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EP-4596994-B1 - REFRIGERANT SYSTEM AND REFRIGERANT MODULE

EP4596994B1EP 4596994 B1EP4596994 B1EP 4596994B1EP-4596994-B1

Inventors

  • BRÜCKNER, Stefan
  • RÜHROLD, Ian
  • SCHMITT, GUNNAR
  • WINTER, RAPHAEL

Dates

Publication Date
20260513
Application Date
20221205

Claims (13)

  1. Refrigerant system with - a refrigerating circuit (12), which has two heat exchangers, to be specific an evaporator (70) and a condenser (68), and also a compressor as well as an expansion valve and in which a refrigerant circulates during operation, wherein at least one hydraulic circuit (64, 66), in which a carrier medium is circulated during operation, is connected to the refrigerating circuit (12) in the installed state, - a system housing (4), which in the installed state is installed in an installation room (26) and in which at least a number of components of the refrigerating circuit (12) and further components, such as hydraulic or electrical components, are arranged, wherein a sealed control housing (14), in which the components comprising the compressor, the expansion valve and at least one of the heat exchangers of the refrigerating circuit (12) are arranged, is arranged inside the system housing (4), and wherein a discharge line (16), which is intended for discharging gas from the control housing (14) and is in flow connection with an external area (28) outside the installation room (26), is connected to the control housing (14), wherein a fan (30) is arranged in the discharge line (16), characterized in that a device for detecting a leakage in the refrigerating circuit (12) is provided and comprises an evaluation unit (76), which is designed in such a way that it infers a leakage within the refrigerating circuit (12) on the basis of at least one characteristic value of the fan (30).
  2. Refrigerant system according to the preceding claim, characterized in that one of the two heat exchangers is designed as an air/refrigerant heat exchanger and is arranged in an air duct (62), wherein the discharge line (16) opens out into the air duct (62), wherein the air duct (62) runs in particular inside the system housing (4) and is preferably connected via interfaces (22) to duct sections (86) leading into the external area (28).
  3. Refrigerant system according to the preceding claim, characterized in that the discharge line (16) provides a permanently open flow connection to the external area (28), so that escaping refrigerant can automatically flow into the external area (28), wherein the open flow connection is preferably free from internal fittings.
  4. Refrigerant system according to one of the preceding claims, characterized in that the control housing (14) has no supply-air opening.
  5. Refrigerant system according to one of the preceding claims, characterized in that the at least one heat exchanger is connected via a connection line (84), running inside the control housing (14), to the at least one hydraulic circuit (64, 66), wherein a gas separator (40), which is intended for the direct degassing of a carrier medium conducted in the hydraulic circuit (64, 66) into the control housing (14), is attached to the connection line (84).
  6. Refrigerant system according to one of the preceding claims, characterized in that on the hydraulic circuit (64, 66) outside the control housing (14) a device, to be specific a safety valve (48) and/or a buffer storage tank (58), is respectively connected to a venting line (36), wherein the venting line (36) opens out at least indirectly into the external area (28) and, in the case of an air/water refrigerant system (2), opens out into an air duct (62), in which an air/refrigerant heat exchanger is arranged.
  7. Refrigerant system according to one of the preceding claims, characterized in that arranged in the hydraulic circuit (64, 66) is a shut-off device (78), in particular a shut-off or sealing valve, which in the event of a pressure increase and/or an increase in the volumetric flow beyond a limit value shuts off the hydraulic circuit (64, 66), in particular in such a way that it is no longer in flow connection with the at least one heat exchanger, wherein preferably a heat-sink-side or heat-source-side subregion of the hydraulic circuit (64, 66) is hydraulically disconnected from a refrigerating-circuit-side subregion of the hydraulic circuit (64, 66).
  8. Refrigerant system according to the preceding claim, characterized in that the shut-off device (78) is a passive shut-off element which automatically shuts off the hydraulic circuit (64, 66) when the limit value is exceeded and preferably also releases it again when the limit value is no longer exceeded.
  9. Refrigerant system according to one of the preceding claims, characterized in that an internal piece (16A) of the discharge line (16) and at least one connecting line (20) for the at least one hydraulic circuit (64, 66) are connected to the control housing (14) and the internal piece (16A) and the at least one connecting line are led to a respective interface (22) of the system housing (4), via which an external piece (16B) of the discharge line (16) and at least parts of the at least one hydraulic circuit (64, 66) can be coupled, wherein, in a preferred configuration, coupling elements (72) intended for connecting, in particular reversibly, to the internal piece (16A) and/or to the at least one connecting line (20), and also preferably to at least one of the further components arranged in the system housing (4), are arranged on the control housing (14).
  10. Refrigerant system according to one of the preceding claims, characterized in that the system housing (4) is designed in the manner of a module cabinet and the control housing (14) is arranged inside a refrigerant module (6), wherein preferably a storage module (8) with a service-water storage tank (10) is additionally provided and the refrigerant module (6) and the storage module (8) are in particular arranged one on top of the other.
  11. Refrigerant system according to one of the preceding claims, characterized in that at least one of the following characteristic values of the fan (30) is evaluated: - fan characteristic curve or current operating point, - rotational speed, in particular in a state when the fan is not actively operated, - electrical current or power consumption, - vibration.
  12. Refrigerant system according to the preceding claim, characterized in that a leakage rate is derived from the characteristic value.
  13. Refrigerant system according to one of the preceding claims, characterized in that a device for detecting a leakage in the refrigerating circuit (12) is provided and a gas sensor (34), in particular a CO 2 sensor, or a pressure sensor is arranged in the control housing (14) as the device for detecting the leakage.

Description

The invention relates to a refrigerant system, which is designed in particular for indoor installation, i.e., as a so-called indoor system. Such a refrigerant system generally comprises a refrigeration circuit which includes two heat exchangers, namely an evaporator and a condenser, as well as a compressor and an expansion valve. A refrigerant flows in the refrigeration circuit during operation. During the service life of refrigerant systems, refrigerant leaks can occur for a variety of reasons. In the case of indoor systems, these leaks can directly affect the installation room. Depending on the installation and use of the refrigerant system, several rooms or even the entire building may be affected by escaping refrigerant from leaks. The escaping refrigerant usually escapes in gaseous or sometimes liquid form, which then re-gasifies. This can lead to concentrations that are harmful or toxic to living beings. Furthermore, the decomposition of some refrigerant gases on hot surfaces can produce toxic decomposition products. Additionally, the use of highly or highly flammable refrigerants poses a risk of deflagration, explosion, or fire if flammable mixtures interact with ignition sources simultaneously. From the DE 10 2016 112 851 A1 A refrigerant system is to be removed in which the refrigeration circuit is arranged within a housing in which a negative pressure relative to the environment is maintained. This is intended to prevent the escape of refrigerant gas into the environment. According to the DE 20 2016 103 305 U1 The refrigeration circuit is also housed in a casing containing a pressure sensor that monitors the internal pressure. A pressure increase is identified as a leak in the refrigeration circuit, and an exhaust system draws in outside air to the interior of the casing. The air, now enriched with refrigerant, is then expelled to the outside, into the surrounding environment. From the DE 10 2018 113 332 A1 A flushing of the housing of a refrigeration circuit is also provided, with an outlet leading to the environment outside the building. Out of EP 3 792 572 A1 A safety flushing device for a brine-to-water heat pump can be removed, which has a capsule housing in which the components of the refrigeration circuit are arranged and to which an air duct leading to the outside and/or an internal outlet via an adsorber for refrigerant occurring in the event of a leak is attached. FR 2 827 948 A1 also describes a heat pump with a housing to which an air duct leading to the outside is connected. EP 3 199 883 A1 shows a heat pump with an outdoor unit installed outdoors. EP 3 767 186 A1 Figure 1 shows a safety device for an outdoor unit of a heat pump, wherein the refrigeration circuit is arranged in the outdoor unit and the outdoor unit is connected to the building via hydraulic lines, the hydraulic lines running outdoors having shut-off valves and a vent. Based on this, the invention aims to provide a refrigerant system and a refrigerant module that are easy to install and at the same time offer a high level of protection against refrigerant leakage and against This ensures the prevention of an accumulation of critical refrigerant concentrations in the installation room. The problem is solved according to the invention by a refrigerant system specifically for indoor installation, comprising a refrigeration circuit with the features of claim 1. The refrigeration circuit has two heat exchangers, namely an evaporator and a condenser, as well as a compressor and an expansion valve. A refrigerant circulates in the refrigeration circuit during operation. In the installed state, at least one hydraulic circuit is connected to the refrigeration circuit, in which a liquid transfer medium, in particular a liquid heat transfer fluid, typically water, optionally with additives, is circulated. The refrigerant system generally has a housing in which at least some, and preferably all, components of the refrigeration circuit, as well as other components, are arranged. The other components are hydraulic or electrical components required and used for the operation of the refrigerant system. These include, for example, circulation pumps, piping, an expansion vessel, valves, and a storage tank, such as a domestic hot water tank. With regard to the electrical components, this primarily includes a system control unit with an operator terminal. Furthermore, a sealed control housing is arranged within the system casing, containing the compressor, expansion valve, and at least one, and preferably both, heat exchangers of the refrigerant circuit. The control housing encloses a control volume that serves to collect refrigerant that has escaped from the refrigerant circuit. A drain for the controlled removal of gas from the control volume is also connected to the control housing. When installed, the system casing is located in a room where the refrigerant system is housed. The drain is connected to an external environment outside th