# US 2018/0321131 A1 · Environmental test chamber with uniform airflow > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0321131 A1 - Document ID: US20180321131A1 - Status: Published application - Kind: A1 - Application number: 15/549,504 - Filed: 2016-09-19 - Published: 2018-11-08 - Earliest claimed: 2016-05-12 - Assignees: Weiss Technik North America, Inc. - Applicants: Weiss Technik North America, Inc. - Inventors: Paul C. Supp; Sean S. McKendry; Benjamin J. DeJager - Web page: https://patentgrep.com/patent/US20180321131A1 ## CPC - G01N 17/002: {Test chambers} - F25B 39/02: Evaporators - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F25B 39/028: {having distributing means} - F25B 41/00: Fluid-circulation arrangements - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS ## Abstract An environmental test chamber, and method of testing a response of a unit-under-test to treated air, includes a housing having an enclosing wall defining a test bay with an access opening in the wall providing access to the test bay and a closure selectively covering the opening. An airflow plenum supplies treated air to the test bay. An air treatment system treating air flowing through the plenum. A control operates the air treatment system to flow treated air through the plenum in two selective modes. The air treatment system flows treated air in a first flow direction through the test bay in one of the modes and flows air in a second flow direction through the test bay in a second of the modes. The first and second flow directions are different from each other. ## Claims ### Claim 1 An environmental test chamber, comprising: a housing having an enclosing wall defining a test bay with an access opening in said wall providing access to said test bay and a closure selectively covering said opening; an airflow plenum supplying treated air to said test bay; an air treatment system treating air flowing through said plenum; and a control, said control operating said air treatment system to flow treated air through said plenum in two selective modes, wherein said air treatment system flows treated air in a first flow direction through said test bay in one of the modes and flows air in a second flow direction through said test bay in a second of the modes, wherein said first and second flow directions being different from each other wherein the control is adapted to receive a selection of the mode of operating of the air treatment system based at least in part upon orientation in the test bay of a unit-under-test. ### Claim 2 (depends on 1) The environmental test chamber as claimed in claim 1 wherein the first and second flow directions being generally opposite from each other. ### Claim 3 (depends on 1) The environmental test chamber as claimed in claim 1 wherein said air treatment system includes at least one fan, said at least one fan being reversible between the first and second flow directions. ### Claim 4 (depends on 3) The environmental test chamber as claimed in claim 3 wherein said at least one fan comprises a plurality of fans. ### Claim 5 (depends on 3) The environmental test chamber as claimed in claim 3 wherein said at least one fan comprises a reversible motor and a plurality of bi-directional axial flow blades. ### Claim 6 (depends on 3) The environmental test chamber as claimed in claim 3 wherein said at least one fan comprises a variable speed motor in order to provide variable speed of treated air. ### Claim 7 (depends on 1) The environmental test chamber as claimed in claim 1 wherein said plenum extends generally from top to bottom of said test bay and has air openings at one end of the test bay and other air openings at an opposite end of the test bay. ### Claim 8 (depends on 7) The environmental test chamber as claimed in claim 7 wherein said air openings are adjacent said access opening and said other air openings are opposite said access opening. ### Claim 9 (depends on 7) The environmental test chamber as claimed in claim 7 wherein said air openings comprise a grill and said other air openings comprise another grill. ### Claim 10 An environmental test chamber, comprising: a housing having an enclosing wall defining a test bay with an access opening in said wall providing access to said test bay and a closure selectively covering said opening; an airflow plenum supplying treated air to said test bay; an air treatment system treating air flowing through said plenum; a control, said control operating said air treatment system to flow treated air through said plenum in two selective modes, wherein said air treatment system flows treated air in a first flow direction through said test bay in one of the modes and flows air in a second flow direction through said test bay in a second of the modes, wherein said first and second flow directions being different from each other; and wherein said air treatment system comprises a refrigeration system having an evaporator coil and a fluid circuit for routing refrigerant through said evaporator coil, wherein said fluid circuit includes a first fluid circuit portion that is configured to optimize cooling of air flowing one direction through said evaporator coil and a second fluid circuit portion that is configured to optimize cooling of air flowing a second opposite direction through said evaporator coil. ### Claim 11 (depends on 10) The environmental test chamber as claimed in claim 10 wherein said first fluid circuit portion is configured to flow refrigerant in a direction through said evaporator coil and said second fluid circuit portion is configured to flow refrigerant in a second opposite direction through said evaporator coil. ### Claim 12 (depends on 10) The environmental test chamber as claimed in claim 10 wherein said first fluid circuit portion alternates with said second fluid circuit portion horizontally and vertically in said evaporator coil. ### Claim 13 (depends on 10) The environmental test chamber as claimed in claim 10 wherein said evaporator coil comprises at least one evaporator coil in said plenum on a side of said at least one fan. ### Claim 14 A method of testing a response of a unit-under-test to treated air in an environmental test chamber, comprising: the environmental test chamber having a housing, an airflow plenum and an air treatment system, said housing having an enclosing wall defining a test bay with an access opening in said wall providing access to said test bay and a closure selectively covering said opening, said airflow plenum supplying treated air to said test bay and said air treatment system treating air flowing through said plenum; and operating said air treatment system to flow treated air through said plenum in two selective modes, wherein said air treatment system flows treated air in a first flow direction through the unit-under-test in one of said modes and flows air in a second flow direction through the unit-under-test in a second of said modes, wherein said first and second flow directions being different from each other, including selecting the mode of operating the air treatment system based at least in part upon orientation in the test bay of the unit-under-test. ### Claim 15 (depends on 14) The method of testing as claimed in claim 14 wherein the unit-under-test has a cooling fan and including selecting the one of said selective modes according to the orientation in the test bay of the cooling fan of the unit-under-test. ### Claim 16 (depends on 14) The method of testing as claimed in claim 14 wherein supplying treated air comprises supplying treated air below a rate that would force treated air through the unit-under-test. ### Claim 17 (depends on 16) The method of testing as claimed in claim 16 wherein said air treatment system provides treated air at selectable flow rates. ### Claim 18 A refrigeration system for use in an environmental test chamber having a housing with an enclosing wall defining a test bay with an access opening in said wall providing access to said test bay and a closure selectively covering said opening, an airflow plenum supplying treated air to said test bay, an air treatment system treating air flowing through said plenum and a control, said control operating said air treatment system to flow treated air through said plenum in two selective modes, wherein said air treatment system flows treated air in a first flow direction through said test bay in one of the modes and flows air in a second flow direction through said test bay in a second of the modes, wherein said first and second flow directions being different from each other, wherein said air treatment system includes a refrigeration system, said refrigeration system comprising: an evaporator coil and a fluid circuit for routing refrigerant through said evaporator coil, wherein said fluid circuit includes a first fluid circuit portion that is configured to optimize cooling of air flowing one direction through said evaporator coil and a second fluid circuit portion that is configured to optimize cooling of air flowing a second opposite direction through said evaporator coil. ### Claim 19 (depends on 18) The refrigeration system as claimed in claim 18 wherein said first fluid circuit portion is configured to flow refrigerant in a direction through said evaporator coil and said second fluid circuit portion is configured to flow refrigerant in a second opposite direction through said evaporator coil. ### Claim 20 (depends on 18) The refrigeration system as claimed in claim 18 wherein said first fluid circuit portion alternates with said second fluid circuit portion horizontally and vertically in said evaporator coil. ### Claim 21 (depends on 18) The refrigeration system as claimed in claim 18 wherein said evaporator coil comprises at least one evaporator coil in said plenum on a side of said at least one fan.