How to Stop a Freeze Proof Faucet from Leaking is a repair that the family handyman can do.
In climates with freezing winter temperatures, a frost-proof sillcock faucet is an excellent choice since it prevents water from remaining inside the faucet near the exterior wall, which can cause it to split.The parts of a frost-proof faucet can wear out and need to be replaced.
The valve mechanism that seals off the water flow is located back inside the house, away from the exposed exterior portion of the faucet.In older types of faucets, a long valve stem operates a rubber washer that compresses down against a valve seat located well inside the house where it remains too warm to freeze.Whenever the faucet is shut off, the water inside the pipe will drain out.It cannot freeze, expand, or break because there is no water in the pipe.The newer designs have a long valve stem and self-draining feature, but they don't use a rubber compression washer, like most indoor sink faucets.
There is a vacuum breaker mechanism in newer frost-proof sillcocks.Older frost-proof faucets may not have this feature.
There is a packing cord wrapped around the handle stem on older faucets that use compression washers.There is a chance that the handle mounting nut is leaking.
A frost-proof faucet can leak from the anti-siphon portion of the valve.If you want to repair it, you will most likely need a brand-specific rebuild kit for your faucet.You can purchase rebuild kits from a plumbing supply house or a hardware store.It is a good idea to call ahead to see if they have rebuild kits for your brand.To make the repair, shut off the water.
If you have trouble finding replacement parts for a frost-proof hose spigot, it may be more cost-effective to replace the entire faucet.