housing unit in the suction chamber pipe sections, a production of the housing unit without lost cores is possible. The structure of the housing unit allows a tool which has only drawing and / or pivoting cores, or comparable reversible cores, which is known to be particularly favorable for mass production.

The housing unit advantageously has two connections which are arranged one above the other in the installed position and which are arranged and designed such that they are suitable and intended for direct connection to one of the two connection pairs of the plate heat exchanger. As a result, a rear piping of the housing unit can be completely eliminated, by the two connections immediately adjacent to the plate heat exchanger not only a compact construction but also a good mechanical support of the components involved is ensured.

While the one channel, which opens in the suction chamber of the pump leads to the line connection for the return of the space heater, according to a development of the invention is intended to lead the other channel to the lower port of the terminal pair of the plate heat exchanger. The housing unit according to the invention is versatile, since it can be connected optionally to the right or the left connection pair of the plate heat exchanger. It can therefore be supplied with a housing unit heaters of different design.

It is particularly advantageous if, according to a development of the invention, the housing unit is provided with an opening for the return of the space heating on the underside. This opening, which is advantageously larger than a conventional line connection, can be used to Auskemen part of the inner of the housing unit, wherein for subsequent connection of the return line, a corresponding line connection formed there, for example, by a corresponding metal part or plastic part is incorporated there. In addition, it is particularly advantageous to let the return line open from below into the housing unit, since this is then performed almost directly on the way through the heater. The four water-carrying connecting lines typically come from below in such heaters, in particular wall-mounted heaters.

The channels formed in the housing unit in the suction chamber are advantageously formed by protruding into this pipe sections, which are arranged and aligned so that they end in alignment and at a distance there. Between these ends can then be arranged in a conventional manner arranged at the end of a lever arm valve body, with which either one or the other channel can be closed or released.

It is particularly advantageous if the valve body is arranged at the end of a lever, which is arranged horizontally in the installation position and laterally, preferably left side sealing out through a housing wall to the outside, the other end coupled with a there attaches to the housing unit from the outside servomotor is. Such a laterally mounted servomotor is easily accessible and therefore in operation, that is in the installed position, interchangeable with a few simple steps.

To deposit the entrained in the primary circuit gases, which are usually introduced by the heating circuit of the space heating but also otherwise, it is advantageous if the housing unit is formed so that the suction chamber an air separation housing connects, which is part of the housing unit. Such an air separation housing can thus typically be formed integrally with the structural unit and is located in the region in front of the suction mouth, ie where the flow is calmed the most and therefore a gas separation is most effective.

Heaters of the type in question typically have a closed by a pressure relief valve bypass between the heating flow and return heater to ensure that even when closed in space heating all thermostatic valves are, the circulation function is ensured within the heater and thus a heat dissipation from the primary heat exchanger. According to the invention, the housing unit is designed so that the bypass opens into the suction chamber of the pump, wherein the pressure relief valve is incorporated into the housing unit suction chamber side. Characterized in that the pressure relief valve is incorporated into the housing unit suction chamber side, with a suitable design of the housing unit casings for the bypass can be largely eliminated, it is sufficient a corresponding line connection for the bypass to the housing unit.

In order to save the usual bypass line within the heater, is provided according to the invention that the bypass extends at least partially through the heat exchanger supplying the plate heat exchanger, the channel in the housing unit, which leads back to the one port of the plate heat exchanger , also part of the bypass. This solution according to the invention, in which ultimately a separate bypass line can be almost completely dispensed with, is based on the consideration that the line leading through the plate heat exchanger forms a parallel line to the lines leading to the radiators for space heating of the heater anyway Circuit can also serve as a bypass line.

In this case, the housing unit according to the invention according to a development of the invention, a channel that leads from the plate heat exchanger to the valve for switching the heating circuits, which has a branch for the bypass, by the pressure relief valve in the normal Operation is closed and opens in the suction chamber. This diversion is required so that even when closed by the valve return line of the heat exchanger, the bypass function is ensured.

Advantageously, in the case of the housing unit according to the invention, the bypass is formed by a bypass duct which opens outwardly at the top in the housing unit and which cuts the channel leading from the heat exchanger to the valve for switching over the heating circuits and is conductively connected to the suction space by a wall recess. This embodiment is structurally particularly favorable, since such outwardly opening channels can be produced in tool injection molded plastic parts without lost cores. In addition, the arrangement has the advantage of short lines. The bypass is thus almost realized by the shortest route, at the same time the housing unit serves to receive the pressure relief valve, which closes the bypass at normal pressure conditions.

The arranged in the bypass pressure relief valve is advantageously used in the manner of a cartridge from the outside into the bypass channel and releasably secured there. In this way, the pressure relief valve can be checked for maintenance purposes and optionally replaced quickly, without the need for disassembly of lines or line connections.

As already explained above, it is particularly advantageous if the return of the plate heat exchanger is formed by the lower port, which is connected via the other channel with the suction chamber and the valve disposed therein within the housing unit. Then, namely, the upper terminal of this connection pair can be formed by a preferably bent by about 90 ° and in the installed position preferably to the left directed duct, the Part of the housing unit is, however, is arranged with respect to the suction chamber outside the housing unit. Such a duct is low tooling feasible and also leads the upper line connection of the plate heat exchanger in an easily accessible area of the heater, where the line connection with the service water pipe can be made.

Preferably, the housing unit is formed by a one-piece injection molded plastic component which is produced without lost cores. It is understood that the cover disc to be incorporated between the pump impeller and the suction chamber, which forms the later suction mouth of the pump, and for example the conduit connection for the return of the space heater, which is incorporated into the lower-side opening of the housing unit, as separate components made of plastic and / or metal are made, this one-piece in the sense of the invention does not oppose.

Fig. 1

in stark vereinfachter schematischer Einstellung ein hydraulisches Schaltbild einer Heizungsanlage,

Fig. 2

in vereinfachter perspektivischer Explosionsdarstellung eine Gehäuseeinheit nach der Erfindung mit An- und Einbauteilen in Einbaulage gesehen schräg von links und vorne,

Fig. 3

eine perspektivische Explosionsdarstellung gemäß Fig. 2, jedoch in Einbaulage gesehen schräg von rechts und vorne,

Fig. 4

eine perspektivische Explosionsdarstellung gemäß Fig. 2, jedoch in Einbaulage gesehen schräg von rechts und hinten,

Fig. 5

eine perspektivische Explosionsdarstellung die Gehäuseeinheit ohne Wärmetauscher von vorne, rechts und oben gesehen,

Fig. 6

eine perspektivische Explosionsdarstellung gemäß Fig. 5 schräg von links hinten gesehen,

Fig. 7

eine Explosionsdarstellung gemäß Fig. 2 von oben gesehen,

Fig. 8

einen Schnitt durch die Gehäuseeinheit in einer Ebene etwa parallel zum Plattenwärmetauscher und

Fig. 9

eine perspektivische Explosionsdarstellung entsprechend Fig. 2 einer Ausführungsvariante.

The invention is explained in more detail with reference to an embodiment shown in the drawing. Show it:

Fig. 1

in a highly simplified schematic setting a hydraulic circuit diagram of a heating system,

Fig. 2

in a simplified perspective exploded view of a housing unit according to the invention with attachments and built-in parts seen in installation position obliquely from the left and front,

Fig. 3

an exploded perspective view according to Fig. 2 , but seen in installation position obliquely from right and front,

Fig. 4

an exploded perspective view according to Fig. 2 , but seen in installation position obliquely from the right and rear,

Fig. 5

an exploded perspective view of the housing unit without heat exchanger seen from the front, right and up,

Fig. 6

an exploded perspective view according to Fig. 5 seen obliquely from the left behind,

Fig. 7

an exploded view according to Fig. 2 seen from above,

Fig. 8

a section through the housing unit in a plane approximately parallel to the plate heat exchanger and

Fig. 9

an exploded perspective view accordingly Fig. 2 an embodiment variant.

The basis of Fig. 1 shown heating system has two heating circuits, one for space heating and one for domestic water heating. The system consists of the actual heater, which can be designed as a wall-mounted gas heater or as a floor standing heater. The device side part is in Fig. 1 formed by the part of the heating system shown above the broken line 0, the rest of the building-side part through the underlying.

The heater has in four at the bottom of the device exiting water line connections, namely a heating flow connection 1, a heating return connection 2, a cold water connection 3 and a hot water connection 4. The other connections (gas, electric) are not shown. This heater thus serves on the one hand to supply heat exchangers 5, for example in the form of radiators, for space heating and for heating domestic water. This is inside the heater, a plate heat exchanger 6 is provided, via which the coming of the cold water connection 3 cold service water is heated and directed to the hot water connection 4. The heating takes place by the hot water generated in the heater in a primary heat exchanger 7, for example by combustion of gas, which is guided in the counterflow through the plate heat exchanger 6.

For circulating the heat transfer medium, typically water, through the primary heat exchanger 7 and the secondary heat exchangers 5 and 6, a circulating pump 8 is provided in the form of a wet-running centrifugal pump. This circulation pump 8 conveys the heat transfer medium via a pressure line 9 to the primary exchanger 7, where this is heated and fed either via a line 10 to the plate heat exchanger 6 or via a line 11 to the heating flow connection 1 and from there the heat exchangers 5 of the space heater. The emerging from the heat exchangers 5 and 6 medium is fed via a return line 12, which leads the water coming from the heat exchanger 5, and via a return line 13, which leads the water coming from the heat exchanger 6, a changeover valve 14, which depending on the switching position either Return line 12 or the return line 13 to the suction side of the pump 8 connects.

The switching valve 14 is controlled by means of an electric motor such that in operation, the return line 12 is connected to the pump 8. If warm water is to be taken off at the hot water tapping point, this is detected by means of a flow sensor 16 and the valve 14 is actuated in a switching manner by means of the electric motor so that the return line 13 is connected to the suction side of the pump 8.

In addition, the heater on a bypass line 17, which ensures that even when closing both heating circuits circulation within the heater is possible. For this purpose, a pressure relief valve 18 incorporated in the bypass line, which opens from a preset differential pressure. In addition, the heater to other components, of which only an example here a compensating vessel 19, a safety valve 20 and a filling valve 21 are shown.

In order to facilitate the construction of the heater, in particular the internal structure and the piping within the device both during assembly and during subsequent maintenance, a housing unit 22 is provided, which is formed as a one-piece plastic injection molded part.

In the execution of the FIGS. 2 to 8 the housing unit 22 also includes the in Fig. 1 22a, namely a pipe bend 41 for internal piping of the appliance-side cold water connection with the cold water connection of the housing unit 22. The housing unit 22 also has the rear upper connection 42 for the plate heat exchanger 6 and the flow meter 16.

This housing unit 22 forms at its front in the installed position a pump housing 23 and the associated flange for a pump head 24 in a conventional manner consisting of electric motor, terminal box with optionally built-in electronics and sitting at the free end of the motor shaft impeller. This pump head 24 is attached to the front end of the housing unit 22 by incorporating an annular cover disk 25 in such a way that the rotary impeller is arranged in the region of the pump housing 23. The central recess of the cover plate 25 forms the suction mouth 26 of the pump.

At the top of the pump housing 23 forming part of the housing unit 22 includes a discharge nozzle 27 with a corresponding line connection. The suction mouth 26 opens into a within the Housing unit 22 centrally formed suction chamber 28, which also forms a housing for the switching valve 14. The suction chamber 28 has a substantially cylindrical shape and has an opening 29 in its mounting position on the underside, which is provided for Engliedern a connection part 30, which serves to connect a leading to the heater return connection return line 12. This connection part 30, which preferably consists of metal, is sealingly incorporated into the opening 29 by means of an O-ring and fixed in a form-fitting manner by means of a U-shaped bracket.

In this case, the upper end 31 of the connecting part 30 simultaneously forms a valve seat within the suction chamber 28. This valve seat is, for example, in Fig. 6 shown within the suction chamber. The associated valve body 32 is formed by a substantially cylindrical flat body which sits at the end of a lever 33 which is sealingly passed through an opening on the left side of the housing unit through the wall of the suction chamber 28, and the other end 34 of a mounted on the outside of the housing unit mounted electric motor drive unit 35. The lever 33 is pivotally held in a bearing 36 and sealed with respect to this, which incorporated in the stepped and end towards the flange-shaped opening 37 of the housing unit 22 and fixed by the subsequently incorporated motor bracket 38.

The open end 31, so the valve seat with distance opposite the open end of a molded in the suction chamber 28 elbow 39 which forms with its free into the suction chamber 28 projecting end a valve seat 31 opposite valve seat, which is alternatively closed by the valve body 32. This pipe bend 39, which is formed integrally with the housing unit 22, opens into the lower rear-side connection 40 in the installation position, with which the housing unit is connected to the lower right-hand connection in the installed position the plate heat exchanger 6 is connected. This pipe bend 30, since it is accessible both from the rear in the installation position to the rear opening and through the lower opening 29 in the housing unit and the pump side from the front, in the production with a Tool to be manufactured with drawing heads and without lost cores.

Furthermore, the housing unit has an outside of the suction chamber 28, that is on the outside of the housing unit 22, integrally formed pipe bend 41, which forms the upper connection 42 for the heat exchanger and which is designed to connect the cold water supply 3 leading cold water line. A corresponding line connection 43 is, for example, in Fig. 6 visible, noticeable. This pipe bend 41 may also be formed as a separate component independently of the housing unit. Even with one-piece design with the housing unit of this elbow 41 may be made of other material, which is materially adapted to the temperature level and composition of the flowing medium.

Further incorporated into the suction chamber 28 and this cutting is a Luftabscheidegehäuse 44, in which a breather valve 45 is inserted bayonet-like. The Luftabscheidegehäuse 44, which extends substantially as far as the actual, the suction chamber 28 forming housing upwardly this is cylindrical and seen from above right next to the pipe bend 41 to the rear wall of the suction chamber 28 subsequently formed in the housing unit (see Fig. 4 ). Under the Luftabscheidegehäuse 44, a rear port 46 is provided, which opens into the suction chamber 28. Furthermore, two ports 47 and 48 opening laterally into the suction chamber 28 are provided on the right side in the installed position. About these ports 46 to 48, for example, the expansion tank 19 sensors or others suitable hydraulic connections are connected, which are to be hydraulically connected to the suction chamber 28.

Furthermore, the back of the suction chamber 28 is followed by a channel 49 directed downwards by 90 °, which is arranged at the bottom of the suction chamber 28 and is closed off by a sealing plug 50. After removal of the sealing plug 50, the housing unit can be almost completely emptied via this channel.

Seen from above, approximately in the region between the pipe bend 41, the air separation housing 44 and the discharge nozzle 27, an obliquely directed towards the inside of the suction chamber 28 channel 51 is provided, which forms the bypass line 17. This channel 51, which is open to the outside, opens into the suction chamber 28 and cuts the line 13 within the housing unit 22, wherein the free end of this channel 51 is provided with a bayonet, so that a cartridge 52 in the free end of the channel 51 can be inserted and There is lockable. This cartridge 52 comprises a pressure limiting valve 18, namely the valve 18, and is arranged in the installed position so that the valve 18 is arranged between the conduit 13 and the suction chamber 28 of the pump. The channel 51 thus forms on the one hand the end of Rücktaufleitung 13, where it is designed as a valve seat end to be closed or opened by the valve body 32, on the other hand, this channel 51 also forms part of the bypass line 17, which Fig. 1 illustrated by the line 10, the heat exchanger 6 and the return line 13 is formed. The channel 51, however, has a recess 53 in the wall to the suction chamber 28, approximately where the pressure relief valve 18 is incorporated in a cartridge-like manner. This recess 53 forms the actual bypass, namely the connection to the suction chamber 28 when the pressure-limiting valve 18 is open. This connection in conjunction with the pressure-limiting valve 18 thus ensures that the X channel 51 is closed at the end by the valve body 32 , a line connection is made to the suction chamber 28. Since the pressure relief valve 18 is accessible in the installed position from the outside through the free end of the channel 51. can be adjusted via this access in the installed state of the limiting pressure on the valve 18, provided that it is an adjustable valve.

As in Fig. 1 shown schematically, the housing unit 22 is not mandatory as in the embodiment according to the Fig. 2 to 8 also include part 22a. In the embodiment, as in Fig. 9 is shown, this part 22a of the housing unit 22 is formed as a separate injection-molded component, wherein in this component 22a in a connection opening from above the flow meter 16 is incorporated like a cartridge.

The housing unit described above is connected to the right terminal pair of the plate heat exchanger 6. However, it can also be connected to the left connection pair. It is understood that then the connection of the plate heat exchanger must also be done in the reverse manner.

LIST OF REFERENCE NUMBERS

0

- horizontal line in Fig. 1

1

- Heating flow connection

2

- Heating return connection

3

- Cold water connection

4

- Hot water connection

5

- Heat exchanger space heating

6

- Plate heat exchanger

7

- primary heat exchanger

8th

- Circulation pump

9

- pressure line

10

- Management

11

- Management

12

- Return line space heating

13

- Return line for domestic water heating

14

- Changeover valve

15

- electric motor

16

- Flow meter

17

- bypass line

18

- Pressure relief valve

19

- Expansion tank, expansion vessel

20

- safety valve

21

- filling valve

22

- Housing unit

22a

- separate component ( Fig. 9 )

23

- Pump housing

24

- Pump head

25

- cover letter

26

- Suction mouth

27

- discharge nozzle

28

- suction chamber

29

- opening

30

- Connector

31

- upper end of 30

32

- valve body

33

- Leverage

34

- free end of 33

35

- Drive unit

36

- Camp

37

- opening

38

- Motor bracket

39

- pipe bend

40

- lower connection for heat exchanger

41

- pipe bend

42

- Upper connection for heat exchanger

43

- Line connection of 41

44

- Air separation housing

45

- Breather valve

46

- Connection

47

- Connection

48

- Connection

49

- Connection

50

- sealing plug

51

- Channel

52

- cartridge with pressure relief valve 18

53

- recess

Claims (12)

1. A housing unit for a heating apparatus with two heating circuits, one for room heating and one for service water heating, and which forms a pump casing (23) for a circulation pump (8) and which at the suction side of the pump (8) comprises a valve (14) for switching over the heating circuits, with which in the installed condition, at least one connection (40) for the direct connection of a plate heat exchanger (6) for service water heating is provided at the rear side of the housing unit (22), with which an opening (29) for the return of the room heating is arranged at one side, in which opening a suction chamber (28) is formed, to which suction chamber the suction port (26) of the pump (8) connects and runs out into the two channels, of which selectively the one or the other can be closed by a valve body (32) of the valve (14) and of which the one channel leads to the conduit connection (2) for the return and the other channel to the connection (40) of the plate heat exchanger (6), characterised in that a bypass (17) which is closed by a pressure-limiting valve (18) and which runs out in the suction chamber (28) of the pump (8) is provided between the heating feed and the heating return, that the pressure-limiting valve (18) is integrated into the housing unit on the suction chamber side, that the bypass (17) at least in sections runs through a conduit (10, 13) which supplies the plate heat exchanger (6) with heat, and that the other channel which at the rear side leads to the one connection (40) of the plate heat exchanger (6) also forms part of the bypass (17).
2. The housing unit according to claim 1, characterised in that two ports (40, 42) arranged one over the other in the rear installation position are provided for direct connection to one of the two port pairs of the plate heat exchanger (6).
3. The housing unit according to claim 2, characterised in that the other channel leads to the lower port (40) of the port pair (40, 42) of the plate heat exchanger (6).
4. The housing unit according to one of the preceding claims, characterised in that the opening (29) for the return line of the space heater is formed by a line port (2) on the bottom side of the housing unit (22).
5. The housing unit according to one of the preceding claims, characterised in that the channels are formed by pipe sections (31, 39) extending into the inlet chamber (28), which end there in an aligned manner, spaced apart from each other.
6. The housing unit according to one of the preceding claims, characterised in that the valve body (32) is arranged at the end of a lever (33), which in the installation position is horizontally situated, and tightly guided outwardly through a housing wall on the side, preferably on the left side, while its other end (34) is coupled with a positioning motor (35) that can there be secured to the housing unit (22) from outside.
7. The housing unit according to one of the preceding claims, characterised in that the inlet chamber (28) adjoins an air separation housing (44), which is part of the housing unit (22).
8. The housing unit according to one of the preceding claims, characterised in that the channel (13) leading from the plate heat exchanger (6) to the valve (14) for switching the heating circuits exhibits a branch for the bypass (17) that is closed by the pressure-relief valve (18) and empties into the inlet chamber (28).
9. The housing unit according to one of the preceding claims, characterised in that the bypass (17) is formed by a bypass channel (51) that preferably empties to the outside above in the housing unit (22), preferably intersects the channel (13) leading from the plate heat exchanger (6) to the valve (14) for switching the heating circuits, and is connected by a line through the wall recess with the inlet chamber (28).
10. The housing unit according to claim 9, characterised in that the pressure-relief valve (18) is inserted like a cartridge (52) into the bypass channel (51) from outside and detachably secured.
11. The housing unit according to one of the preceding claims, characterised in that the port (42) of the housing unit (22) leading to the upper port of the port pair of the plate heat exchanger (6) forms the end of a line channel (39) preferably bent by about 90° in the installation position, preferably toward the left side, the other end of which is formed on the outside of the housing unit, also as a port (43).
12. The housing unit according to one of the preceding claims, which is fabricated as a one-piece injection molded plastic.

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