How to Fix a Leaking Frost-Proof Faucet

Knoji reviews products and up-and-coming brands we think you'll love. In certain cases, we may receive a commission from brands mentioned in our guides. Learn more.
How to perform simple repairs to fix a leaking frost-proof faucet.

Frost-Proof faucets, also known as sillcocks, are becoming more popular with homeowners as they eliminate the need for draining and shutting off the water supply to exterior hose bibbs in parts of the country that experience freezing temperatures. That being said, frost-proof faucets are not maintenance-free and a leaking frost-proof faucet can waste a lot of water. Fortunately the repairs are similar to standard faucets where the washer assembly or packing nut is the common culprit, but the frost-proof faucet does have the additional component of a vacuum breaker. You should not have to call a plumber for this repair as long as you can isolate the frost-proof faucet with a shut off valve in the line.

The big problem with not repairing a leak with any type of outdoor faucet is that the water will collect near the foundation and may aggravate damp basements. If the water leaks during the winter, the water may freeze and can damage the faucet.

Depending on the type of frost-proof faucet you have, the body of the faucet can be 6 to 30 inches long. This allows the faucet to be controlled from the exterior but the wet side of the valve is inside the basement and protected from freezing temperatures.

Make sure that your frost-proof faucet is pitched down so that the water inside the valve can drain out.

Tools and Materials

4-in-1 screwdriver

Adjustable wrench

Pump pliers

Washer Repair Kit

Vacuum Breaker Repair Kit


1. Checking the Retaining nut

If the faucet is leaking around the stem of the handle you might get away with just tightening the nut under the handle. Remove the handle by removing the screw in the center. Hold onto the body of the faucet with your pump pliers and then carefully tighten (turning clockwise) the retaining nut with an adjustable wrench. If the drip continues or gets worse, turn off the water and remove the nut to repair the faucet. (Note: Some faucets may have reverse threads to prevent the retaining nut from becoming loose, so you may have to check which way is tightening the nut.)

2. Remove the Stem Assembly

To remove the stem assembly, remove the packing or retaining nut and reinstall the handle. Open the valve completely and keep turning so that the threads of the stem exit the valve body. Once the threads are clear, gently pull the handle straight out and the stem assembly should come out easily.

3. Replace the Washer and O-ring

Depending on the type of faucet, you may only need a new washer, but some will also require a new o-ring and metal washer. Most hardware stores and home centers sell repair kits that include all of the parts you will need. Keep track of the parts as you disassemble the faucet so you can install the new ones in the same order.

4. Check the Vacuum Breaker Assembly

All frost-proof faucets have a vacuum breaker which allows the water to drain out of the valve and prevent cross-contamination. Remove the vacuum breaker cap to access the parts underneath. The cap snaps into place and you can remove the cap by prying it off with a screwdriver.

Removing the Vacuum Breaker

Vacuum Breaker parts

Unscrew the retainer and pull out the vacuum breaker. Sometimes debris from the inside of the pipe gets trapped in the ports of the vacuum breaker and you may be able to fix the leak by simply cleaning the parts and reinstalling them. If there is excessive scale build up, you are better off replacing the components with a repair kit.

After all of the components have been cleaned or replaced, turn on the water and check the operation of the faucet. The water may be slightly dirty when it first comes on. Open and close the valve a few times to make sure it shuts off completely after the water has drained out of the valve.


john doe
Posted on Oct 2, 2011
Amera Khanam
Posted on Sep 21, 2011