EP2317254A2 - Explosion-proof cooling assembly with combustible cooling agent - Google Patents

Abstract

The plant (1) has a gas-proof housing (23) in which a suction device (27), a gas sensor (31) and a refrigerant circuit are arranged. An air-subjected heat exchanger is formed as a condenser and arranged outside the housing. A control device separates all plant components arranged within the housing from the current supply, when reaching a preset concentration of refrigerant gas in an atmosphere of the housing. An explosion-proof ventilator (28) is operated such that the atmosphere enriched with the refrigerant gas is utilized within an environment of the housing.

Description

The invention relates to an explosion-proof refrigeration system with combustible refrigerant. The refrigerant circuit of the refrigeration system is disposed within a housing, which also has a suction device and a gas sensor. By means of a control device ensures that upon reaching a predetermined concentration of refrigerant gas in the atmosphere of the enclosure all disposed within the housing components of the explosion-proof refrigeration system are disconnected from the power supply and the operation of an explosion-proof fan is triggered. The refrigeration system is used for cooling, air conditioning and heating and includes a heat pump circuit.

When using flammable refrigerants, for example hydrocarbons, such as propane, butane or the like, in refrigeration systems, the equipment may pose an explosion hazard. As a result of leaks, the combustible refrigerant can escape from the supposedly dense refrigerant circuit and, in conjunction with the oxygen from the ambient air, create an explosive atmosphere.

In order to create an explosive atmosphere, the combustible substance must be present in an appropriate mixing ratio with oxygen. In addition, the presence of a corresponding ignition source is necessary for the triggering of an explosion. In addition to open flames, hot surfaces or visible sparks generated electrically or mechanically, discharges of static electricity, such as even very small ignition energies through clothing, electrical equalizing currents, ultrasound, electromagnetic radiation, shockwaves and adiabatic compression, can trigger explosions.

The ATEX Europe Directive requires operators of equipment to avoid explosions and to ensure adequate protection. ATEX stands for "ATmosphere EXplosive" and applies to all machine components and controls used in explosive atmospheres. With regard to explosion protection in a potentially explosive atmosphere, the ATEX directives 94/9 / EC and 1999/92 / EC have priority over machine guidelines and must always be applied. The ATEX guidelines require documentation on the frequency of occurrence of an explosive atmosphere and their spatial delimitation. These areas should be zoned according to the specification. Furthermore, it must be ensured that only the correct category is used in this zone type corresponding components. Once an area is classified as dangerous, it will determine the necessary restrictions on potential sources of ignition that might be present in that area.

Various protection principles can be divided. The greatest protection is afforded by systems with primary explosion protection, in which the possibility of forming an explosive atmosphere is ruled out in advance. Primary explosion protection includes the use of non-combustible substitutes or the prevention of explosive mixtures through aeration or concentration change.

If primary explosion protection is not possible, ignition of the potentially explosive atmosphere as secondary explosion protection must be avoided. The secondary explosion protection includes the use of appropriate equipment, components and materials or instructions for the stay in hazardous areas.

The third measure is to limit the effects of an explosion to an acceptable level. For this purpose, appropriate encapsulations of the system or its installation site must be taken into account.

All equipment installed in an explosive atmosphere must comply with the ATEX conditions as far as they are operated within the European Union. According to the ATEX guidelines, all electrical and electrical systems are basically to consider mechanical devices. The equipment referred to in Directive 94/9 / EC includes machinery, equipment, stationary or portable equipment, control and equipment components and warning and preventive systems, used individually or in combination to generate, transmit, store, measure, regulate and convert energies and / or or intended for the processing of materials and have their own potential sources of ignition and thereby may cause an explosion into consideration. Thus, almost all components of a refrigeration system, such as compressors, evaporators and condenser, but also valves, pressure gauges, sensors and the like, fall within the scope of the ATEX directives. As a result, components marked accordingly and provided with the required documentation, for example the manufacturer's relationship or declaration of conformity, must be used by the plant manufacturer.

The explanations of the component manufacturers relate only to the individual components. It is assumed that during installation and during operation the corresponding installation standards as well as installation and operating instructions, for example the operating instructions, are complied with. The interactions between different components of the refrigeration system with the environment, especially with regard to potential sources of ignition, must be assessed by the system manufacturer. If the assessment is positive, the plant manufacturer must provide a corresponding explanation for the equipment group or installation. The operator must report the equipment to the supervising body and request any necessary acceptance.

The operator obligations also include the creation of a so-called explosion protection document. This is regulated in the ATEX 137. This includes, among other things, an assessment of the explosion risks. Depending on the frequency and duration of the occurrence of an explosive atmosphere, potentially explosive areas must be divided into zones and marked accordingly.

• ständig, über lange Zeiträume oder häufig vorhanden (Zone 0),
• bei Normalbetrieb gelegentlich vorhanden (Zone 1) und
• bei Normalbetrieb nicht oder aber nur kurzzeitig vorhanden (Zone 2).

Des Weiteren sind die für den Explosionsschutz wichtigen Eigenschaften des Stoffes oder der Stoffe zu deklarieren. Daraus ergeben sich die Voraussetzungen für die einzusetzenden Komponenten (Gruppe, Kategorie, Unterexplosionsgruppe, Temperaturklasse).An explosive atmosphere is

• permanently, over long periods of time or frequently (zone 0),
• occasionally present in normal operation (zone 1) and
• during normal operation, or only for a short time (zone 2).

Furthermore, the properties of the substance or substances important for explosion protection must be declared. This results in the prerequisites for the components to be used (group, category, sub-explosion group, temperature class).

Refrigerant systems with flammable refrigerants, for example hydrocarbons, such as propane, butane or the like, thus fall within the scope of the ATEX directives for the intended use of equipment and protective systems in potentially explosive atmospheres. Due to the above-mentioned zone definition, the use of hydrocarbons as a refrigerant also requires zoning. In this case, at least of zone 2 in the vicinity of the system is usually assumed, since leakage can not be completely excluded. Therefore, according to the ATEX guidelines, certain devices must be used for the declared zone.

As a result of the classification of the refrigeration system in the ATEX directives arise when using, for example, hydrocarbons as refrigerant considerable disadvantages in terms of securing the system and its environment. The establishment of the refrigeration system is associated with a very large overhead in material costs compared to a conventional, filled with a non-flammable refrigerant comparable facility, since only labeled and provided with a required documentation components are to be used. In addition, the construction of the system requires compliance with a number of provisions, so that the time required for the construction and operation of the system is much higher than in comparable systems with incombustible refrigerants. Such are, for example Evaluate interactions between the components of the refrigeration system and the environment by the plant manufacturer and to provide a corresponding explanation for the device group or the system. The systems must be reported and any necessary acceptance must be requested. Further disadvantages are the compilation of the explosion protection document and the declaration of the properties of the substance or substances which are important for the explosion protection.

As a refrigeration system, a so-called composite refrigeration system is provided with a variety of evaporators. These systems are used for example in supermarkets in which the evaporators in so-called consumers, such as refrigerators, refrigerators and freezers, are integrated. In this case, cooling capacities are provided at different temperature levels. The different temperature levels cause different pressures during the evaporation of the refrigerant. Compound refrigeration systems consist of closed systems consisting essentially of the components evaporator, compressor, condenser and expansion element. The condenser is located at facilities in supermarkets outside the market, surrounded by outside air.

Within such a refrigerant circuit, the arrangement of a refrigerant accumulator is also known, which compensates for the differences in refrigerant amount during operation within the refrigeration system. In particular, in composite refrigeration systems in which a plurality of evaporators are operated in parallel, the use of refrigerant accumulators is necessary. A sufficient amount of refrigerant must be made available in the refrigerant circuit of a combined refrigeration system so that all evaporators can be adequately supplied, even with maximum refrigeration demand. On the other hand, with low cooling demand, in which individual evaporators are only partially filled or not charged with refrigerant, excess refrigerant must be stored. The collectors have a disadvantageous large volume, which is charged with refrigerant and with combustible Refrigerant-filled refrigeration systems drastically increases the potential for explosion in the event of leaks.

In the prior art refrigeration systems are known with a system for heat recovery. It is not the complete, resulting from high pressure heat in the condenser transferred to the ambient air. Rather, an additional heat exchanger is arranged in the flow direction of the refrigerant upstream of the original condenser. Within the additional heat exchanger, the refrigerant, which emerges as hot gas from the compressor, cooled or re-heated. The resulting heat is transferred to the system of heat recovery and used in this example, for heating a medium within a heating system.

Depending on the season and / or time of day, different cooling capacities of the consumers are needed and transferred to the refrigerant within the evaporator. The available power of the system of heat recovery is thus dependent on the total heat absorbed in the evaporators and thus also subject to the variable cooling capacities of the consumers.

Due to the variable cooling capacities of the consumers, certain operating conditions may occur in which the total amount of heat to be delivered at high pressure is insufficient to meet the heat demand of the heat recovery system. In this case, it is necessary, in addition to the refrigeration system, which also serves to generate heat, to install an additional heat generating unit, for example, a boiler to be fired. This additional installation disadvantageously adds additional investment and operational costs.

The object of the present invention is to provide an explosion-proof refrigeration system with combustible refrigerant. The Refrigeration system should be less expensive to install and operate than the systems known in the art. The extra effort compared to a comparable refrigeration system with incombustible refrigerant must be minimized. In addition, the safety of the system, especially with regard to explosion protection, to be guaranteed with minimal maintenance. The need for refrigerant within the system must be kept to a minimum. An explosion in case of leakage or leakage of the system should be excluded.

The object is achieved by an explosion-proof refrigeration system. The system comprises a housing in which a suction device, a gas sensor and a refrigerant circuit of a refrigeration system are arranged. The refrigeration system is enclosed with the refrigerant-carrying, non-explosion-proof components and their connecting elements as a coherent unit of the gas-tight housing, with only designed as a condenser air-pressurized heat exchanger is located outside the housing. The refrigerant-carrying components are not formed with a separate explosion protection.

The suction device has an explosion-proof designed fan, which is also referred to as ATEX fan.

According to the concept of the invention, a control device is additionally provided in such a way that, when a predetermined concentration of refrigerant gas in the atmosphere of the enclosure is reached, all components of the explosion-proof refrigeration system arranged inside the enclosure are switched off and disconnected from the power supply. Thus, there is no direct danger of explosion of these components due to sparking. In addition, the operation of the explosion-proof fan is triggered. Due to forced ventilation, the enriched with refrigerant gas atmosphere within the housing is spent to the outside, in the environment of the housing. In the environment becomes the refrigerant-air mixture mixed in the shortest possible time with the ambient air and thereby diluted very strong, so that no more danger of explosion of the mixture.

The concentration of the refrigerant gas in the atmosphere of the enclosure is monitored by means of one or more gas sensors disposed within the enclosure. Preferred locations of the gas sensors are areas of possible leakage points of the refrigeration system. Advantageously, the arrangement of the gas sensors in the lower part of the enclosure, since the refrigerant decreases with greater density than air within the enclosure and accumulates in particular on the ground or near the ground. The gas sensor arranged there would react to the specified increased concentration of refrigerant and trigger the safety procedures for explosion protection.

By the flow of fresh air from the environment and the extraction of the refrigerant gas enriched air from the enclosure, the concentration of refrigerant gas in the atmosphere within the enclosure in a very short time is reduced again to a minimum, so that an enrichment of refrigerant up to a explosive atmosphere is avoided. The fresh air flows through a ventilation flap, which is located in the lower part of the wall of the enclosure. By sucking in the air from the enclosure when the fan is switched on, the ventilation flap opens automatically. The ventilation flap is closed when the fan is switched off so that it is not possible to exchange air with the environment or to allow fresh air to flow after it.

Under gas-tight housing within the meaning of the invention is a encapsulation of the explosion-proof refrigeration system from the environment to understand. By separating a defined atmosphere is created to determine their composition or the concentrations of their main components well and thus to monitor are. Thus, it is advantageously possible, by means of gas sensors upon reaching a predetermined concentration of refrigerant gas in the atmosphere, to separate the components of the explosion-proof refrigeration system located within the enclosure from the power supply and to trigger the operation of the explosion-proof fan.

According to an advantageous embodiment of the invention, all connection points of the refrigerant-carrying lines of the outside of the housing arranged capacitor are housed within the housing. The refrigerant-carrying lines are soldered or welded at their connection points which are at risk for the occurrence of leakage, so that the possibility of the occurrence of leakage is minimized. The guided outside the housing, acted upon with combustible refrigerant lines are preferably made of seamless tubes, which also have no other connection points. Leakage outside the enclosure is thus almost impossible. The seamless tubes are passed through openings in the wall of the enclosure through the wall and sealed.

The explosion-proof fan is advantageously arranged within an air duct, wherein the air duct extends with an open end in the lower region of the enclosure. As the air duct is a channel in the form of a ventilation duct of an air conditioner to understand, depending on the extracted gas or gas mixture air or a refrigerant-air mixture from the housing leads into the surrounding environment.

The air duct is advantageously designed in such a way that the refrigerant-air mixture to be sucked out of the lower region of the enclosure is guided outward within the air duct over the upper region of the enclosure. The refrigerant escaping from the refrigeration system in the event of an accident or leakage accumulates as air at the bottom of the enclosure due to the greater density and is therefore to be extracted there.

According to a preferred embodiment of the invention, the air duct in the upper region of the enclosure on an additional tee. The T-piece provides a further opening of the air duct to the atmosphere within the enclosure. With the aid of the ATEX fan located within the air duct in the direction of flow of the air after the tee, the air is removed through the opening provided by the T-piece gas-tight housing sucked and discharged into the environment, which in turn leads to the compensation of the air within the gas-tight housing and the environment of the housing. This opening is used to equalize the air during normal operation of the refrigeration system, in which the heated air from the components of the refrigerant circuit accumulates in the upper part of the enclosure. The air must therefore not be enriched with refrigerant.

The upper opening of the air duct on the T-piece advantageously has a controlled ventilation flap which is closed when the fan is switched off and in the event of an accident.

According to an alternative embodiment of the invention, an additional, not explosion-proof trained fan is disposed within the upper region of an outer wall of the enclosure. The fan sucks the air in the enclosure through heat-emitting components of the refrigeration system, such as compressor, heated air, thus balancing the air within the gas-tight housing and the environment. The air does not have to be enriched with refrigerant, as in the event of leakage or damage.

The heat exchangers of the refrigeration system are connected via heat transfer circuits with the consumers, that is, for example, heat exchangers for cooling or heating in the supermarket. The heat carriers are circulated by means of pumps between the components in the circuit. The pumps are advantageously arranged within the enclosure. Only the connections of the Heat transfer circuits protrude from the gas-tight housing, which simplifies installation.

According to a preferred embodiment, the enclosure, with dimensions of about 3 m in length, 2 m in height and 2 m in width, advantageously from each other sealed areas or chambers. In a chamber all components of the refrigeration system and the pumps of the heat transfer medium circuits are arranged. This chamber is accessible through openings or doors in a vertically oriented wall of the housing. Within a further chamber, a control cabinet, which can also be walked on from outside by a control cabinet door, is likewise arranged in a vertically oriented wall of the enclosure. The separated areas of the housing are only accessible from the outside and have no connection within the housing.

Within the chamber in which the control cabinet is located, there are facilities for controlling the explosion-proof refrigeration system. In contrast to the components of the refrigeration system and the heat transfer medium circuits, the devices in the control cabinet are always connected to the power supply. In contrast, in the event of an accident, the components of the refrigeration system and the heat transfer fluid circuits are disconnected from the power supply for safety reasons.

According to a preferred embodiment of the invention, the enclosure in the lower region or at the bottom is limited by a liquid-tight tub. The liquid-tight pan prevents as part of the gas-tight enclosure the uncontrolled exchange of the atmosphere within the enclosure with the environment and on the other hand has the advantage that no liquid can escape from the enclosure, which could be caused for example by the escape of oil , The liquid can then be safely and easily removed as needed.

The refrigeration system comprising the refrigerant-loaded components and lines and their connecting elements is formed as a coherent compact unit and not destructively dismantled, since the connecting elements are designed as welded or soldered for the occurrence of leakage points welded.

With the arranged inside the housing closed refrigerant circuit of the refrigeration system is advantageously provided on the one hand, the need for cooling capacities at different temperature levels and, secondly, the need for heat output of a system of heat recovery.

The refrigerant circuit of the refrigeration system has in the flow direction of the refrigerant at least one compressor unit, a heat exchanger, which serves for the heat recovery, an air-charged capacitor, a collector, an expansion element and an evaporator. In the circuit of the refrigeration system, an evaporator of an integrated heat pump circuit with an upstream expansion element is additionally integrated, which is designed according to the concept luftbeaufschlagt. The evaporator of the heat pump circuit according to the invention with the condenser of the refrigeration system coupled thermally conductive. This double-acting heat exchanger is also referred to below as an integrated condenser-evaporator.

The operation of the system depends, among other things, on the ambient temperature and thus on the services to be provided for heating and cooling. The evaporator of the heat pump circuit is to operate in the external conditions in which the total amount of heat to be discharged at high pressure is insufficient to meet the heat demand of the heat recovery system. The amount of heat to be dispensed at high pressure results from the entirety of the Conventional refrigerant circuit recorded cooling capacities plus the introduced via the compression processes amounts of heat.

The heat generation units, such as boilers to be fired, which are required extra in conventional systems under the above operating conditions, are replaced by only one heat exchanger, which is additionally integrated in the refrigeration system. Since this heat exchanger is also connected as an evaporator of the heat pump circuit in parallel with a conventional refrigeration unit associated evaporator and thus no additional need for other components, such as a compressor, the cost of the expansion of the refrigeration system is very low.

The integrated condenser-evaporator is preferably designed as a tube bundle heat exchanger with fins. The lamellae advantageously comprise both the tubes of the evaporator of the heat pump circuit and the tubes of the condenser of the refrigeration system. By the additionally arranged tubes, on the one hand the tubes of the evaporator for the condenser and on the other the tubes of the condenser for the evaporator and the associated fins, which also thermally contact the different tubes, the area for heat transfer is increased. The fins are thermally conductively coupled to the tubes of the evaporator and the condenser. The outside air or ambient air flows through the spaces between the slats on the outside of the tubes. The refrigerant flows in each case within the tubes in the case of the evaporator of the heat pump circuit under evaporation pressure and in the case of the condenser under condensation pressure of the refrigeration system. Due to the increased area advantageously lower temperature differences result in the process of heat transfer. The process of evaporation takes place at a higher vaporization temperature and higher vapor pressure than when using a single heat exchanger with a smaller area. The pressure ratio and thus the power supplied to the compressor are lower. The coefficient of performance of the system is advantageously larger. The system works more efficiently.

The integration of evaporator and condenser within one component of the system, in addition to the lower temperature differences and thus higher energy efficiency of the entire system resulting in further advantages. Since only one integrated condenser-evaporator is used instead of two heat exchangers, all belonging to each heat exchanger peripheral equipment, such as fans and installation elements, saved. This saving is associated with significantly lower costs than when using two separate heat exchangers.

Both the evaporator of the heat pump circuit and the condenser of the refrigeration system are luftbeaufschlagte heat exchanger, both of which are each in contact with the outside air, wherein the evaporator absorbs heat from the ambient air and the condenser emits heat to the ambient air. When using the refrigeration system, for example in a supermarket, both heat exchangers would be placed independently on the outside of the building, for example on the roof or on one side of the exterior wall of the building. The advantageous combination of the heat exchanger in a single integrated condenser-evaporator can be saved in addition space.

When operating the heat pump circuit and operating conditions with temperatures of the outside air around 0 ° C and thus evaporation temperatures below 0 ° C it comes to icing of the heat exchanger surface and an increasing deterioration of heat transfer. The surfaces must be defrosted at regular intervals. The larger the area and the higher the evaporation temperature, the slower is the process of icing. Since both criteria by the refrigeration system with the double-acting heat exchanger or integrated Condenser evaporator are satisfied, the icing of the heat exchanger surface is advantageously delayed.

In addition, the temperature level of the heat exchanger is in operation as a condenser of the refrigeration system at values above ambient temperature, so that the icy surfaces can be thawed without additional facilities, such as are necessary for hot gas defrosting or for electrical defrosting. For this purpose, the integrated heat exchanger is advantageous to switch to the mode as a capacitor. The heat dissipated during condensation serves to melt the ice and evaporate the water. By dispensing with additional devices for defrosting the heat exchanger surface further costs can be saved in the material and installation costs. The operation of the system also causes less costs.

According to a preferred embodiment of the invention, the luftbeaufschlagte integrated condenser-evaporator with the downstream collector is formed in two parts and can be operated via the control of valves in different ways. Either only part of the condenser-evaporator is in operation as a condenser with the associated collector, wherein the other part of the condenser of the condenser-evaporator is not acted upon by the associated collector with refrigerant. The non-refrigerant area of the refrigeration system is separated by closed valves from the rest of the refrigerant circuit.

By separating not charged with refrigerant parts of the condenser and the collector from the rest of the refrigerant circuit in which can accumulate refrigerant, the inner volume of the refrigerant circuit can be reduced, which advantageously minimizes the amount of refrigerant or filling capacity of the system and thus the danger emanating from it Explosions significantly reduced in case of leakage or breakdown. This is in the non-operating parts of the refrigeration system accumulated refrigerant must otherwise be compensated disadvantageously by a larger capacity.

Depending on the operating mode, however, both parts of the condenser of the condenser-evaporator and the associated collector can be operated simultaneously or supplied with refrigerant.

The refrigeration system is preferably coupled with heat transfer circuits, which are used for air conditioning, cooling and heating. The evaporator of the refrigeration system, as a heat exchanger for air conditioning and normal cooling, and the heat exchanger for heat recovery or heating are designed as a refrigerant heat transfer heat exchanger. As heat transfer medium, a brine adapted to the respective conditions can be used. According to an advantageous embodiment of the invention, the headers and the returns of the heat carrier circuits for air conditioning and heating via bypasses and the heats are also connected to each other via a three-way valve. Thus, the components of the heat carrier circuits for air conditioning and heating can be acted upon depending on the operating mode or demand advantageously both with heat exchanger in the heat recovery and cooled in the evaporator of the air conditioning heat transfer. The admission is regulated by further valves.

Depending on the need for cooling capacities within the group of evaporators at the respective temperature levels, the control of the compressor capacities is simplified in that a first group of evaporators are connected via suction lines to a first compressor unit and a second group of evaporators via suction lines to a second compressor unit. Compressor units are each one or more compressors to understand, which are connected in parallel with each other. The parallel connection advantageously allows the switching on and off of compressors to the mass flows of the refrigerant and thus the cooling capacities the need of To adapt to consumers. Damaged compressors can be changed during operation of the system.

The first compressor unit thus sucks the refrigerant from the first group of evaporators and the second compressor unit from the second group of evaporators via suction lines. The refrigerant is then compressed in a common pressure line.

The evaporators of the first group and the evaporators of the second group advantageously have different temperature levels or pressure levels. Here, the first group of evaporators, the cooling capacity for the components of the normal cooling and the second group of evaporators, the cooling capacity for the components of the indoor air, with the evaporator of the integrated heat pump circuit is preferably connected in parallel to the group of compressors, the cooling capacity for the components of the indoor climate.

The evaporators of the part of the refrigeration system, which are used for normal cooling, generate the cooling capacity at a temperature level between -5 ° C and -15 ° C. The evaporators, which provide the cooling capacity of the indoor climate, operate at a temperature level between 0 ° C and 10 ° C.

Depending on the heat demand of the system of heat recovery and the operating conditions of the evaporator for the normal cooling and the indoor climate, the evaporator of the integrated heat pump circuit can be switched.

The integrated condenser-evaporator is advantageously designed switchable as needed. Thus, the evaporator of the integrated heat pump circuit by switching to operation as a condenser of the refrigeration system without additional expenditure of components and thus abtaubar without additional costs.

• Anlage derart ausgebildet, dass Einteilung der explosionsgefährdeten Bereiche in Zonen nicht erforderlich ist,
• herkömmliche, nicht explosionsgeschützte Komponenten für den Kältemittelkreislauf der Kälteanlage einsetzbar, damit wesentlich kostengünstigere Komponenten verwendbar,
• Kälteanlage ist vormontierbar und mit Kältemittel befüllbar,
• erleichterte Qualitätskontrolle, Durchführung aufwändiger Dichtigkeitsund/oder Drucktests bereits bei der Installation des Kreislaufes, Nachbearbeitung nach der Montage am Bestimmungsort entfällt,
• Durchführung der Elektroinstallation der Komponenten des Kältemittelkreislaufes beziehungsweise der Pumpen der Wärmeträgerkreisläufe bereits bei der Vormontage und damit bei Lieferung oder Montage am Bestimmungsort entbehrlich.

The following advantages can be summarized for the explosion-protected refrigeration system:

• System designed in such a way that it is not necessary to divide the potentially explosive areas into zones
• conventional, non-explosion-proof components can be used for the refrigerant circuit of the refrigeration system, so that substantially less expensive components can be used,
• Refrigeration system is pre-assembled and can be filled with refrigerant,
• eased quality control, implementation of elaborate tightness and / or pressure tests already during the installation of the circuit, post-processing after assembly at the destination omitted,
• Carrying out the electrical installation of the components of the refrigerant circuit or the pumps of the heat transfer circuits already at the pre-assembly and thus at delivery or installation at the destination unnecessary.

• weniger kostenintensiv und energetisch effektiverer Betrieb, da
  1. a) der Vorgang der Wärmeübertragung bei der Verdampfung des Kältemittels im Verdampfer der Wärmepumpenschaltung bei geringeren Temperaturdifferenzen und bei höherer Verdampfungstemperatur und höherem Verdampfungsdruck abläuft, was wiederum ein geringeres Druckverhältnis und damit eine geringere zuzuführende Leistung am Verdichter bewirkt,
  2. b) die Vereisung der Wärmeübertragerfläche im Verdampferbetrieb des integrierten Kondensator-Verdampfers verzögert wird und die vereisten Flächen ohne zusätzliche Einrichtungen und Energie abgetaut werden können,
• platzsparend und mit weniger Installationsaufwand verbunden, da auf eine große Anzahl zusätzlicher Komponenten verzichtet wird,
• Reduzierung und Minimierung der Kältemittelfüllmenge durch zweigeteilten Kondensator-Verdampfer und nachgeschaltetem Sammler sowie deren an die auftretenden Bedingungen angepassten Betriebsmodus,
• Beaufschlagung der Komponenten der Wärmeträgerkreisläufe zur Klimatisierung und zur Heizung mit erwärmtem oder mit abgekühltem Wärmeträger, sodass beispielsweise mit Wärmeträgerkreisläufen zur Klimatisierung sowohl geheizt als auch gekühlt werden kann.

The advantages of the refrigerant circuit of the refrigeration system with integrated condenser-evaporator over the systems known in the prior art are:

• less costly and energetically more effective operation, since
  1. a) the process of heat transfer during the evaporation of the refrigerant in the evaporator of the heat pump circuit runs at lower temperature differences and at higher evaporation temperature and higher evaporation pressure, which in turn causes a lower pressure ratio and thus a lower power to be supplied to the compressor,
  2. b) the icing of the heat transfer surface in the evaporator operation of the integrated condenser-evaporator is delayed and the icy surfaces can be defrosted without additional facilities and energy,
• saves space and requires less installation effort as it eliminates a large number of additional components
• Reduction and minimization of the refrigerant charge due to the two-part condenser-evaporator and downstream collector and their operating mode adapted to the conditions occurring,
• Actuation of the components of the heat carrier circuits for air conditioning and heating with heated or cooled with heat transfer, so that for example with heat transfer circuits for air conditioning both heated and can be cooled.

• Fig. 1: explosionsgeschützte Kälteanlage mit Umhausung der Komponenten des Kältemittelkreislaufes, Gassensoren, Luftkanal sowie Lüftern, Schaltschrank und luftbeaufschlagtem Kondensator-Verdampfer in der Draufsicht,
• Fig. 2: alternative Ausgestaltung der explosionsgeschützten Kälteanlage aus Fig. 1,
• Fig. 3: explosionsgeschützte Kälteanlage mit Umhausung, Gassensoren, Luftkanal sowie Lüftern und Schaltschrank in perspektivischer Ansicht,
• Fig. 4: alternative Ausgestaltung der explosionsgeschützten Kälteanlage aus Fig. 3,
• Fig. 5: Umhausung der explosionsgeschützten Kälteanlage mit Fließbild des Kältemittelkreislaufes mit integrierter Wärmepumpenschaltung,
• Fig. 6: Umhausung der explosionsgeschützten Kälteanlage mit Fließbild des Kältemittelkreislaufes mit integriertem Kondensator-Verdampfer und
• Fig. 7: Umhausung der explosionsgeschützten Kälteanlage mit Fließbild des Kältemittelkreislaufes mit zweigeteiltem integriertem Kondensator-Verdampfer.

Further details, features and advantages of the invention will become apparent from the following description with reference to the accompanying drawings. Show it:

• Fig. 1 : Explosion-proof refrigeration system with enclosure of the components of the refrigerant circuit, gas sensors, air duct and fans, control cabinet and air-operated condenser-evaporator in plan view,
• Fig. 2 : Alternative design of the explosion-proof refrigeration system Fig. 1 .
• Fig. 3 : Explosion-proof refrigeration system with housing, gas sensors, air duct, fans and control cabinet in perspective view,
• Fig. 4 : Alternative design of the explosion-proof refrigeration system Fig. 3 .
• Fig. 5 : Housing of the explosion-proof refrigeration system with flow diagram of the refrigerant circuit with integrated heat pump circuit,
• Fig. 6 : Housing of the explosion-proof refrigeration system with flow diagram of the refrigerant circuit with integrated condenser-evaporator and
• Fig. 7 : Housing of the explosion-proof refrigeration system with flow diagram of the refrigerant circuit with two-part integrated condenser-evaporator.

In Fig. 1 is the explosion-proof refrigeration system with the enclosure 23 of the components of the refrigerant circuit of the refrigeration system 1, gas sensors 31, the air duct 32 and fans 26, 28, the control cabinet 24 and the air-charged condenser-evaporator 16 shown in plan view. The refrigerant circuit of the refrigeration system 1 is filled with a combustible refrigerant such as hydrocarbon propane. The evaporators 2, 3 of the refrigeration system 1 are used in conjunction with heat transfer circuits for cooling in the supermarket and are arranged within the enclosure 23. Belonging to the heat transfer circuits pumps 21 for conveying the heat transfer between the evaporators 2, 3 and the heat exchangers within the consumer in the supermarket are also located in the enclosure 23. Only the connections of the heat carrier circuits 22, which have no direct connection to the refrigerant circuit, protrude from the enclosure 23, so that the assembly of the leads to the individual consumers simplifies outside the enclosure 23. The same applies to the heat exchanger 7 for heat recovery, which is for example also acted upon with brine or water.

The refrigerant circuit of the refrigeration system 1 is thereby advantageously preassembled and filled with refrigerant. The refrigerant circuit is closed. The quality control of the refrigeration system is facilitated. Elaborate tightness and / or pressure tests are already performed during the installation of the circuit itself. Post-processing after installation of the system at the destination is not necessary.

In addition, the components of the refrigerant circuit or the pumps 21 of the heat transfer circuits relating to electrical installation on delivery or assembly at destination is unnecessary and is already carried out during pre-assembly.

The explosion-proof refrigeration system is designed in such a way that it is not necessary to divide the potentially explosive areas into zones. So are components for the refrigerant circuit of the refrigeration system. 1 which are not subject to the scope of the ATEX directives and are thus much cheaper than components that comply with the ATEX directives.

The entire refrigerant circuit of the refrigeration system 1 is arranged as a coherent compact unit within the gas-tight enclosure 23. The enclosure 23 is arranged with a size (length x width x height) of about (3 x 2 x 2) meters outside the building, for example on the roof of the supermarket. The exact dimensions of the enclosure 23 are (3000 x 2300 x 2060) mm. The walls of the enclosure 23 are provided with 20 mm thick insulation and inside with perforated plate (not shown). The housing 23 and the condenser-evaporator 16 are mounted on a common base frame. The base frame has a length of 5725 mm and a width of 2300 mm. On the base frame transport tabs are also provided, which simplify the transport of the entire system and also allow the lifting of the system, for example, a roof safely.

Outdoor installation fulfills one of the essential measures specified by the ATEX guidelines regarding the installation site.

All piping (in Fig. 1 also not shown) are welded or soldered as connections between the various circuit components, such as heat exchangers 2, 3, 7, valves, pressure switches, control units, compressors 5, 6 and 9 collector. Leakage at the joints can thus be almost ruled out. In addition, all components, that is, their connection lines, within the housing 23.

The in Fig. 1 outside the enclosure 23 arranged air-charged integrated condenser-evaporator 16 is connected to the enclosure 23 so that all connections and interfaces of pipes and connecting lines are surrounded by the enclosure 23. The connections and interfaces have the side of the condenser-evaporator 16 forms a part of the wall of the enclosure 23. The pipes and connecting lines protrude through a wall of the condenser-evaporator 16, which is gas-tightly connected to the wall of the enclosure 23.

Within the gas-tight enclosure 23 of the explosion-proof refrigeration system 1 also gas sensors 31 are provided. In the event of an accident that can not be completely ruled out and the flammable refrigerant leaves the refrigerant circuit, the concentration of the refrigerant in the air increases. When a predetermined threshold value of the concentration is exceeded, a gas sensor 31 triggers the switching off of all components of the refrigerant circuit and of the heat carrier circuits. The components are completely disconnected from the power supply, so that these components pose no direct danger of explosion due to sparking.

At the same time, the gas sensor 31 triggers the operation of an ATEX-protected fan 28. The arranged within the suction device 27 and the air duct 32 ATEX fan 28 sucks the accumulated at the bottom of the enclosure 23, enriched with refrigerant air, that is, the refrigerant-air mixture, and it promotes according to the flow direction 29 of the air from the enclosure 23 in the environment where the refrigerant-air mixture dilutes within a very short time with ambient air to a non-explosive mixture, so that the mixture is no longer at risk of explosion. This also ensures the greatest possible protection, as the primary explosion protection of the ATEX directives, in which explosive mixtures are to be prevented by aeration or a change in the concentration. All circuit components of the refrigeration system 1 and the heat transfer medium circuits are thus advantageously not subject to the ATEX directives.

Furthermore, an additional fan 26 is disposed within the upper portion of the wall of the enclosure 23, which also does not have to comply with the ATEX guidelines. This fan 26 provides the necessary air balance between the atmosphere within the enclosure 23 and the environment. The air is conveyed in the flow direction 29 from the enclosure 23 into the environment. The air compensation is primarily for the removal of heat, which is discharged from the circuit components, in particular the compressors 5, 6, provided. In the event of an accident, the power supply of the additional fan 26 is interrupted before the ATEX fan 28 is switched on.

The fan 26 may be provided as delimitation of the atmosphere within the enclosure 23 to the environment with a ventilation flap, which is automatically opened by blowing out the air from the enclosure 23 when the fan 26 and is closed when the fan 26 is turned off, so no exchange of air with the environment is possible.

Within the housing 23, a cabinet 24 is integrated, are supplied via the all circuit components of the refrigeration system 1 with electricity, which is used to control the entire system and is completely separated spatially and gas-tight from the refrigerant circuit of the refrigeration system 1. The cabinet 24 is executed by a cabinet door 25 from the outside accessible.

The complete separation from the refrigerant circuit of the refrigeration system 1 is necessary because even in case of failure, the control cabinet 24 "in operation" remains. About the circuits and the ATEX fan 28 and components in the area outside the enclosure 23, for example, components of the heat transfer circuits, regulated.

Fig. 2 shows an alternative embodiment of the explosion-proof refrigeration system with gas-tight housing 23 of the components, gas sensors 31, air duct 32 with fan 28, walk-in control cabinet 24 and luftbeaufschlagtem condenser-evaporator 16 in plan view. The alternative embodiment of the explosion-proof refrigeration system relates to the formation of the air channel 32 in conjunction with the number and arrangement of the fan 28th

The air duct 32 has in the upper region of the enclosure 23 an additional tee 33 and thus an opening, so that the air duct 32 is formed not only in the lower region of the enclosure 32 with an opening. Due to the additional opening of the air channel 32 in the upper region of the enclosure 23, the air for the balance between the air within the gas-tight enclosure 23 and the environment using the ATEX fan 28 is sucked and conveyed in the flow direction 29 to the outside.

Due to the alternative embodiment of the explosion-proof refrigeration system of the originally integrated in the wall of the housing 23 fan 26 (see Fig. 1 ) dispensable. The function of the fan 26 is completely taken over by the ATEX fan 28.

The upper opening of the air channel 32 at the T-piece 33 is provided with a controlled ventilation flap (not shown), which is closed when the fan 28 and in case of accident. The controlled ventilation flap on the T-piece 33 is only open when only the heated by the operation of the circulating air from the gas-tight housing 23 is sucked by means of the fan 28. In the event of an accident, that is, when triggering the gas sensors 31 as well as separation of all components of the refrigerant circuit and the heat transfer fluid from the power supply or the commissioning of the ATEX fan 28, the upper opening of the air duct 32 is closed at the tee 33 through the controlled ventilation flap, so that the refrigerant-air mixture is sucked from the bottom of the enclosure 23.

In the FIGS. 3 and 4 is the explosion-proof refrigeration system shown in perspective view. The air duct 32 is guided vertically from the bottom of the enclosure 23 in the ceiling area. In the ceiling area the enclosure 23 adjoins the vertically arranged section of the air duct 32 as a 90 ° arc formed. The arc thus forms the connection between the vertically arranged section of the air channel 32 and a horizontally arranged section which, depending on the design, conveys the air or the refrigerant-air mixture in the flow direction 29 out of the enclosure 23. In the air duct 32 of the ATEX fan 28 is integrated, which sucks the air through the air duct 32.

Since the combustible refrigerant, such as hydrocarbon propane, has a greater density than air, accumulates in a leakage of the refrigerant circuit, the escaping refrigerant at the bottom of the enclosure 23. The floor is designed as a liquid-tight tray 30, which in case of emergency, for example, from the refrigerant circuit escaping oil that remains within the enclosure 23 and the environment is not polluted. The possibly leaked oil can be safely and comparatively easily removed from the tub 30.

In Fig. 3 is in the immediate vicinity of the outlet of the air channel 32 from the enclosure 23, that is in the upper region of the wall, the additional fan 26 is shown, which provides the necessary air balance between the enclosure 23 and the environment.

Fig. 4 shows an alternative embodiment of the explosion-proof refrigeration system with T-piece 33 in the upper region of the air channel 32. The suction, which is realized by the introduced in the air duct 32 tee 33, allows the extraction of air from the upper region of the enclosure 23 and leads thus saving on the additional fan 26, which also requires a further opening within the enclosure 23.

In Fig. 5 is the enclosure 23 of the explosion-proof refrigeration system with the flow diagram of the refrigerant circuit of the refrigeration system 1 with integrated heat pump circuit shown. When using the refrigeration system 1, for example, as a supermarket refrigeration system with different consumers different temperature levels, this has one or more compressors 5, 6, wherein the compressor 5 of the normal cooling circuit and the compressor 6 of the circuit for air conditioning and the circuit of the heat pump are connected separately due to different inlet pressures. The heat pump compressor works reversibly and, with appropriate design, can cover the entire climate requirement of the building. The compressor 5 of the normal cooling circuit are connected in parallel and form a compressor unit.

A development of the system, not shown, is that a freezing circuit is connected to the composite.

The compressors 5, 6 compress the refrigerant due to a uniform condensation temperature or a uniform condensation pressure in a common pressure line 17, which connects the compressor unit or the compressor 5, 6 with the heat exchanger of the heat recovery 7. The superheated, present as a hot gas refrigerant is cooled or deprived in the heat exchanger 7 heat recovery and condensed at large dissipating heat output of the heat recovery at least partially. Depending on the transferred heat, the refrigerant is thus partially or completely deprived and / or partially or completely liquefied. The heat transferred to the heat recovery system can be used, for example, to heat a medium within a heating system.

In the condenser 8, which is designed as luftbeaufschlagter heat exchanger, the refrigerant is completely condensed and then stored in the collector 9. If the refrigerant from the heat exchanger 7 of the heat recovery already completely liquefied, the liquid is passed through a bypass (not shown) to the condenser 8 directly into the collector 9.

The decom- missioning ends on reaching the dew line, where the process of condensation begins. In complete condensation or Liquefaction, the refrigerant is at the outlet of each heat exchanger completely as a liquid. If the condensation takes place only partially, the refrigerant exits as a liquid-vapor mixture.

The liquid refrigerant is distributed via the liquid line 18, which connects the collector 9 with the consumers, on the different evaporators 2, 3, 4 and before entering the evaporator 2, 3, 4 by means of expansion valves 11, 13, 15 on the desired pressure level is relaxed. The process of evaporation to provide the cooling capacity of the normal cooling takes place at a different pressure level than the process of evaporation to provide the cooling capacity for air conditioning and heat absorption in the heat pump cycle. In the Fig. 5 Evaporators 2, 3, 4 shown as individual components may also be arranged as composites of a plurality of evaporators. The cooling capacity of the standard cooling system is provided at a temperature level between -5 ° C and -15 ° C and the cooling capacity for air conditioning at a temperature level between 0 ° C and 10 ° C. In the specific application, the evaporator 2 of the normal cooling at an evaporation temperature of -8 ° C and the evaporator 3, 4 for air conditioning and the integrated heat pump circuit operated at an evaporation temperature of +8 ° C. The individual evaporators 2, 3, 4 are connected via solenoid valves 10, 12, 14 switched on and off.

The vaporized, gaseous refrigerant passes back via suction lines 19, 20 to the compressors 5, 6. The cycle is closed.

The refrigerant circuit may additionally be configured with internal heat exchangers as thermal connections between the liquid line 18 and the suction line 19, 20 (not shown). The inner heat exchanger are each in the flow direction on the high pressure side or within the liquid line 18 between the solenoid valve 10, 12, 14 and the expansion valve 11, 13, 15 and within the suction line 19, 20 between the evaporator 2, 3, 4 and Compressor 5, 6 arranged. The heat is transferred from the liquid refrigerant after leaving the collector 9 to the gaseous refrigerant before entering the compressor 5, 6. The refrigerant is on the one hand supercooled on the high pressure side and on the other hand overheated before entering the compressor 5, 6.

The cooling capacities of the evaporators 2, 3, 4 vary depending on the time of day and the season. Depending on the need for heat output within the system of heat recovery, this is covered by the power consumed in the evaporators 2, 3, 4 plus the heat supplied to the refrigerant during the compressor operations. If the required heat output and the sum of the supplied powers deviate from one another such that the heat output within the system of heat recovery can not be covered, the evaporator 4 of the circuit of the heat pump is switched on. The heat absorbed and heat supplied during the compression process are available as additional services to the heat recovery system. The evaporator 4 of the circuit of the heat pump is as well as the condenser 8 subjected to air.

Fig. 6 shows the enclosure 23 of the explosion-proof refrigeration system with the flow diagram of the refrigerant circuit of the refrigeration system 1 with integrated heat pump circuit and integrated condenser-evaporator 16 as a heat exchanger, the condenser 8 of the refrigeration system 1 and the evaporator 4 of the integrated heat pump circuit with respect to in Fig. 5 connected circuit as an integral component connects.

The integrated condenser-evaporator 16 may be formed, for example, as a tube bundle heat exchanger with fins, the fins are advantageously thermally conductively connected both to the tubes of the evaporator 4 of the heat pump circuit and with the tubes of the condenser 8 of the refrigeration system. This will make the surface a Heat transfer during condensation and evaporation increases. The ambient air flows through the interstices of the fins and on the outside of the tubes. The refrigerant flows under evaporation pressure in each case within the tubes in the case of the evaporator 4 of the heat pump circuit and in the case of the condenser 8 under condensation pressure of the refrigeration system 1.

By interleaving the circuits of the integrated condenser-evaporator 16 into each other, also referred to as a condenser with integrated evaporator coil, there are significant advantages in the operation of the refrigeration system. 1

Due to the dual use of the integrated condenser-evaporator 16, the operation is possible even at temperatures around 0 ° C, without an additional system for defrosting the evaporator 4 of the heat pump is needed. By switching off the evaporator 4 and connecting the capacitor 8, with optionally reduced heat output of the system of heat recovery, the defrosting is realized by the heat transfer of the refrigerant during the condensation.

By integrating the evaporator 4 of the heat pump circuit and the condenser 8 of the refrigeration system results in a large area for heat transfer, which in turn advantageously changes the process of heat transfer to lower temperature differences. As a result, the evaporation of the refrigerant in the circulation of the heat pump at a higher temperature and the condensation of the refrigerant at a lower temperature, which leads to a reduction in the supplied compressor power.

Furthermore, the space requirement is reduced by the integration of two heat exchangers in one component.

In Fig. 7 is the enclosure 23 of the explosion-proof refrigeration system with the flow diagram of the refrigerant circuit of the refrigeration system 1 with integrated heat pump circuit and two-part, air-loaded integrated Condenser-evaporator 16a, 16b with associated solenoid valves 14a, 14b and expansion valves 15a, 15b shown. Each part of the two-part condenser-evaporator 16a, 16b, a collector 9a, 9b downstream. The first part of the condenser-evaporator 16a is connected in parallel with the associated header 9a to the second part of the condenser-evaporator 16b with the associated header 9b.

Both sections of the condenser-evaporator 16a, 16b are as capacitors with the respective associated collector 9a, 9b depending on the external conditions or the operating conditions separately, or both parts in parallel, operable.

In winter operation, in which heat is absorbed in the evaporator of the condenser-evaporator 16a, 16b of the heat pump circuit, only part of the condenser-evaporator 16a and the downstream collector 9a is subjected to a refrigerant. The second part of the condenser-evaporator 16b with collector 9b is sucked empty, that is, the condenser of the condenser-evaporator 16b and the collector 9b are not supplied with refrigerant. The lines are closed by valves (not shown) so that the said components are separated from the rest of the refrigerant circuit. Otherwise, the refrigerant could collect within the non-operating components and thus be withdrawn from the refrigerant circuit. The missing amount of refrigerant would have to be compensated by a larger total amount. By separating unused components can advantageously be minimized, the refrigerant quantity or capacity of the system. A smaller amount of refrigerant, especially in installations with flammable refrigerants, significantly reduces the risk of explosions in case of leakage or breakdown.

In summer operation both parts of the condenser-evaporator 16a, 16b and the associated collector 9a, 9b are subjected to refrigerant.

The two-part condenser-evaporator 16a, 16b is operated via the control of valves.

As Fig. 7 Furthermore, the heat transfer circuit for air conditioning, in which the evaporator 3 of the air conditioning is integrated, and the heat transfer circuit of the heat recovery, in which the heat exchanger of the heat recovery is integrated, via bypasses 35, 36 and a three-way valve 34 with its heats and returns associated with each other. With this coupling, it is possible to pressurize the heat carrier circuit for air conditioning both with heated and cooled with heat transfer medium depending on the outdoor or desired operating conditions.

By the circulation of the heated heat exchanger in the heat carrier 7, which flows in the flow direction in the heating mode 38 via the bypass 36 and the three-way valve 34 in the flow of the heat carrier circuit for air conditioning is in the components of the heat carrier circuit for air conditioning, for example in Floor integrated radiator and / or ceiling heat exchanger (not shown), the heat emitted again. The heat exchangers are used for heating. The heat transfer heat released flows back through the bypass 35 to the heat exchanger 7. On the other hand, the components of the heat carrier circuit for air conditioning can be acted upon by the heat carrier cooled in the evaporator 3, which is indicated by the flow direction in the cooling mode 37, so that heat is absorbed in the components. The heat exchangers, for example in the sales rooms, then serve for cooling.

The present invention can be used anywhere where refrigeration systems are needed for cooling and at the same time there is a heat demand. In this case, any conventional, but in particular flammable, refrigerant can be used.

LIST OF REFERENCE SIGNS

1

refrigeration plant

2

Evaporator (normal cooling)

3

Evaporator (climate cooling)

4

Evaporator (heat pump)

5

Compressor / compressor unit (normal cooling)

6

Compressor / compressor unit (air conditioning / heat pump)

7

Heat exchanger (heat recovery)

8th

capacitor

9, 9a, 9b

collector

10, 12, 14, 14a, 14b

solenoid valves

11, 13, 15, 15a, 15b

Expansion device / expansion valve

16, 16a, 16b

integrated condenser-evaporator

17

pressure line

18

liquid line

19, 20

suction

21

pump

22

Connection heat transfer circuit

23

enclosure

24

switch cabinet

25

cabinet door

26

Fan / fan

27

suction

28

Fan, ATEX fan

29

Flow direction air

30

tub

31

gas sensor

32

air duct

33

Tee

34

Three-way valve

35.36

bypass

37

Flow direction in cooling mode

38

Flow direction in heating mode

Claims (15)

Explosion-proof refrigeration system, comprising a housing (23), in which a suction device (27), a gas sensor (31) and a closed refrigerant circuit of a refrigeration system (1) are arranged, wherein - The filled with combustible refrigerant refrigerant circuit of the refrigeration system (1) with the refrigerant-carrying, not explosion-proof components and their connecting elements of the gas-tight housing (23) is enclosed, with only the condenser (8) running air-pressurized heat exchanger outside the housing (23) is arranged - The suction device (27) has an explosion-proof fan (28),
and that a control device is provided such that upon reaching a predetermined concentration of refrigerant gas in the atmosphere of the enclosure (23) - All within the enclosure (23) arranged components of the explosion-proof refrigeration system are disconnected from the power supply and - The operation of the explosion-proof fan (28) is triggered, so that the atmosphere enriched with refrigerant gas within the enclosure (23) is spent outside in the vicinity of the enclosure (23). Explosion-proof refrigeration system according to claim 1, characterized in that all connection points of the refrigerant-carrying lines of the condenser (8) within the housing (23) are arranged. Explosion-proof refrigeration system according to claim 1 or 2, characterized in that in the upper region of an outer wall of the enclosure (23) an additional, not explosion-proof trained Fan (26) is arranged so that not enriched with refrigerant air from the upper portion of the enclosure (23) is sucked. Explosion-proof refrigeration system according to one of claims 1 to 3, characterized in that with the refrigeration system (1) coupled heat transfer fluid circuits are provided with pumps (21), wherein the pumps (21) within the housing (23) are arranged and connections of the heat carrier circuits (22 ) protrude from the gas-tight enclosure (23). Explosion-proof refrigeration system according to one of claims 1 to 4, characterized in that the explosion-proof fan (28) within an air channel (32) is arranged. Explosion-proof refrigeration system according to claim 5, characterized in that the air channel (32) is formed such that a refrigerant-air mixture can be sucked through an open end of the air channel (32) in the lower region of the enclosure (23) and in the air channel (32 ) is brought through the upper part of the enclosure (23) to the outside in the environment of the enclosure (23). Explosion-proof refrigeration system according to claim 5 or 6, characterized in that the air duct (32) in the upper region of the enclosure (23) to the atmosphere of the enclosure (23) open T-piece (33) and the explosion-proof fan (28) within a Air duct (32) in the flow direction of the air after the T-piece (33) is arranged so that air from the upper region of the enclosure (23) through the air passage (32) is sucked through, the air must not be enriched with refrigerant. Explosion-proof refrigeration system according to claim 7, characterized in that the upper opening of the air duct (32) on the T-piece (33) has a controlled ventilation flap, which is closed when the fan (28) and in case of accident. Explosion-proof refrigeration system according to one of claims 1 to 8, characterized in that a switchgear cabinet (24) gas-tight with respect to the enclosure (23) integrated into this and by a cabinet door (25) is formed accessible from the outside. Explosion-proof refrigeration system according to one of claims 1 to 9, characterized in that the enclosure (23) on the bottom by a liquid-tight trough (30) is limited. Explosion-proof refrigeration system according to one of claims 1 to 10, characterized in that the refrigeration system (1) has a closed refrigerant circuit, comprising in the flow direction of the refrigerant: a compressor unit (5, 6), a heat exchanger (7) serving for heat recovery, an air-charged condenser (8) of an integrated condenser-evaporator (16), - a collector (9), - An expansion element (11, 13) and an evaporator (2, 3) and - An additional air-pressurized evaporator (4) with upstream expansion element (15) in the circuit of a refrigeration system (1) integrated heat pump circuit, wherein the evaporator (4) of the heat pump circuit with the capacitor (8) for forming the integrated condenser-evaporator (16) coupled thermally conductive. Explosion-proof refrigeration system according to claim 11, characterized in that the integrated condenser-evaporator (16) of the refrigerant circuit of the refrigeration system (1) is designed as a tube bundle heat exchanger with fins, wherein the fins both the tubes of the evaporator (4) of the heat pump circuit and the tubes of the Capacitor (8) include the refrigeration system, so that the evaporator (4) is formed by switching to the operation as a condenser (8) of the refrigeration system (1) abtaubar. Explosion-proof refrigeration system according to claim 11 or 12, characterized in that the luftbeaufschlagte integrated condenser-evaporator (16) with a downstream collector (9) is formed in two parts and a control of valves is provided so that in each case only a part of the integrated condenser-evaporator ( 16a, 16b) is charged as a condenser with a corresponding collector (9a, 9b) with refrigerant, wherein the other part of the condenser of the condenser-evaporator (16a, 16b) with the associated collector (9a, 9b) is not acted upon by refrigerant and is separated from the rest of the refrigerant circuit by closed valves, or both parts of the capacitor of the integrated condenser-evaporator (16a, 16b) with the associated collectors (9a, 9b) are acted upon simultaneously with refrigerant. Explosion-proof refrigeration system according to one of claims 11 to 13, characterized in that with the refrigeration system (1) coupled heat transfer circuits for air conditioning, cooling and heating are provided, the headers and the returns of the heat carrier circuits for air conditioning and heating via bypasses (35, 36) and the heats are additionally connected to each other via a three-way valve (34), so that the components of the heat carrier circuits for air conditioning and heating with heated or cooled with heat transfer medium can be acted upon. Explosion-proof refrigeration system according to one of claims 11 to 14, characterized in that the evaporator (4) of the integrated heat pump circuit in parallel to an evaporator (2, 3) of the refrigeration system (1) is arranged, wherein the evaporator (4) according to heat demand of the system the heat recovery is switchable formed.

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