Air conditioning method and device

A method for conditioning air in a test space of a test chamber which serves to receive test material and which can be sealed against an environment and is temperature-insulated, a temperature in a temperature range of −20° C. to +180° C. being established within the test space by a cooling device of a temperature control device of the test chamber, the cooling device comprising a cooling circuit with a refrigerant, a heat exchanger, a compressor, a condenser and an expansion element, an internal heat exchanger of the cooling circuit connected to a high-pressure side of the cooling circuit upstream of the expansion element and downstream of the condenser and to a low-pressure side of the cooling circuit upstream of the compressor and downstream of the heat exchanger being used to cool the refrigerant of the high-pressure side,

• wherein
• a zeotropic refrigerant is used as the refrigerant, cooling of the refrigerant of the high-pressure side by means of the internal heat exchanger being used to lower an evaporation temperature at the expansion element and wherein a refrigerant mixture composed of a mass fraction of carbon dioxide (CO2) of 30 to 50 mass percent and a mass fraction of at least one other component is used as the refrigerant, the other component being pentafluoroethane (C2HF5) and/or difluoromethane (CH2F2).

A method for conditioning air in a test space of a test chamber which serves to receive test material and which can be sealed against an environment and is temperature-insulated, a temperature in a temperature range of −20° C. to +180° C. being established within the test space by a cooling device of a temperature control device of the test chamber, the cooling device comprising a cooling circuit with a refrigerant, a heat exchanger, a compressor, a condenser and an expansion element, an internal heat exchanger of the cooling circuit connected to a high-pressure side of the cooling circuit upstream of the expansion element and downstream of the condenser and to a low-pressure side of the cooling circuit upstream of the compressor and downstream of the heat exchanger being used to cool the refrigerant of the high-pressure side,

• wherein
• a zeotropic refrigerant is used as the refrigerant, cooling of the refrigerant of the high-pressure side by means of the internal heat exchanger being used to lower an evaporation temperature at the expansion element and wherein the cooling device is operated exclusively below the critical point of the refrigerant.

A test chamber for conditioning air, the test chamber comprising a test space which serves to receive test material and which can be sealed against an environment and is temperature-insulated, and a temperature control device for controlling the temperature of the test space, a temperature in a temperature range of −20° C. to +180° C. being establishable within the test space by the temperature control device, the temperature control device having a cooling device comprising a cooling circuit with a refrigerant, a heat exchanger, a compressor, a condenser and an expansion element, the cooling circuit having an internal heat exchanger, the internal heat exchanger being connected to a high-pressure side of the cooling circuit upstream of the expansion element and downstream of the condenser and to a low-pressure side of the cooling circuit upstream of the compressor and downstream of the heat exchanger,

• wherein
• the refrigerant is a zeotropic refrigerant, the refrigerant of the high-pressure side being coolable by the refrigerant of the low-pressure side at constant suction pressure on the low-pressure side by means of the internal heat exchanger and wherein a dew point temperature of the refrigerant is greater than a minimum temperature of the temperature range.