The Home Master whole-house water filter setup that Came With The House™ has a sediment filter with a 6 to 12 months lifetime and a “catalytic carbon” filter that need replacing every 95000 gallons. Poughkeepsie City water isn’t particularly challenging and our average use suggests a three-year cycle for the carbon filter, so changing them every 18 months seems reasonable.
The filter headers have fingers to center the cartridges, which works well with the relentlessly cylindrical sediment filter. The header’s outlet orifice produces the indented ring around the central hole:
The water flows downward around the outside of the filter and upward through the central hole.
The carbon filter is about the same diameter, but has a smaller diameter around the outlet that apparently doesn’t engage the centering fingers:
The white crud on the black rubber seal is another example of Nisley’s First Rule of Potable Water Plumbing:
Never ever look inside the pipes supplying your drinking water.
Having seen this happen twice, despite my best efforts to keep the filter housing vertical while tightening its screw threads in the header, I laser-cut four acrylic blocks to hold the filter in the center of the housing:
They’re 13 mm wide, 15 mm tall, and 6 mm thick, but the next time around they should be taller to help keep them vertical while sliding them into place.
We’ll know how well they worked in about 18 months.
The Smell of Molten Projects in the Morning 
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