I ordered the undersink FXULC filter and received the Culligan D-30A as a replacement. The FXULC has a small hole in each end of the indent of the filter but the D-30A has only one small hole in the top indent of the filter. Is this a functional difference or does it not matter?
The small hole is a flow restrictor that slows the water flow to allow more contact time with the filter. This reduces water flow, but increases filtration.
The Culligan D-30A should be installed with the small hole facing up in the housing to use the flow restrictor.
These filters will function equivalently.
Thanks for the info, Alex and for taking the time to reply.
Originally Posted by Alex