Abstract: A heat exchanger includes: a surface with a water-repellent coating. The surface has a surface structure that includes protrusions. Condensed water droplets, each having a droplet diameter that allows a subcooled state to be maintained even under a predetermined freezing condition, combine with one other on the surface and generate an energy. The surface structure uses the energy to remove the combined condensed water droplets from the surface.

Abstract: A heat exchanger includes: a surface with a water-repellent coating. The surface has a surface structure that includes protrusions. Condensed water droplets, each having a droplet diameter that allows a subcooled state to be maintained even under a predetermined freezing condition, combine with one other on the surface and generate an energy. The surface structure uses the energy to remove the combined condensed water droplets from the surface.

Abstract: An electrolysis device is configured such that water flowing into a container from an inlet flows from an upstream side to a downstream side in the container and flows out from an outlet. A first electrode pair is arranged on the upstream side than a second electrode pair. In the electrolysis device, in order to suppress a decrease in current density due to electrolyte concentration in the water in the second electrode pair arranged on the downstream side than the first electrode pair, the current density in the second electrode pair is adjusted.

Abstract: An electrolysis device removes a scale component contained in water that is fed to a water heat exchanger. The electrolysis device has a container having a water inlet port and a water outlet port; a plurality of electrodes provided inside the container; and agitation means for agitating water, between adjacent electrodes, that flows from the water inlet port towards the water outlet port.

Abstract: An electrolysis device includes: a container including a first circulation port functioning as one of an inlet and an outlet for water, and a second circulation port functioning as the other of the inlet and the outlet for water; a plurality of electrode pairs disposed in the container; and a power supply configured to apply a voltage to each of the electrode pairs. Each of the electrode pairs includes a pair of electrode plates. A plurality of the electrode plates are arrayed spaced apart from one another in the thickness direction of the electrode plate. In the electrolysis device, a water channel is formed by the plurality of electrode plates such that water flowing from the inlet into the container reaches the outlet after passing between the pair of electrode plates in each of the electrode pairs.

Abstract: An electrolysis device is configured such that water flowing into a container from an inlet flows from an upstream side to a downstream side in the container and flows out from an outlet. A first electrode pair is arranged on the upstream side than a second electrode pair. In the electrolysis device, in order to suppress a decrease in current density due to electrolyte concentration in the water in the second electrode pair arranged on the downstream side than the first electrode pair, the current density in the second electrode pair is adjusted.

Abstract: A joint includes a joint main body, a sleeve and a nut. The joint main body has a joining hole and an external threaded part. The nut is threaded onto the external threaded part in a threaded state in which the pipe and the sleeve are inserted through the joining hole. The nut joins the pipe to the joining hole via the sleeve. The sleeve is tightly fitted to the pipe and the joining hole by the threading of the nut to induce deformation that expands radially outward. The deformation prevents insertion of the sleeve into the joining hole to a specific position in an unthreaded state in which the pipe and the sleeve have been pulled out from the joining hole.

Abstract: A joint includes a joint main body, a sleeve and a nut. The joint main body has a joining hole and an external threaded part. The nut is threaded onto the external threaded part in a threaded state in which the pipe and the sleeve are inserted through the joining hole. The nut joins the pipe to the joining hole via the sleeve. The sleeve is tightly fitted to the pipe and the joining hole by the threading of the nut to induce deformation that expands radially outward. The deformation prevents insertion of the sleeve into the joining hole to a specific position in an unthreaded state in which the pipe and the sleeve have been pulled out from the joining hole.

Abstract: A joint includes a joint main body, a sleeve and a nut. The joint main body has a joining hole and an external threaded part. The nut is threaded onto the external threaded part in a threaded state in which the pipe and the sleeve are inserted through the joining hole. The nut joins the pipe to the joining hole via the sleeve. The sleeve is tightly fitted to the pipe and the joint main body by the threading of the nut and is cut off through a linking part that links a sleeve main body and a separating part. The sleeve can no longer join the pipe to the joining hole after the nut is removed and the pipe and the sleeve are pulled out from the joining hole.