Centrifugal blower, and indoor unit

A centrifugal blower comprising:

• a drive portion having a rotary shaft that rotates about a rotation axis;
• and
• an impeller that is disposed on one side in an axial direction of the rotation axis with respect to the drive portion and is configured to be rotated forward in a rotation direction around the rotation axis by the drive portion,
• wherein the impeller includes
• a main plate fixed to the rotary shaft,
• a shroud having an annular shape and facing the main plate in the axial direction, and
• a plurality of vane portions connecting the main plate and the shroud,
• the main plate has a hub that covers the drive portion from the one side in the axial direction and from an outside in a radial direction of the rotation axis,
• the hub has a plurality of guide portions protruding outward in the radial direction and arranged in the rotation direction,
• air holes that are open outward in the radial direction are formed in the plurality of guide portions, and
• each outer peripheral surface of the plurality of guide portions has a first peripheral surface portion and a second peripheral surface portion, the first peripheral surface portion being located on a front side in the rotation direction with respect to the air hole and facing outward in the radial direction, the second peripheral surface portion being located on a rear side in the rotation direction with respect to the air hole and facing outward in the radial direction, and
• the second peripheral surface portion extends in the rotation direction and is disposed to be continuous to an opening of the air hole in the rotation direction such that a radial position of the opening of the air hole matches a radial position of the second peripheral surface portion.