Repairing a Compression Faucet
There are two types of faucets found in most homes: compression and non-compression faucets. A compression, or stem and washer, faucet always has separate controls for hot and cold water. A non-compression faucet generally has a single lever that controls the flow of both hot and cold water by means of a ball or cartridge set in the faucet collar.
By design, compression faucets are much more prone to leaks than non-compression faucets. The handle of a compression faucet rotates a threaded stem. When turned off, a washer at the bottom of the stem presses against a valve seat to block the flow of water. Turning the handle in the opposite direction releases the obstruction to the valve, allowing water to flow through the faucet.
A worn washer, deteriorated stem seal or a damaged valve seat can cause a faucet to leak. If the leak comes from the faucet spout, the washer is probably to blame.
Problems with the stem seal (which may be the O-ring) show up as leaks around the handle stem of the faucet. These types of leaks are repaired with the insertion of a new O-ring.
If you replace the faucet washer and still have a drip, or if the washers wear out every few months, the valve seat is probably pitted or scored. The seat is made from soft brass and can be damaged by corrosion. Over tightening the faucet stem in an effort to correct a leak caused by a worn washer can also damage the brass. Valve seats can be ground smooth with a valve seat dressing tool. Some faucets have replaceable valve seats.
Save time by diagnosing the problem first. The location of the leaking water should tell you whether you need a new washer, new stem sealant, or a new or resurfaced valve seat.
Pay attention to the order in which the faucet is taken apart so that after the worn parts are replaced, the unit can be reassembled properly.
What you will need:
Valve seat dressing tool
Rag or masking tape for padding
New stems matching the one you have
Bring the old stems with you to the hardware store to purchase to be sure the parts that will fit. Although the project should only take an hour or so to complete, plan to make the repairs during a time when no other household members will need to use that faucet. Plan to work on your project during the local hardware store’s business hours in case you need additional materials.
Shut off the water supply.
Remove the handles with the puller.
Disassemble the stems from the faucet.
Inspect for a worn washer, o-ring, or valve seat.
Replace the worn parts.
Reassemble the faucet.
Restore the water supply.
Check for leaks or any other problems with the faucet.