PLATE-TYPE HEAT EXCHANGER, HEAT PUMP DEVICE EQUIPPED WITH PLATE-TYPE HEAT EXCHANGER, AND HEAT PUMP-TYPE HEATING SYSTEM EQUIPPED WITH HEAT PUMP DEVICE

摘要

This plate-type heat exchanger is configured to have a flow passage that is formed by respective spaces between a plurality of stacked heat-transfer plates and that has an inner fin disposed in the flow passage. When the direction of a fluid flowing within the flow passage is defined as a first direction, the direction orthogonal to the first direction is defined as a second direction, and the direction that is orthogonal to both the first and second directions and that is the lamination direction of the heat-transfer plates is defined as a third direction, the inner fin has a lateral surface extending in the third direction and a contact surface that is joined to the heat-transfer plates. The contact surface is formed in a quadrilateral shape as viewed in the third direction. The width W of the contact surface in the second direction is greater than the height H of the lateral surface in the third direction. The contact surface is provided with a first opening in which the length L in the second direction is equal to or greater than the height H of the lateral surface in the third direction.