All Kestrels feature a patented user-replaceable impeller assembly.

The impeller assembly is sold as a replacement impeller for all models in the Kestrel hand-held instrument range. It can also be used in other flow measurement applications.

The light weight impeller is mounted on a precision axle with low-friction Zytel® bearings to provide accurate flow measurements even at low wind speeds. A magnet is mounted on the axle, so the impeller's rotation can be easily sensed.

The impeller housing is designed so no adjustment of the bearings is required. During the manufacturing process each assembly is individually tested in a wind tunnel. This ensures that when a new impeller assembly is installed in a Kestrel instrument the accuracy of the instrument is restored to within specification.

Step 1. Using your thumbs press FIRMLY on the impeller module to remove the entire unit.
Step 2. Press only the sides of the new impeller when installing to avoid damaging the precision hub bearing.
Step 3. Insert the impeller so that the side that has a small triangle (close to the perimeter) faces the front of the Kestrel when installed.
Step 4. Orient one "arm" straight up (fig.1 & fig.2).
Step 5. The impeller can be pushed in from either side.

Compatible with all Kestrel meters