DE202009018196U1 - Highly efficient, solar-assisted condensing gas storage heater for liquid or gaseous fuels for generating domestic hot water and heating heat for space heating - Google Patents

Abstract

Highly efficient, solar-assisted condensing storage heater for liquid or gaseous fuels for the generation of domestic hot water and heating for space heating, characterized in that in a cylindrical, standing water storage tank, which • has a warm zone in the upper part, which stores sufficient heat for at least one domestic hot water tap , and from the lower area of which heating heat can be extracted for room heating, which is mixed by means of a mixer to the required flow temperature, • has a combustion chamber in the middle part, which limits the warm zone downwards and this according to the required target temperatures for domestic hot water and room heating Natural circulation warmed. The burner, which is operated with the lowest possible burner output and therefore long burner runtimes, is located in the combustion chamber. • The lower part has a cold zone, in particular generated by cold drinking water flowing in during domestic hot water tapping, in which an exhaust gas heat exchanger and a solar heat exchanger are arranged, the heating gases after leaving the combustion chamber led downwards in the exhaust gas heat exchanger arranged in the cold zone and ...

Description

Technical area

The invention described here belongs to the field of storage heat generating devices for obtaining heat for domestic hot water production and space heating, fired with liquid or gaseous fuels using the latent heat in the heating gas (condensing technology), supported by the use of solar energy.

State of the art and shortcomings of previously known designs

Solar-assisted heat generation systems for liquid or gaseous fuels, which serve domestic hot water production and space heating in residential buildings, usually consist of a boiler, which first heats heating water, and a separate domestic hot water tank, which is heated by the heating water. Furthermore, additional storage zones for domestic hot water production and Heizwasserpufferung are required for the thermal solar system, creating additional space and significantly higher costs. The low temperatures of the incoming cold water (around 10 ° C) during domestic hot water tapping are indeed used for efficient operation of the solar system, but not for more efficient operation of the boiler by cooling the hot gases. Space-saving boilers with low water contents are also for safety reasons (ensuring a minimum volume flow) afflicted with the disadvantage of a maximum temperature spread, the resulting minimum return temperature is well above that of the inflowing cold water. Even condensing boilers have these limitations and thus leave a considerable potential for increasing efficiency unexploited.

Furthermore, state-of-the-art devices aim to operate domestic hot water only for a short time (about 15-45 minutes), after which they will be available again for heating. This leads to significantly higher rated power of the heater than required for space heating, as well as to relatively small memory sizes. Furthermore, there is the disadvantage that the modulation range of the burner power is not or only partially available for adaptation to lower heat outputs available.

Another disadvantage of such compact, equipped with small heat exchange surfaces condensing boilers for space heating is the high water-side pressure loss to achieve a turbulent flow for better heat transfer, which in turn requires high hydraulic power (and thus high electrical pump power).

With increasingly improved thermal insulation standards of residential buildings, the proportion of domestic hot water production compared to the proportion of space heating always increases, so that the overall efficiency of the appliances is increasingly affected by the low efficiency of domestic hot water production.

• • Bevorratung von Wärme in Form eines erwärmten Speichermediums anstelle erhöhter Brennerleistungen zur Deckung von Bedarfsspitzen,
• • Integration des Feuerraums mit Brenner in das Gerät,
• • Schaffung einer Kaltzone zur Auskühlung der Heizgase unter die Rücklauftemperatur des Heizmediums (verbesserter Brennwertbetrieb),
• • Integration einer thermischen Solaranlage, die ebenfalls auf die Kaltzone arbeitet,
• • Bereitstellung sowohl von Trinkwarmwasser als auch Wärme zur Raumheizung.

So far, there are only a few approaches to remedy these shortcomings by combining the following measures in a single device:

• • storage of heat in the form of a heated storage medium instead of increased burner capacity to cover demand peaks,
• • integration of the combustion chamber with burner in the device,
• Creation of a cold zone for cooling the hot gases below the return temperature of the heating medium (improved condensing operation),
• • Integration of a thermal solar system, which also works on the cold zone,
• • Provision of both domestic hot water and heat for space heating.

• • Die Abwärtsführung der Heizgase im Speichermedium erfolgt nicht in einem großflächigen Wärmetauscher,
• • Eine konsequente Unterscheidung zwischen oberer Warmzone und unterer Kaltzone des Wasserspeichers, wobei z. B. kaltes Medium konsequent in die untere Speicherzone eingespeist wird, erfolgt nicht.
• • Die Frage der geringstmöglichen Brennerleistung und die damit in Zusammenhang stehende Bevorratung von Wärme in einer Warmzone, sowie die Notwenigkeit einer (ausreichend bemessenen) Kaltzone wird nicht behandelt. Diese ist aber von wesentlicher Bedeutung, da dadurch die Funktion und die Effizienz des Gerätes wesentlich bestimmt wird,
• • Die zusätzliche, technisch sinnvolle Einbindung einer thermischen Solaranlage ist meist nicht Gegenstand vergleichbarer Ansätze.

Comparable approaches have, among other things, the following defects or deviations:

• • The downward guidance of the hot gases in the storage medium does not take place in a large-area heat exchanger,
• • A consistent distinction between upper hot zone and lower cold zone of the water reservoir, where z. B. cold medium is consistently fed into the lower storage zone does not occur.
• • The issue of the lowest possible burner output and the associated storage of heat in a hot zone, as well as the need for a (sufficiently) cold zone is not dealt with. However, this is essential because it significantly determines the function and efficiency of the device,
• • The additional, technically meaningful integration of a solar thermal system is usually not the subject of comparable approaches.

problem

• • die geringe Effizienz von Brennwertheizgeräten insbesondere während der Trinkwarmwassererzeugung zu beheben,
• • das Potential eines hocheffizienten Wärmeerzeugerbetriebs bei der Trinkwarmwassererzeugung auch für einen effizienteren Heizbetrieb zu nutzen,
• • die in Neubauten ab 2009 gesetzlich vorgeschriebene Nutzung regenerativer Energien in Form von Solarenergie als festen Bestandteil in das Gerät zu integrieren,
• • ein Gerät darzustellen, welches deutlich einfacher ist in Aufbau, Regelbarkeit und Herstellung als derzeitige Geräte,
• • ein Gerät darzustellen, welches kompakter und preiswerter ist als Heizgeräte mit separaten Speichern für die Trinkwarmwassererzeugung und weiteren separaten Komponenten für die solare Trinkwarmwassererzeugung und Heizungsunterstützung,
• • den Bedarf an elektrischer Hilfsenergie zu reduzieren, z. B. durch Reduzierung des wasserseitigen Druckverlustes und des regeltechnischen Aufwands,
• • durch eine der geringen Heizlast moderner Gebäude angepasste, kleinstmögliche Brennerleistung sicherzustellen, dass die Brennermodulation tatsächlich der Anpassung an kleinere Heizlasten bei steigenden Außentemperaturen dient.

The problem was to

• • remedy the low efficiency of condensing boilers, especially during domestic hot water production,
• • to use the potential of high-efficiency heat generator operation in domestic hot water production also for more efficient heating operation,
• • to integrate the legally prescribed use of renewable energy in the form of solar energy as a permanent component in new buildings from 2009 into the device,
• • represent a device that is much simpler in design, controllability and manufacturing than current devices,
• • to present a device that is more compact and less expensive than heaters with separate storage tanks for domestic hot water production and other separate components for solar domestic hot water production and heating support,
• • reduce the need for electrical power, eg. B. by reducing the water-side pressure loss and the control engineering effort,
• • To ensure the lowest possible burner output, adapted to the low heat load of modern buildings, so that the burner modulation actually adapts to smaller heating loads with increasing outside temperatures.

the solution of the problem

The basic idea is a device that is based on the principle of a direct-fired hot water tank, which initially all harmful effects associated with low water content of conventional heaters (high pressure drop, limitation of spread, minimum return temperature, technical control effort, performance premium for drinking water production, etc.) are fixed.

• • Feuerraum mit Brenner für flüssige oder gasförmige Brennstoffe mit kleinstmöglicher Brennerleistung und modulierender Betriebsweise zur Erreichung langer Brennerlaufzeiten, wodurch sich das Gerät insbesondere für Gebäude mit hohem Wärmeschutzstandard (bzw. kleinen Heizlasten) eignet,
• • Mindestens zwei Temperaturzonen (Warm- und Kaltzone)
• • Abgaswärmetauscher in der unteren Kaltzone des Speichers zur weitgehenden Ausnutzung der sensiblen und insbesondere latenten Restwärme im Heizgas (Brennwerttechnik) in allen Betriebszuständen (Heiz- und Trinkwarmwasserbetrieb),
• • Möglichkeit der Auskopplung von Trinkwarmwasser und Heizwärme,
• • Möglichkeit der Nutzung von thermischer Solarenergie.

Based on that were to integrate:

• • combustion chamber with burner for liquid or gaseous fuels with the lowest possible burner output and modulating operation to achieve long burner run times, making the unit particularly suitable for buildings with high heat protection standard (or small heating loads),
• • At least two temperature zones (hot and cold zones)
• • Exhaust gas heat exchanger in the lower cold zone of the store for the extensive utilization of the sensitive and in particular latent residual heat in the heating gas (condensing boiler technology) in all operating states (heating and domestic hot water operation),
• • Possibility of extracting domestic hot water and heating heat,
• • Possibility of using solar thermal energy.

The store can drinking water or alternatively -. B. for reasons of hygiene - store heating water by means of which in another heat exchanger of any type (eg integrated heat exchanger according to the flow principle or external heat exchanger as a so-called fresh water station) drinking water is generated. In both cases, the lower storage zone (cold zone) is cooled: in the first case by cold drinking water, which flows in hot water tap directly into the cold zone, in the second case by heating water, which has been cooled by heat exchange with nachströmendem cold drinking water. The basic principle of offering both the exhaust gas heat exchanger and the solar heat exchanger cold storage medium for heat exchange and for highly efficient energy utilization, and this in all operating conditions, remains in both cases.

By minimizing the burner output, the heating of the cold zone is very slow, so that for long periods (many hours, ideally until the next peak tapping with renewed cooling of the cold zone) a cooling of the downstream flowing in the exhaust gas heat exchanger heating gases below the heating circuit return temperatures is possible.

For the first time, the burner and the solar system work according to the same principle: The heating of the storage medium is achieved by long charging times and low heat generator capacities. The solar system as well as the heating gases (after leaving the combustion chamber) work on the cold zone, whose low temperatures allow a substantial cooling of the hot gases and thus a high heat utilization of the fuel (heating period) as well as an efficient operation of the solar system by low system temperatures (summer operation), regardless of whether the device is in heating or DHW mode. It is then possible (and intended) that the heating gas in heating operation reaches a lower temperature than the heating circuit return.

Due to the large amounts of water surrounding the combustion chamber and the exhaust gas heat exchanger in the cold zone of the storage, safety measures for forced flow through the water space can be omitted. Instead, the principle of gravity is used for water-side flow around the heat exchanger with elimination of electrical auxiliary power (pump power). Large heat exchanger surfaces can be realized.

• 1. Die Brennerleistung wird auf eine kleinstmögliche Leistung, nahe dem jeweiligen Wärmebedarf für die Raumheizung, begrenzt. Leistungszuschläge für die Trinkwarmwassererzeugung können minimiert werden, da das Gerät große Wärmemengen vorhält. Brennerstarts werden minimiert.
• 2. Das Speichervolumen wird so bemessen, dass Bedarfsspitzen (insbesondere des Trinkwarmwasserbedarfs) über das Speichervolumen und nicht über die Wärmeerzeugerleistung gedeckt werden (mindestens eine Spitzenzapfung wird komplett bevorratet). Dadurch ist es möglich, den Speicher mit geringsten Brennerleistungen über lange Laufzeiten nachzuladen.
• 3. Eine angeschlossene Solaranlage kann bei entsprechender solarer Einstrahlung die Brennerleistung bzw. die Betriebszeiten des Brenners reduzieren, bzw. den Brennerbetrieb überflüssig machen, und somit weiteren Brennstoff einsparen.
• 4. Der Feuerraum mit Brenner begrenzt die obere Warmzone des Speichers nach unten hin, wobei die Heizgase den überwiegenden Teil ihres Wärmeinhalts an das Speichermedium in der Warmzone abgeben und diese auf Solltemperatur halten. Innerhalb der Warmzone können sich, z. B. je nach Temperaturanforderungen und Anordnung der Temperaturfühler für Heiz- und Trinkwarmwasserbetrieb, weitere Schichten mit unterschiedlichen Temperaturen ergeben. Der Speicher enthält unterhalb des Feuerraums eine Kaltzone. Mit der Restwärme der Heizgase wird mittels eines Abgaswärmetauschers, der sich in dieser Kaltzone befindet, ständig kaltes Speichermedium vorgewärmt. Dadurch ist der Betrieb des Gerätes immer hocheffizient, und zwar unabhängig davon, ob es sich im Heiz- oder Trinkwarmwasserbetrieb befindet. Ebenfalls auf diese Kaltzone arbeitet ein weiterer Wärmetauscher beliebiger Bauart (integriert oder extern) zur Einkopplung von Wärme, die in Solarkollektoren beliebiger Bauart erzeugt wurde.
• 5. Heizwärme wird (je nach Speichermedium direkt oder mittels mindestens eines Wärmetauschers) aus dem Speicher ausgekoppelt. Der witterungsgeführte Betrieb, d. h. die Absenkung der Vorlauftemperatur mit steigender Außentemperatur, kann über Mischer beliebiger Bauart erfolgen.

The following measures are combined in the device described here:

• 1. The burner output is limited to the lowest possible power, close to the respective heat demand for space heating. Performance surcharges for domestic hot water production can be minimized because the unit holds large amounts of heat. Burner starts are minimized.
• 2. The storage volume is calculated in such a way that demand peaks (in particular of the domestic hot water requirement) are covered by the storage volume and not by the heat generator output (at least one tip tap is completely stored). This makes it possible to recharge the memory with minimum burner performance over long periods.
• 3. A connected solar system can reduce the burner output or the operating times of the burner with appropriate solar irradiation, or make the burner operation unnecessary, and thus save more fuel.
• 4. The combustion chamber with burner limits the upper warm zone of the store downwards, whereby the hot gases deliver the majority of their heat content to the storage medium in the warm zone and keep it at the set temperature. Within the warm zone, z. B. depending on the temperature requirements and arrangement of the temperature sensor for heating and domestic hot water operation, more layers with different temperatures. The store contains a cold zone below the firebox. With the residual heat of the hot gases is constantly preheated by means of an exhaust gas heat exchanger, which is located in this cold zone, cold storage medium. As a result, the operation of the device is always highly efficient, regardless of whether it is in heating or domestic hot water operation. Also on this cold zone, another heat exchanger of any type (integrated or external) works for the coupling of heat generated in solar collectors of any design.
• 5. Heating energy is (depending on the storage medium directly or by means of at least one heat exchanger) decoupled from the memory. Weather-compensated operation, ie the lowering of the flow temperature with increasing outside temperature, can take place via mixers of any type.

Explanation with reference to three exemplary embodiments (with reference to FIGS. 1 a, 1 b, 1 c, 2 a and 2 b)

Construction:

• • ein Feuerraum [5] mit Gebläsebrenner [4], durch den in der oberen Warmzone des Speichers definierte Solltemperaturen gehalten werden (der Feuerraum sollte Gefälle in Richtung des Abgaswärmetauschers zwecks Ableitung des Kondensates aufweisen). Die Ableitung der Abgase des Gebläsebrenners kann – in den Abbildungen nicht dargestellt – herkömmlich über Brennwert-Abgassysteme über Dach oder vorzugsweise über die Fassade erfolgen. Die Zuluft für den Gebläsebrenner kann raumluftabhängig, d. h. aus dem Aufstellraum des Gerätes, oder vorzugsweise raumluftunabhängig, d. h. über die Außenluft mittels separatem Zuluftrohr oder kombinierten Luft-Abgas-Systemen [10, 31], erfolgen.
• • ein Abgaswärmetauscher [6] zur Vorwärmung des Speichermediums in der unteren Kaltzone (Rohrwendel-Wärmetauscher, Prinzip einer Nachschaltheizfläche); das Heizgas wird danach über den Kondensatabscheider [9] in das Abgassystem [10] geführt. Der Abgaswärmetauscher weist durchgängiges Gefälle zwecks Ableitung des Kondensates auf und kann Einsätze zur Verbesserung des Wärmeüberganges enthalten,
• • ein Wärmetauscher [8] zur Einkopplung von Wärme aus einer solarthermischen Anlage [20, 21] über entsprechende Anschlüsse [22] in die Kaltzone (andere Bauarten und Anordnungen (z. B. extern) sind möglich).

The central component is first a water reservoir [2] with highly effective thermal protection [3] for storing storage medium to be heated [1]. In it are housed:

• • a combustion chamber [5] with forced-air burner [4], by which the setpoint temperatures defined in the upper warm zone of the storage tank are kept (the combustion chamber should have a slope in the direction of the exhaust gas heat exchanger for the discharge of the condensate). The discharge of the exhaust gases of the fan burner can - not shown in the figures - conventionally via condensing gas systems via roof or preferably on the facade. The supply air for the fan burner can room air-dependent, ie from the installation room of the device, or preferably room air independent, ie on the outside air by means of separate Zuluftrohr or combined air-exhaust systems [10, 31], take place.
• • an exhaust gas heat exchanger [6] for preheating the storage medium in the lower cold zone (coiled tubing heat exchanger, principle of a Nachschaltheizfläche); the heating gas is then passed through the condensate trap [9] into the exhaust system [10]. The exhaust gas heat exchanger has a continuous gradient for the purpose of discharging the condensate and may contain heat transfer enhancements.
• A heat exchanger [8] for coupling heat from a solar thermal system [20, 21] via corresponding connections [22] into the cold zone (other designs and arrangements (eg external) are possible).

The 1a . 1b and 1c show the device in embodiments in which drinking water is used as a storage medium. In this case, at least one additional heat exchanger is required to extract heat from heating [7]. will over. The upper connection [12] serves for the extraction of domestic hot water for the taps [23] from the warm zone of the storage tank. The lower connection [11] is used for the subsequent flow of cold drinking water (the connection of a circulation line [13] with circulation pump [19] is shown by way of example).

The 1a shows the device in the embodiment in which the heating circuit flow temperature is below the domestic hot water temperature (setpoint). Here, the heating heat from the hot zone via at least one heat exchanger [7] is decoupled (shown here by way of example in an integrated arrangement).

The 1b shows the device in the embodiment in which the heating circuit flow temperature is higher than the domestic hot water temperature (setpoint). Here, the combustion chamber [5] is directly surrounded by the heating medium, which supplies the heating circuit (s) [14, 15] with heat, and which transfers excess heat to the storage medium (drinking water) via an outer wall.

The 1c shows the device in a variant with a second, additionally arranged below in the cold zone heat exchanger for the extraction of heat [28]. On this, the heating circuit return can be switched by means of an actuator [29] when the cold zone temporarily -. B. in the absence of domestic hot water tap - should assume higher temperatures than the heating circuit return. The temperature stratification of Memory is then retained even in this case. The flow of this second heat exchanger can be fed into the return, or alternatively in the flow, of the upper heat exchanger for heating heat extraction [30]. The actuator [29] is operated accordingly as a switching or mixing element.

The 2a and 2 B show variants in which heating water is used as a storage medium. In this case, heat can be removed directly as heating water and z. B. a Heizkreisverteiler [14, 15] are supplied.

Domestic hot water is generated in this case via at least one heat exchanger.

The 2a shows an external heat exchanger [26] (so-called fresh water station).

The 2 B shows a built-in memory heat exchanger for domestic hot water production in the flow principle ([26] in 2 B , for clarity's sake, cut open in the lower part).

• • die Heizkreise beispielhaft dargestellt durch eine Heizkreispumpe [17], einen Mischer [16], einen Heizkörper mit Thermostatventil [18] sowie einen Verteiler [14, 15], können jedoch auf beliebige Weise ausgeführt sein,
• • die Komponenten der thermischen Solaranlage vereinfacht und beispielhaft dargestellt durch einen Solarkollektor [21], eine Solarstation mit Umwälzpumpe, Druckabsicherung etc. [20] sowie einem Wärmetauscher [8]; der Solarkreis wird in diesem Beispiel mit einem eigenen, geschlossenen Kreislauf betrieben,
• • eine oder mehrere beliebige Zapfstelle(-n) für Trinkwarmwasser beispielhaft dargestellt durch eine Dusche [23].

Furthermore, in 1a . 1b . 1c . 2a and 2 B

• • the heating circuits are exemplified by a heating circuit pump [17], a mixer [16], a radiator with a thermostatic valve [18] and a distributor [14, 15], but can be designed in any way,
• • The components of the solar thermal system simplified and exemplified by a solar collector [21], a solar station with circulation pump, pressure protection, etc. [20] and a heat exchanger [8]; the solar circuit is operated in this example with its own closed circuit,
• • One or more taps (-n) for drinking hot water exemplified by a shower [23].

Function:

First, a liquid or gaseous fuel is burned in a forced air burner [4], generating hot gases whose sensible and latent heat is to be exploited to the maximum.

The device described here is characterized in that the hot gases first give off a large part of the heat in the combustion chamber [5] to the surrounding medium [1] and thus heat the upper, at least to a domestic hot water demand peak measured hot zone to target temperature, then after leaving the Combustion furnace in an exhaust gas heat exchanger [6] are guided downward, wherein the residual heat contained in the heating gas is transferred to the storage medium in the lower cold zone. This is preheated and moves upwards by the principle of gravity. The hot gases are lowered as much as possible to the temperature level of the cold zone, regardless of whether the unit is in heating mode or nachwärt domestic hot water.

On the one hand, the cross-flow and countercurrent heat exchanger principle is used for a good heat transfer, on the other hand, the hot gases leave the exhaust gas heat exchanger at a deep in the memory location where their cooling is almost possible to the lowest temperature level of the cold zone. Due to the continuous gradient, the condensate formed when using the latent heat in the exhaust gas heat exchanger [6] is discharged to the condensate separator [9].

On the cold zone of the memory works another heat exchanger for coupling heat from a solar thermal system of any type [8]. The heated storage medium also moves upwards by the principle of gravity. The possibly required heating of the storage medium to the final temperature to be reached takes place only in the upper hot zone, with the vast majority of the burner power. There, the storage medium [1] is kept at the set temperature.

Basically, there are two options for heating heat extraction:

Variant in 1 : The storage tank stores drinking water which, when tapped at at least one tapping point [23], exits the store warmly via an upper connection [12], with cold drinking water flowing in via a lower connection [11]. Heating heat is transferred via at least one further heat exchanger [7] ( 1a ), or from a heating water space surrounding the combustion chamber ( 1b ) decoupled. The arrangements and types of this heat exchanger are determined here by the heating circuit flow temperature to be reached. If necessary, the heating heat extraction also takes place via further heat exchangers [28], if z. B. heat from different storage zones - depending on the temperature conditions - to be coupled ( 1c ). A weather-dependent setting of the heating water flow temperature (-en) can be made via one or more mixers [16].

Variant in 2 : The storage stores heating water. Domestic hot water is generated by at least one additional heat exchanger [26]. The 2a shows here by way of example and simplifies an externally mounted plate heat exchanger, which symbolizes a so-called fresh water station here. When the domestic hot water tap is warm hot water on the upper connection [24] pumped into this heat exchanger on the primary side. The return is recycled at low temperature into the lower cold zone of the storage [25], if necessary, a stratified recycling takes place. On the secondary side, cold drinking water enters this heat exchanger [11], leaves the heat exchanger [12] and flows to the tap (s) [23].

2 B shows here by way of example and simplifies integrated into the memory heat exchanger for drinking water production in Durchflußprinzip. Cold drinking water enters the integrated heat exchanger via the lower connection [11] and is removed via an upper connection [12].

In these cases, the in 2a and 2 B are shown, the heating heat for space heating directly, ie without heat exchanger, can be decoupled from the hot zone of the memory by removing the storage medium [14, 15]. The heating circuit return can be returned by different measures at different levels - depending on the temperature - in the memory, here exemplified by a feed shaft (an external switching valve for stratifying the return to different storage levels is possible, mutatis mutandis, as in 1c ). Also in these in 2a and 2 B shown embodiments, a weather-dependent adjustment of the heating circuit flow temperature (-en) via one or more mixers [16].

The device is thus operated as a condensing boiler, the heating gas temperatures are well below those of current condensing boilers - and in particular often below the return temperatures of the heating system.

• • je geringer die Brennerleistung ist,
• • je größer das Speichervolumen ist,
• • je größer der Wärmebedarf für Trinkwarmwasser im Verhältnis zum Heizwärmebedarf ist,
• • je langer die Brennerlaufzeiten sind,
• • je niedriger die Temperatur in der unteren Kaltzone bleibt, insbesondere in Zeiten hoher Heizleistung (in der zudem kein Solarertrag zu erwarten ist),
• • Je mehr solare Wärme zur Erreichung der Solltemperatur genutzt werden kann.

The efficiency of this device (in terms of low fuel consumption in relation to the amount of useful heat generated) is better,

• • the lower the burner power,
• • the larger the storage volume,
• • the greater the heat requirement for domestic hot water in relation to the heating requirement,
• • the longer the burner run times,
• • the lower the temperature remains in the lower cold zone, especially in times of high heat output (in which no solar yield is to be expected),
• • The more solar heat can be used to reach the setpoint temperature.

• • Das Gerät zeichnet sich durch einfachen, nachvollziehbaren Aufbau aus.
• • Das Gerät vereint Wärmeerzeuger (Heizkessel), Trinkwarmwasserspeicher und Solarspeicher und besitzt dadurch einen sehr geringen Platzbedarf sowie sehr geringe Bereitschaftsverluste.
• • Bedarfsspitzen werden in der Warmzone bevorratet und erfordern keine erhöhte Brennerleistung
• • Obwohl die Einkopplung solarthermischer Energie nur über einen einzelnen Wärmetauscher erfolgt, ist der solare Ertrag sowohl für die Trinkwarmwassererzeugung als auch für die Heizungsunterstützung nutzbar.
• • Das Gerät benötigt keine aufwändige Regeltechnik.
• • Das Gerät kann weitgehend unter Verwendung bereits verfügbarer Einzelkomponenten dargestellt werden.
• • Der zu erwartende Verkaufspreis dürfte unterhalb dem einer Kombination der Einzelgeräte Brennwertkessel + Trinkwarmwasserspeicher + Solarspeicher liegen, dagegen ist eine deutliche Effizienzsteigerung zu erwarten (mehr Effizienz ohne Mehrinvestition). Das Gerät ist damit in hohem Maße wirtschaftlich.
• • Hinsichtlich der sicherheitstechnischen Anforderungen und Betriebsbedingungen ist dieses Gerät im Vergleich zu kompakten Wärmeerzeugern nach dem Stand der Technik anspruchslos.
• • Durch die geringe Brennerleistung ist der Brennstoffverbrauch selbst bei nicht optimaler Einstellung nach oben begrenzt.
• • Das Gerät benötigt aufgrund geringster Druckverluste wenig hydraulische Leistung und damit wenig elektrische Hilfsenergie.
• • Es sind nur wenige Pumpen erforderlich.
• • Bei der Auslegung der Heizanlage für ein Gebäude muß nicht zwingend Wert gelegt werden auf kostenintensivere Heizsysteme mit geringen Systemtemperaturen (z. B. Fußbodenheizung), da die Abgastemperatur im Wesentlichen von der Temperatur in der Kaltzone, und diese wiederum vom Trinkwarmwasserbedarf bestimmt wird.
• • Aufstellung und Installation sind sehr einfach. Angeschlossen werden lediglich – Kaltwasserzulauf (Trinkwasser) und Trinkwarmwasserentnahme (ggf. Zirkulation), – Heizungsvor- und Rücklauf, – Solarkreisvor- und Rücklauf – Elektrischer Anschluß (Regelung, Pumpe, Mischer) – Abgasrohr, ggf. Zuluftrohr

Advantages of the device:

• • The device is characterized by simple, comprehensible construction.
• • The unit combines heat generator (boiler), domestic hot water tank and solar storage tank and therefore has a very small footprint and very low standby losses.
• • Demand peaks are stored in the hot zone and do not require increased burner output
• • Although the solar thermal energy is only injected via a single heat exchanger, the solar yield can be used both for domestic hot water production and for heating support.
• • The device does not require complex control technology.
• • The device can largely be displayed using already available individual components.
• • The expected sales price is likely to be below that of a combination of the single units condensing boiler + domestic hot water tank + solar storage, however, a significant increase in efficiency is expected (more efficiency without additional investment). The device is thus highly economical.
• • With regard to the safety requirements and operating conditions, this device is undemanding in comparison to compact state-of-the-art heat generators.
• • Due to the low burner performance, the fuel consumption is limited even at a non-optimal setting.
• • The device requires little hydraulic power due to the lowest pressure losses and therefore little auxiliary power.
• • Only a few pumps are required.
• • When designing the heating system for a building, there is no need to emphasize more costly heating systems with low system temperatures (eg underfloor heating), as the exhaust gas temperature is essentially determined by the temperature in the cold zone, which in turn depends on the domestic hot water demand.
• • Installation and installation are very simple. Only connected - Cold water inlet (drinking water) and domestic hot water (possibly circulation), - Heating flow and return, - Solar circuit flow and return - Electrical connection (control, pump, mixer) - Exhaust pipe, possibly supply air pipe

LIST OF REFERENCE NUMBERS

1

storage medium

2

Speicherwandung

3

heat protection

4

blowpipe

5

firebox

6

Exhaust gas heat exchanger

7

Heat exchanger heating water

8th

Solar heat exchanger

9

condensate

10

Access exhaust / connection to exhaust system

11

Entry drinking water (cold)

12

Outlet drinking water

13

Admission circulation

14

Heating flow

15

Heating return

16

Mixer for weather-controlled operation

17

Heating circuit

18

Radiator, symbolic of any heat transfer to room

19

Circulation pump (optional)

20

Solar pump group

21

solar collector

22

Connection of solar circuit to solar heat exchanger

23

Tap hot water

24

Supply of drinking water

25

Return DHW watering

26

Heat exchanger for domestic hot water production

27

Return feed with stratified charging device

28

second heat exchanger heating water

29

Mixer for integration of the second heat exchanger heating water

30

Connection flow from the second heat exchanger heating water (alternative)

31

Combustion air supply to the burner

Claims (3)

Highly efficient, solar-assisted condensing storage heater for liquid or gaseous fuels for generating domestic hot water and heating heat for space heating, characterized in that in a cylindrical, standing water storage • has a warm zone in the upper part, which stores sufficient heat for at least one hot tap top hot water , and from the lower part heating warmth can be coupled for space heating, which is mixed by means of mixer to the respective required flow temperature, • approximately in the middle part has a firebox that limits the hot zone down and this according to the required set temperatures for domestic hot water and space heating on Heated natural circulation. In the combustion chamber is the burner, which is operated with the lowest possible burner output and thus long burner run times, • in the lower part of a generated in particular by drinking hot water tap cold drinking water generated cold zone in which an exhaust gas heat exchanger and a solar heat exchanger is located, the hot gases after leaving the furnace down in the arranged in the cold zone exhaust gas heat exchanger and cooled to low temperatures. This happens regardless of whether the device is currently in the domestic hot water or heating mode. In particular, the hot gases can assume temperatures below the heating circuit return temperature, whereby a significantly higher heat utilization of the hot gases is possible. By heat release of the hot gases by utilizing their sensible and latent residual heat (condensing operation), the storage medium of the cold zone is preheated to a low temperature level. The cold zone is dimensioned so that in the case of exclusive burner operation (winter operation), the temperature of which, if possible, does not reach the level of the warm zone, even in the normally expected tapping pauses. The exhaust gas heat exchanger is designed as an efficient, corrosion resistant and easy to clean coiled tubing smooth tube heat exchanger with continuous slope for condensate drainage and can contain inserts to increase turbulence. The hot gases leave the exhaust gas heat exchanger via a condensate and then enter an exhaust system, which can be room air independent (air exhaust system with integrated combustion air supply, or separate combustion air supply) or room air dependent (combustion air supply from the installation room). The cold zone is - with appropriate solar radiation supply - supplied via another heat exchanger of any type heat from solar panels, which is then available for both the domestic hot water generation and for the heating support. Outside of winter operation, the achievement of higher temperatures in the memory by the solar system is desirable to achieve shutdown of the burner. All consumer-side connections are arranged in a consistent manner so that the stratification is maintained in upper hot and lower cold zone. For this purpose, if necessary, stratified charge devices are used. Highly efficient condensing storage heater according to claim 1, characterized in that there is drinking water in the memory, and the decoupling of heating by at least one heat exchanger of any type from the lower part of the hot zone. Additional heat exchangers in other storage zones are possible. The medium flowing into the lower storage zone (cold zone) is cold drinking water (see 1a ). Because of the thermal stratification and the desired, low burner performance come to a possibly required sanitation only other than thermal process into consideration High-efficiency condensing storage heater according to claim 1, characterized in that - in particular for hygienic reasons - heating water is in the memory, wherein domestic hot water via at least one heat exchanger Any type and arrangement (eg integrated heat exchanger (flow principle) or external heat exchanger as a so-called fresh water station) is generated. The decoupling of heat can be done directly, ie by heating water extraction and without heat exchanger, incidentally, as described in 2. below. The lower storage zone (cold zone) is kept at a low temperature by the cold return from the heat exchanger for domestic hot water production.

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