Symptoms
- Flow was normal before the repair or shutoff
- Weak or sputtering flow immediately afterward
- Problem is isolated to the faucet that was worked on or nearest the shutoff
- Aerator looks clogged when removed
Likely causes
- CommonDebris dislodged during the repair lodged in the aeratorSediment loosened by the work settles in the first narrow point, usually the aerator.
- CommonDebris lodged inside the cartridgeSmall particles can get trapped in the cartridge's narrow passages.
- PossibleAir trapped in the lineCan cause sputtering that clears with more running time.
- PossibleCartridge or parts installed slightly misaligned during the repairCan partially restrict flow even without any debris.
What to do
- Remove the aerator and run the faucet directly to flush out debris without it re-clogging the screen.
- Run both hot and cold for a minute or two at full flow.
- Clean the aerator screen thoroughly before reinstalling it.
- If flow is still weak with the aerator off, the blockage is likely inside the cartridge or valve body.
- Remove the cartridge again and flush it under running water, checking for trapped debris in its ports.
- Reinstall the cartridge carefully, confirming it's seated fully and in the correct orientation.
- Test flow again once reassembled; it should match pre-repair performance.
Tools and parts
- Adjustable wrench
- Screwdriver
When to call a pro
Call the plumber who did the original repair if flushing debris doesn't restore flow, since a part may need reinstalling correctly.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.