Abstract: The video signal combining device includes: multiple memory parts each having multiple line memories and respectively acquiring line data of video signals respectively input from multiple input terminals and sequentially writing and storing the acquired line data into the line memories, a reading control part sequentially reading the line data from any one of the line memories in a first-in-first-out manner, and a data output part outputting video combining data in which the line data read by the reading control part is connected. The reading control part reads the line data from determined one of the line memories based on a storage state of the line data in the line memories.

Abstract: An airtightness evaluation device includes a differential pressure gauge to output a pressure difference between two spaces connected to two joints. A system joint for connecting a refrigeration cycle system is connected to one joint of the differential pressure gauge. A pressure vessel is connected to the other joint of the differential pressure gauge. The airtightness evaluation device includes a bypass circuit to connect the system joint and the pressure vessel to each other with bypassing the differential pressure gauge, and a bypass valve to open/close the bypass circuit. The airtightness evaluation device also includes a supply source joint for supplying a pressurization gas to the pressure vessel.

Abstract: A refrigeration cycle apparatus comprises a refrigerant circuit, a water circuit, and a control device. The refrigerant circuit includes a compressor, a four-way valve, a heat exchanger, a fan, a diaphragm mechanism, a water heat exchanger, and an accumulator. Based on a value of a low-pressure sensor or a high-pressure sensor and a water temperature on an outlet side of the water heat exchanger, the refrigeration cycle apparatus determines whether or not there is an abnormality due to dirtiness adhered to a plate inside the water heat exchanger.

Abstract: An airtightness evaluation device includes a differential pressure gauge to output a pressure difference between two spaces connected to two joints. A system joint for connecting a refrigeration cycle system is connected to one joint of the differential pressure gauge. A pressure vessel is connected to the other joint of the differential pressure gauge. The airtightness evaluation device includes a bypass circuit to connect the system joint and the pressure vessel to each other with bypassing the differential pressure gauge, and a bypass valve to open/close the bypass circuit. The airtightness evaluation device also includes a supply source joint for supplying a pressurization gas to the pressure vessel.