DE2319559A1 - HEAT EXCHANGER DEVICE - Google Patents

Description

Heat exchanger device The invention tXsw relates to a heat exchanger device, In particular for the heating of raw water in connection with collective heating systems, with one connected to the domestic water network via a cold water inlet and that expected process water absorbing hollow body in a surrounding it Container is arranged, which when used water withdrawal via a hot water drain heating water with almost boiler water temperature by means of an automatic domestic hot water priority system is fed.

When heating hot water, it is essential that this is done as soon as possible or shortly after the start of the tapping process, hot water of sufficient temperature and Sufficient quantity is available. On the other hand, however, should be during the removal breaks not Too much domestic water can be stored, as sufficient at all times a lot of freshly heated and not stale service water is available target. For the reasons mentioned, once-through heat exchangers are often used, where one or more pipe coils through which the service water flows at good Heat transfer are arranged in a heating water reservoir. It is also known such a heat exchanger parallel to the Helzkreislauf of a collective heating system to switch and to supply heating water to it via a pump when domestic water is withdrawn takes place and if the hot water temperature falls below a certain during the withdrawal breaks Minimum threshold drops. The first-mentioned control takes place by means of a pressure-dependent one or thermostatic Bruuchwasser priority automatic, which on the domestic water withdrawal and the external heating circuit is interrupted, so that while the domestic water is being drawn off the entire boiler water for domestic water heating is available. As the heat exchanger in this case, heating water with approximately boiler water temperature flows through it rapid heating takes place when the service water flows through, so that the heat exchanger only a comparatively small volume of service water, even if there is a greater demand for hot water must have. The second control for maintaining a heat supply in the removal breaks happens in such a way that from the outer helicopter water circuit Part of the heating water is thermostatically controlled and branched off for domestic water heating will.

The heat exchanger device described has the essential The advantage is that an effective and fast water supply is available when the water supply is low Heating is possible because the heat exchanger is used for heating water when hot water is drawn off r with approximately the boiler water temperature is supplied. However, it is known that at a temperature of the domestic water above a certain Limit temperature, which can be between 50 and 700 C, mineral substances are excreted which, when deposited, cause wall encrustations and pipe constrictions, what with a deterioration in the heat transfer and possibly with a failure of the heat exchanger is connected. This makes scale formation very dreaded it required that the known heat exchangers from time to time and at very hard water can quite often be subjected to a complex cleaning process have to. For reasons of toast, one has often already gone over to it instead of the expensive cleaning to provide for an exchange of the damaged parts.

It is not critical if the domestic water when the Exceeds the limit temperature as the minerals do not settle in this state can. Under no circumstances, however, may the domestic water be used during the withdrawal breaks, i.e. in Standstill, exceeding the limit temperature, otherwise calcification will always occur occurs, including in the downstream pipe network. Such a disadvantageous one Exceeding the Grenztenperatur is b the known heat exchanger devices not to be avoided with continuous operation, especially after the dispensing process has been terminated, so that a calcification Depending on the type of water and the heat exchanger more or occurs less quickly and strongly.

There are also known heat exchangers in which a heating water coil is arranged in a larger service water reservoir. Since this is a large supply of process water is available that can be heated for longer periods of time, it is not absolutely necessary that the lleizwasser in the pipe coil approximate Has boiler water temperature. However, if such a stock water heater in accordance with the aforementioned run-through water prepares switched and is controlled, it can be operated safely with boiler water temperature, as overheating of the domestic water is not possible in this case. Such In many cases, however, consumer water heaters are undesirable and numerous Disadvantages on. On the one hand, there is always a large and stale water supply Spetchert, and on the other hand it is necessary to use the entire external water tank and the outer surface of the Helzwasser pipe loop made of one for service water to produce suitable and / or machined material so that all hygienic Requirements can be met. Dlese measures are very expensive and can be avoided with a continuous service water consultant, since only that The interior of the domestic water pipe is made of a suitable material for a long time and like all parts through which water flows from time to time for reasons of hygiene needs to be cleaned.

The object of the invention is thus to create a heat exchanger device of the type mentioned with a continuous service water heater or with an internal one Domestic hot water body and an outer heating water tank, with In all Operating conditions a calcification is safely avoided and a cleaning of the from Process water flows through parts in the simplest way, without installation effort and without danger is possible. The new heat exchanger device should be robust and simple to build and have a long service life.

The solution to the problem is given by a heat exchanger device, especially for domestic water heating in connection with collective heating systems, with one connected to the domestic water network via a quay water inlet and that to be heated domestic water receiving hollow body, which is in one surrounding it is arranged container, which when used water withdrawal via a Hot water drain by means of an automatic service water priority system, heating water with approximately Boiler water temperature is supplied, achieved by such a ratio of the Process water volume of the hollow body to the heating water volume of the container in which in the case of a pause for domestic hot water, the mixed temperature of the initially cold one Service water and hot heating water are always below the limit temperature for scale formation and by an interrupted Helzwasser inlet to the tank for desludging cold water flushing that can be switched on in the hollow body, with the Kait water flowing through it the hollow body is passed into a drain. According to one embodiment, there is the hollow body consists of one or more serpentine or parallel-connected coils Pipe coils. In a particularly advantageous embodiment, the coil or Rohrschlanqen led around an inner container and with this in terms of flow technology Connected in series, with a cold water inlet to the inner tank and a hot water outlet are connected to the coil end. In a further embodiment, the inner container have a round cross-section and an approximately vertical longitudinal axis, with the lower bottom slightly curved outwards and with the longitudinal dimension of the inner container corresponds approximately to the longitudinal dimension of the container. Furthermore is It is possible that the inner container is in normal operation in its central bottom area having connected to the cold water inlet connection and in its upper area is connected to the pipe coil or coils. It proves to be particularly advantageous if the cold water rinse is designed as a backwash, by the end of the pipe coil Cold water is supplied after flowing through the pipe coil or pipe coils and the inner container flows into a drain via its lower connection. Included can change direction from normal to rinsing operation by means of two each in the inlets and outlets of the hollow body lying valves are carried out.

The main advantage of the new heat exchanger device for Domestic water heating consists in that with a relatively small domestic water supply Hot water is always available quickly and sufficiently to prevent calcification respectively.

Scale formation is completely avoided and that in the simplest possible way cleaning or desludging of the parts through which the process water flows without Assembly is possible. The points mentioned are essential what also applies to the Spnlbefetrieb, since it has been shown that also with service water below the limit temperature exude small amounts of substances, but they are always loose stay and have nothing to do with calcification or scale formation.

These substances settle on the wall and make you light removable sludge, which increases the level of efficiency and makes it hygienic Grounds should be removed from time to time. This is done in such a way that the parts through which the service water flows, possibly in countercurrent, of cold water be flushed through. This Sp-Ulwasser enriched with sludge is drained geleltet, whose bacterial balance is not disturbed due to the use of cold rinsing water will. Since the new heat exchanger device is completely safe from calcification, they can be run safely without a complex water softener. The heat exchanger itself can be very small and, for example, with a compared to the diameter short in height, so that its outer torm resembles a discus disc Due to the small footprint, it is extremely good for storage below the insulation a boiler.

The invention is illustrated below with the aid of a drawing Embodiment explained in more detail.

A heat exchanger device 10 comprises various parts from those of the through-use water advisors within the insulation of a Helzkessel and the connection and control system are arranged outside the boiler.

The continuous domestic water heater consists of one of the domestic water flowed through hollow body 12 and a surrounding this flowed through by the heating water Container 14. It is particularly economical to fluidically consist of the hollow body 12 from at least two to build parts connected in series, one of which is used as an inner container 16 has a flat and approximately cylindrical shape, around the longitudinal selnes mantels one or more tn rows or coils 14 connected in parallel are laid around are.

At the end of the pipe coil or pipe coils 14 is with the Innenbehaiter 16 in its upper area over a belsplelsweise approximately tangential mouth tied together. The lower bottom 22 of the inner container 16 is slightly bulged outwards and has in its central area a connection 24, above which the continuous use water advisor cold hot water is supplied when hot water is withdrawn. This rises in the inner container 16 and enters the pipe coil or pipe coils in the upper area 14. Behind a pipe coil end 20, hot water can be used at a hot water outlet 18 can be removed.

The container 14 through which the heating water flows is via a heating water inlet 36, in the course of which there is a pump and / or gravity brake 38, and one Heating water defrost 40 Via boiler connections 42 and 44 with a heating water jacket connected to a boiler. The pump and / or gravity brake 38 can be in the Withdrawal pauses, thermostatically controlled, switched on and while the hot water is being withdrawn yon an automatic domestic water priority system, not shown, preferably pressure-dependent Kind of controlled.

In normal operation, the cold domestic water flows from the cold water inlet 10 passes through a valve 32 and the connection 24 into the inner container 16. From there it via the pipe coil or pipe coils 14 via a further valve 28 to the hot water drain 18. Because of the high heating water temperature of around 80 to 90 ° C, one is relative short pipe coil section for heating up the water supply is sufficient, see above that a low design of the inner container 16 and thus also of the container 14 is possible. On the other hand, however, a Mixed temperature of the process water in the inner container 16 and in the pipe coil or coils 14 above the limit temperature for scale formation is safely avoided. It deals is therefore a real continuous consumer water heater, because the volume of the inner container 16 cannot hold a sufficient supply of process water by far, the inner container 16 essentially means that the mixed water temperature after completion of the Dispensing process by reheating the heating water in the container 14 within the permissible limits remains.

Even when operating a heat exchanger with domestic water below the limit temperature it has been shown that a loose, sludge-like deposit substances contained in industrial water cannot be avoided. To achieve a completely reliable, durable and effective heat exchanger device with the simplest operability and maintenance is therefore a backwash operation provided that from time to time a removal of the muddy paragraph with Performs cold water. The washing water is preferably carried out in the backwash mode wherein the valves 28 in the hot water outlet 18 and cold water inlet 10 are blocked.

Then one opens in a connecting line between the coil end 20 and the Kaitwasser inlet 10 lying valve 30 and one Valve 34, which has a drain 26 to the connection line between the connection 24 and the valve 32 is coupled. In the backwash mode, the coiled pipes are thus or coils 14 of cold water flows through in the opposite direction, so that this in the upper region of the inner container 16, in particular at an approximately tangential inlet mouth flows through the inner container 16 or its walls in a circling manner and in the deepest Central area of the base 22 over the connection 24 and the opened valve 34 in the drain 26 flows off. Since backwashing is done with cold water, the drainage pipes are not disrupted.

The continuous flow water heater can, as the following information can be seen to be very small. For example, if heating water with 80 ° C and cold water with 10 ° C is used with a heating water volume of 6 1 and a service water volume of 5.8 1, of which about 1 1 on the pipe socket It is assumed that the limit temperature is safely avoided. If it is assumed that the service water that has flowed into the inner container 16 is still roughly the same as the cold water temperature and the mean temperature of the in the coils 14 partially heated water is 40 ° C, results after the completion of the tapping process in the entire continuous consumer water heater a mixing temperature of about 48-0 C. Bel only 5.8 1 hot water volume it is therefore effective to avoid calcification of the continuous consumer water heater.

This process water volume can be reduced with a corresponding reduction in the Heating water and / or coil volume can be further reduced. The temperature can also be controlled via the flow rate. You can change the boiler output approximately correspond.

The new heat exchanger device is extremely simple and robust and inexpensive to set up. Due to the continuous operation, it can only take up very little space Sufficient hot domestic water can always be withdrawn, and in spite of the operation Heating water that is close to the boiler temperature will shorten the service life and the formation of scale, which would reduce efficiency, is safely avoided. The cleaning of the The hollow body through which the process water flows is in a simple manner by means of a backwash operation with cold water that does not have any harmful effects on the bacterial operation of the drainage channel exercises, possible As with all continuous flow water heaters with internal Service water hollow body only has to have a correspondingly hygienic surface on the inside have, while its outer surface, which is surrounded by the heating water, as well as the inner surface of the container do not have to meet these conditions. The small size that largely maintenance-free or the simple backwashing operation and the long service life open up an extremely wide range of applications for the new heat exchanger device.

Expectations:

Claims (7)

Claims t9 heat exchanger device, in particular for Brauchwaisererwärmung in connection with collecting systems, with a cold water inlet on the Connected domestic water network and receiving the domestic water to be heated Hollow body, which is arranged in a container surrounding it, which is used when tap water via a hot water drain using an automatic hot water priority system for heating water is supplied at approximately the boiler water temperature, g e k e n n z e 1 c h n e t d u r c h such a ratio of the service water volume of the hollow body (12) to the heating water volume of the tank (14), at which in the case of a pause for domestic water withdrawal the mixture temperature of the initially cold service water and hot heating water is below the limit temperature for scale formation, and by eirv with interrupted Heating water supply to the container (14) for desludging the hollow body (12) can be switched on Cold water rinsing, in which cold water after flowing through the hollow body (12) in a drain (26) is passed. 2. Heat exchanger device according to claim t, d a -d u r c h it is not indicated that the hollow body consists of one or more in series or coiled pipe coils (14) connected in parallel. 3. Heat exchanger device according to claim 2, d a -d u r c h G e k e n n nz e 1 c h n e t that the pipe coil or pipe coils (14) around a Inner container (16) out and with this fluidic in Are connected in series, with a cold water inlet (10) with the inner container (16) and a hot water drain (18) are connected to the pipe loop end (20). 4. Heat exchanger device according to claim 3, d a -d u r c h g It is noted that the inner container (16) has a round cross-section and has an approximately vertically extending longitudinal axis, wherein the lower base (22) is slightly curved on the outside and where the longitudinal dimension of the inner container (16) corresponds approximately to the longitudinal dimension of the container (14). 5. Heat exchanger device according to one or more of the preceding Claims that the inner container (16) In its middle floor area one in normal operation with the cold water inlet (10) has connected terminal (24) and in its upper region with the or connected to the coils. 6. Heat exchanger device according to one or more of the preceding Claims, that the Kaitwasserspülung is designed as a backwash by supplying cold water to the coil end (20) after flowing through the pipe coil or pipe coils (14) and the inner container (16) flows through its lower connection (24) into a drain (26). 7. Heat exchanger device according to claim 6, d a -d u r c h g It is not noted that the changeover from normal to rinsing operation by means of Two valves (28, 30; 32, 34) is carried out.