Replace whole-house water filter cartridge

Why It Matters

A loaded cartridge stops filtering, restricts pressure throughout the home, and can release captured contaminants back into the water.

Tools

• Filter housing wrench or strap wrench
• Bucket or towels

Materials

• Replacement filter cartridge (same model as existing)
• O-ring lubricant

How to Do It

1. Set a bucket or towels under the filter housing to catch residual water.
2. Shut off the inlet valve supplying the whole-house filter.
3. Depressurize the system by pressing the relief button on the housing, if present, or by opening a nearby faucet until flow stops.
4. Unscrew the housing using a filter housing wrench, turning counterclockwise.
5. Remove the spent cartridge and rinse the inside of the housing.
6. Insert the new cartridge, confirming it matches the existing model's size and type.
7. Apply a thin coat of O-ring lubricant to the O-ring, seat it in its groove, and hand-tighten the housing before snugging it with the wrench.
8. Reopen the inlet valve slowly, check for leaks at the housing seam, and verify that normal pressure is restored at a nearby faucet.

Related Tasks

• Clear sink and shower drain buildup Every 3 months
• Close and reopen the main water shutoff valve Once a year
• Inspect toilets for leaks and worn flappers Once a year