Abstract: Heat pump equipment comprising at least three heat exchangers, one of which is intended to be located in an enclosed region and the other two of which are intended to be located outside the enclosed region. Each heat exchanger has a delta connection end connected in heat-exchange fluid communication with a delta arrangement. The delta connection end of each heat exchanger is connected to both of the delta connection ends of the other two heat exchangers via the delta arrangement. There are three fluid-expansion devices, one between the two connections of each pair of adjacent connections of the heat exchangers to the delta arrangement. The present invention extends to heat pump equipment comprising at least three heat exchangers connected in a heat-exchange fluid circuit, one of which heat exchangers is intended to be located in an enclosed region and another of which is intended to be located outside the enclosed region.

Abstract: Heat pump equipment comprising at least three heat exchangers, one of which is intended to be located in an enclosed region and the other two of which are intended to be located outside the enclosed region. Each heat exchanger has a delta connection end connected in heat-exchange fluid communication with a delta arrangement. The delta connection end of each heat exchanger is connected to both of the delta connection ends of the other two heat exchangers via the delta arrangement. There are three fluid-expansion devices, one between the two connections of each pair of adjacent connections of the heat exchangers to the delta arrangement.

Abstract: Heat exchange equipment comprising a compressor which is connected to an indoor heat exchanger and also to two outdoor heat exchangers, and 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. Pressure lowering means are provided between the two outdoor heat exchangers.

Abstract: A dynamic background subtraction circuit is disclosed which improves the display resolution of radiation energy spectra, such as X-ray energy spectra in an X-ray energy spectrometer. In this circuit, the number of radiation events (counts) occurring at a reference or background energy level is subtracted from the number of radiation events (counts) occurring at a second energy level under study. The output of this circuit is a real-time (dynamic) approximation of the count rate at the energy level under study, but with resolution improved by subtraction of the background counts.