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EP-3967942-B1 - SAFETY SYSTEM AND METHOD FOR CONSTRUCTING AIR CONDITIONING SYSTEM

EP3967942B1EP 3967942 B1EP3967942 B1EP 3967942B1EP-3967942-B1

Inventors

  • STEEN, DAVID
  • CORNELIS, Kevin
  • DEGRANDE, Arne
  • NAKAGAWA, YUUSUKE
  • TANWAR, Harshit

Dates

Publication Date
20260506
Application Date
20210914

Claims (16)

  1. A safety system (700, 700a, 700b, 700c, 700e, 700f) comprising: a first valve unit (200e_1) and a second valve unit (200e_2) which are configured to be used for a heat pump system, each of the first and second valve units having at least one liquid refrigerant pipe portion (311), at least one gas refrigerant pipe portion (330), at least one liquid control valve (364) disposed in the liquid refrigerant pipe portion, a casing (400, 400e) accommodating at least the liquid control valve and having first and second lateral faces (461e, 462e) facing different directions, the first lateral face being formed with a first opening (420), and a refrigerant leakage detector (500) configured to detect an occurrence of a refrigerant leakage in an internal space (401) of the casing, characterized in that : each of the first and second valve units (200e_1, 200e_2) further has at least one gas control valve (365) disposed in the gas refrigerant pipe portion (330) and accommodated in the corresponding casing; the second lateral face of each of the first and second valve units is formed with a second opening (430); the first valve unit and the second valve unit (200e_1, 200e_2) are arranged such that the first lateral face of the first valve unit and the second lateral face of the second valve unit face each other; and the safety system further comprises a connection structure (710, 740a) which is a connecting duct connecting the first opening (420) of the first valve unit (200e_1) and the second opening (430) of the second valve unit (200e_2) and thereby connecting the internal spaces of the casings via the openings, and a discharge structure (720) connected to the connection structure or second opening of the first valve unit, and configured to discharge air from the internal space of the casing in which a refrigerant leakage has occurred.
  2. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 1, wherein in each of the first and second valve units (200e_1, 200e_2), the casing (400, 400e) has a substantially box shape, and the first and second lateral faces (461e, 462e) are opposite faces of the casing.
  3. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 2, wherein: in each of the first and second valve units (200e_1, 200e_2), when viewed from a direction substantially perpendicular to the first and second lateral faces (461e, 462e), the first opening (420) and the second opening (430) at least partially overlap with each other.
  4. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 3, wherein: in each of the first and second valve units (200e_1, 200e_2), the casing (400, 400e) has a bottom face (466e) perpendicular to the first and second lateral faces (461e, 462e), and the casing is configured such that the centers, the ends closer to the bottom face, and/or the ends farther from the bottom face of the first and second openings (420, 430) are at the same distance from the bottom face.
  5. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 4, wherein the first valve unit (200e_1) and the second valve unit (200e_2) are arranged next to each other such that the bottom faces (466e) of the first and second valve units are flush with each other.
  6. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 2 to 5, wherein: in each of the first and second valve units (200e_1, 200e_2), the casing (400, 400e) has a third lateral face (463e) perpendicular to the first and second lateral faces (461e, 462e), and the casing is configured such that the centers, the ends closer to the third lateral face, and/or the ends farther from the third lateral face of the first and second openings (420, 430) are at the same distance from the third lateral face.
  7. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 6, wherein the first valve unit (200e_1) and the second valve unit (200e_2) are arranged next to each other such that the third faces (463e) of the first and second valve units are flush with each other.
  8. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 7, wherein: each of the first and second valve units (200e_1, 200e_2) further has a main liquid refrigerant pipe portion (381e) from which the liquid refrigerant pipe portion (311) branches, and a main gas refrigerant pipe portion (382e) from which the gas refrigerant pipe portion (330) branches; in each of the first and second valve units, an end of the main liquid refrigerant pipe portion and an end of the main gas refrigerant pipe portion protrude from the first lateral face (461e), and the other end of the main liquid refrigerant pipe portion and the other end of the main gas refrigerant pipe portion protrude from the second lateral face (462e); and the safety system further comprises at least one liquid refrigerant connection pipe (161e) connecting the main liquid refrigerant pipe portion of the first valve unit and the main liquid refrigerant pipe portion of the second valve unit (200e_2), and at least one gas refrigerant connection pipe (162e) connecting the main gas refrigerant pipe portion of the first valve unit and the main gas refrigerant pipe portion of the second valve unit.
  9. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 8, wherein: in each of the first and second valve units (200e_1, 200e_2), the casing (400, 400e) has a pipe outlet face (463e) different from the first and second lateral faces (461e, 462e); and an end of the liquid refrigerant pipe portion (311) and an end of the gas refrigerant pipe portion (330) protrude from the pipe outlet face.
  10. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 9, wherein: in each of the first and second valve units (200e_1, 200e_2), the casing (400, 400e) has a drain pan (470e) which is provided with a drain outlet (473e) protruding from an edge of the drain pan; and the casing is configured such that the drain pan is switchable between at least two states in which the drain outlet protrudes towards different directions.
  11. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 10, wherein: the discharge structure (720) includes a shared duct (720a) connected to the connection structure (710) or the second opening (430) of the first valve unit (200e _1), and a ventilator (730) disposed to the shared duct; and the safety system (700e) further comprises a controller (600) configured to control the ventilator to start operating when a refrigerant leakage in any of the first and second valve units (200e_1, 200e_2) has occurred.
  12. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to claim 11, further comprising: a damper (440) configured to block air to pass through a terminal first opening when the damper is closed, and allow air to pass through the terminal first opening when the damper is open, the terminal first opening being the first opening (420) of the second valve unit (200e_2), wherein the shared duct (720) is connected to the second opening (430) of the first valve unit (200e_1), and the controller (600) is configured to control the damper to open when the ventilator operates due to the occurrence of the refrigerant leakage in any of the first and second valve units (200e_1, 200e_2).
  13. The safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 11, further comprising: a damper unit (440e) configured to be attachable to the first opening (420) of any of the first and second valve units (200e_1, 200e_2), and in a state where the damper unit is attached to the first opening, block air to pass through the first opening when the damper (440) is closed, and allow air to pass through the first opening when the damper is open.
  14. A method for constructing an air conditioning system (100f), the air conditioning system comprising: the safety system (700, 700a, 700b, 700c, 700e, 700f) according to any one of claims 1 to 13; a heatsource-side unit (110) including a compressor and a heatsource-side heat exchanger; a plurality of utilization-side units (120) each including a utilization-side heat exchanger; a liquid refrigerant piping extending between the heatsource-side unit and the utilization-side units, and including the liquid refrigerant pipe portions (311); a gas refrigerant piping extending between the heatsource-side unit and the utilization-side units, and including the gas refrigerant pipe portions (330); and an expansion mechanism disposed in the liquid refrigerant piping, the method comprising: installing the first and second valve units (200, 200d, 200e, 200f), the connection structure (740a), the discharge structure (720a), and the utilization-side units in the same floor of a building; and connecting the first and second valve units by the connection structure, and connecting the discharge structure to the connection structure or one of the casings (400, 400e).
  15. The method for constructing the air conditioning system (100f) according to claim 14, wherein the installing includes: installing the utilization-side units (120) in a first space which is to be air-conditioned by the utilization-side units; and installing the first and second valve units (200, 200d, 200e, 200f), the connection structure (740a), and the discharge structure (720a) of the safety system (700f) in a second space which is adjacent to the first space.
  16. The method for constructing the air conditioning system (100f) according to claim 14, wherein the installing includes: installing the utilization-side units (120), the first and second valve units (200, 200d, 200e, 200f), the connection structure (740a), and the discharge structure (720a) in the same space which is to be air-conditioned by the utilization-side units.

Description

Field of Invention The present invention relates to a safety system for a heat pump system and a method for constructing an air conditioning system including the safety system. Background In heat pump systems such as an air conditioning system for a plurality of target spaces, each of a liquid refrigerant pipe and a gas refrigerant pipe of a heat pump circuit is branched into a plurality of sub piping systems. The branched sub pipes in the sub piping systems are often provided with valves to zone the sub piping systems. Meanwhile, each valve used in the heat pump system tends to become a leakage point of refrigerant, and thus needs to be regularly checked and repaired as necessary. Hence, for the convenience of monitoring and maintenance, it is common to design a piping of a heat pump system so as to arrange a plurality of valves in one place. For example, EP 3 091 314 A1 proposes to integrate a plurality of valves of the refrigerant sub pipes within a single casing to form a valve unit. Thereby, it is possible to not only ease the burden of monitoring/maintenance but also prevent refrigerant leaked at any valve from spreading to the surrounding area. However, it is sometimes difficult to accommodate all the valves into a single casing, due to the number of the valves, arrangement of the piping, a spatial limitation, or the like. If the valves are separated into a plurality of separate casings, it is burdensome and takes time to open each of the casings to check whether a refrigerant leakage has occurred at any valve. Moreover, if a refrigerant leakage has occurred at any valve, the internal space of the casing accommodating the valve would have already been permeated with a significant amount of leaked refrigerant when the monitoring/maintenance person arrives to open the casing. For instance, some refrigerants used are flammable or slightly flammable. Thus, opening such a casing is undesirable from safety perspective. Furthermore, the spaces where the valve units are to be disposed tend to be limited. In particular, when the valve units are installed in a ceiling space of a building, it is desirable to reduce height range of an arrangement space of the valve units as much as possible. In addition, it is also beneficial to reduce the area of the arrangement space. EP 3 282 203 A1 discloses a safety system comprising: a first valve unit and a second valve unit which are configured to be used for a heat pump system, each of the first and second valve units having at least one liquid refrigerant pipe portion, at least one gas refrigerant pipe portion, at least one liquid control valve disposed in the liquid refrigerant pipe portion, a casing accommodating at least the liquid control valve and having first and second lateral faces facing different directions, the first lateral face being formed with a first opening, and a refrigerant leakage detector configured to detect an occurrence of a refrigerant leakage in an internal space of the casing. EP 3 091 314 A1 discloses an aggregated channel switching unit configured to switch flow of refrigerant. Summary The object of the present invention is to provide a safety system and a method for constructing an air conditioning system that can improve safety of a heat pump system regarding refrigerant leakage from valves even in a case where a plurality of valve units should be arranged in a limited space. The object above is achieved by the safety system defined by the appended claim 1 and the method for constructing the same as defined by the appended claim 14. Further advantageous effects can be obtained by the preferred embodiments defined by appended dependent claims. A first aspect of the present invention provides a safety system comprising: a plurality of valve units used for a heat pump system, each of the valve units having at least one liquid refrigerant pipe portion, at least one gas refrigerant pipe portion, at least one liquid control valve disposed in the liquid refrigerant pipe portion, at least one gas control valve disposed in the gas refrigerant pipe portion, a casing accommodating at least the liquid control valve and the gas control valve and formed with at least two openings, and a refrigerant leakage detector configured to detect an occurrence of a refrigerant leakage in an internal space of the casing; a connection structure connecting the internal spaces of the casings via the openings; and a discharge structure connected to the connection structure or one of the casings, and configured to discharge air from the internal space of the casing in which a refrigerant leakage has occurred, wherein the casing of each valve unit has first and second lateral faces facing different directions, and in each of the valve units, a first opening as one of the openings is formed in the first lateral face and a second opening as another one of the openings is formed in the second lateral face. With the above configuration, even if a refrigerant leakage has occ