Troubleshooting a Faucet Valve Seat

What You'll Need
Adjustable pipe wrench
Faucet seat wrench
Faucet seat sleeve
Faucet seat grinder
Calcium and scale buildup remover
Petroleum jelly

A faucet valve seat may be the culprit if your kitchen or bathroom tap still drips after you have put in new washers. Problems with faucet valve seats can develop from incorrectly installed washers that allow the faucet stem to grind against the seat, distorting its seal. Mineral deposits from hard water can also result in an imperfect poor fit between the washer and the valve seat. Consult the directions below to troubleshoot problems with your faucet valve seat and stop wasting water from a dripping tap.

Step 1: Determine the Location of the Drip or Leak

If water is escaping from your faucet when it is shut off, you have a drip. If the water escapes around the edge of the faucet when the taps are on and water is flowing, you have a leak. A drip from a non-running faucet can have 2 causes: a poor washer or a defective faucet valve seat. When the washer is replaced and the tap still drips, the seat is most likely the problem.

Step 2: Examine the Faucet Valve Seat

To perform this step, turn off the water supply to the affected faucet. The valve is either under or beside the sink or tub, or you may have to deactivate the water supply to the house from the basement. Remove the faucet valve seat from the faucet with a specialized valve seat wrench. Remove the tap and Insert the wrench till it contacts the valve seat. Turn it anti-clockwise to remove the valve seat, and pull the seat out.

Step 3: Insert a Faucet Seat Sleeve

If you are unable to remove the faucet valve seat, purchase a faucet seat sleeve and insert it firmly over the valve seat so it fits firmly, making a watertight seal.

Step 4: Repair the Faucet Valve Seat

If you were able to release the valve seat, check it for scratches and marks of friction with the washer, or for scale buildup from hard water. To remove scale buildup, soak the valve seat in a solution made to remove lime and scale from metal for about an hour. Scrub it with an old toothbrush to loosen scale in grooves. Rinse the valve seat with clear cold water and reinstall it in the faucet. To repair a scratched valve seat, sand it down with a faucet seat grinder to remove the irregular spots and smooth out the surface. Rinse off the valve seat, apply a thin layer of petroleum jelly and reattach it in the faucet.

Step 5: Replace the Faucet Valve Seat

If your faucet is still dripping after trying these repairs, you need to replace the faucet valve seat. Ensure you get the identical model and size for your faucet at a plumbing or home supply store. If the seat is stuck, you will need to take off the entire faucet assembly. You should replace the entire faucet if its other components are worn or damaged.