Patent ID: 6276158
Filing Date: 2001-08-21
Classification: F25B

Abstract:
Heat exchange equipment comprising a heat exchanger intended to be in contact with air for indoor circulation, two heat exchangers both intended to be in contact with outdoor air, and a compressor connected to the indoor heat exchanger and to both outdoor heat exchangers so that a heat exchange fluid can flow between the compressor and the heat exchangers, the equipment further comprising flow-direction changing means to change the direction of flow in the heat exchangers whereby each of the outdoor heat exchangers can be defrosted whilst the other continues to remove heat from its surroundings, in which the equipment further comprises pressure lowering means between the two outdoor heat exchangers, and in which the fluid-direction changing means are provided between the compressor and the heat exchangers to enable a first direction of flow of the heat exchange fluid, wherein the latter passes from the indoor heat exchanger to one of the outdoor heat exchangers to defrost it, and thence to the other outdoor heat exchanger via the said pressure lowering means before it is returned to the compressor, so that the said other outdoor heat exchanger removes heat from its surroundings, and a second direction of flow of the heat exchange fluid, wherein the latter passes from the indoor heat exchanger to the said other outdoor heat exchanger to defrost it, and thence to the said one of the outdoor heat exchangers via the said pressure lowering means, before it is returned to the compressor, so that the said one of the outdoor heat exchangers removes heat from its surroundings, and in which the equipment further comprises control means connected so as to be able to issue control signals to the fluid-direction changing means to cause the latter to change the flow of the heat exchange fluid from one of the said first and second directions to the other, and further wherein the pressure lowering means comprises one pressure lowering device which serves both the outdoor heat exchangers, the flow direction changing means being such as to ensure that, for both the said first and second directions of flow of the heat exchange fluid, the latter passes through the said pressure lowering device in the same direction.