PVC GROMMET INSTALLATION GUIDE
Installing the ssi-AFD Disc with a PVC Grommet on metal or plastic pipe
requires care in the mounting of the Grommet and the installation of the
diffuser. The special PVC Grommet shall be installed into the metal or plastic
pipe in accordance with the following procedures:
1) It is recommended that the outside edge of the Grommet be lubricated
with PVC cement.
2) A hole shall be drilled in the pipe to a diameter of 1-1/4" (31.75mm).
It is VERY IMPORTANT to chamfer the hole.
3) The PVC Grommet shall be placed over the opening in the pipe.
4) A rubber mallet shall be used to seat the PVC Grommet into place. Hit
the grommet at with the rubber mallet on the corners, one corner at a time,
until it pops into place.
5) The diffuser shall be inserted into the PVC Grommet and tightened to
seal the PVC Grommet into place in the piping. To retain the diffuser itself
tighten it until there are no threads showing on the diffuser shank, and
then tighten the diffuser one more complete turn. This will fully seat the
PVC Grommet and prevent leaking.
6) For proper performance of the total system it is important to keep the
diffusers level from side to side and to have all diffuser units at approximately
the same elevation along the pipe, normally +/- ½ inch. This provides
superior air distribution and assures optimum performance and oxygen transfer.
7) The pipe itself should be cleaned and flushed of any solids prior to
installation of any diffusers. Cleaning is particularly important after
any drilling of pipe for field installation. Proper cleaning of pipe can
assure long operation without internal fouling of diffuser elements.
