How to Replace a Frost-Free Outdoor Spigot (Sillcock)

Locate the main water shut-off valve for your home, which is typically found in the basement, a utility closet, or near the water meter. Turn the valve handle clockwise until it stops to completely shut off the water. Next, open the outdoor spigot you are replacing and the lowest faucet inside your home (e.g., a basement sink) to drain as much water as possible from the plumbing system.

Go to the area inside your home (basement or crawlspace) directly opposite the outdoor spigot. You will need clear access to the pipe where the sillcock connects. You may need to move stored items or push aside insulation. If the connection is behind drywall, you will need to cut a small access hole using a drywall saw.

Before disconnecting anything, use a tape measure to determine the length of the existing sillcock. Measure from the back of the exterior mounting flange to the center of the interior pipe connection. You must buy a new frost-free sillcock of the exact same length. Also, verify the connection type (in this case, a 1/2-inch or 3/4-inch female sweat connection) and the pipe size to ensure compatibility.

Drape a fire-resistant cloth over any wood joists or other flammable materials directly behind the solder joint. Put on safety glasses and heat-resistant gloves. Using a propane torch, apply heat evenly to the fitting where the sillcock connects to the copper pipe. Do not heat the pipe itself. Once the solder begins to look wet and shiny, use a pair of channel-lock pliers to grip the sillcock's pipe and gently twist and pull it off the copper water line.

Move to the outside of the house. Use a screwdriver or a drill with a driver bit to remove the screws that secure the sillcock's mounting flange to the siding. Once the screws are removed, firmly grasp the spigot and pull the entire assembly straight out of the wall.

A clean pipe is essential for a leak-proof solder joint. Use an emery cloth to sand the outside of the copper pipe end until it is bright and shiny, removing all old solder and oxidation. Then, use a fitting brush to clean the inside of the new sillcock's connection point until the copper is equally shiny. Wipe both surfaces with a clean, dry rag to remove any dust or debris.

From the outside, carefully guide the new sillcock through the hole in the wall. Ensure the spigot nozzle is pointing downwards. Go back inside. Apply a thin, even layer of lead-free flux with a small brush to the cleaned exterior of the copper pipe and the cleaned interior of the sillcock fitting. Firmly push the sillcock fitting onto the end of the copper pipe until it is fully seated.

Place the fire-resistant cloth behind the joint. Heat the fitting with the propane torch, focusing the flame on the thickest part of the fitting, not the pipe. After about 15-30 seconds, touch the tip of the lead-free solder to the joint on the side opposite the flame. The heat from the fitting should instantly melt the solder, which will be drawn into the joint by capillary action. Move the solder around the entire circumference of the joint until you see a continuous silver ring. Remove the heat and allow the joint to cool naturally for several minutes. Do not touch or disturb it while it cools.

Return to the exterior of the house. Align the sillcock's mounting flange with the holes in the siding. Ensure the sillcock is pitched slightly downwards toward the outside to promote proper drainage and prevent freezing. Secure the flange to the wall using new corrosion-resistant screws. Do not overtighten.

Using a caulking gun, apply a continuous bead of 100% silicone or exterior-grade polyurethane sealant around the entire perimeter of the sillcock's mounting flange. This creates a weatherproof seal that prevents water, air, and pests from entering the wall cavity through the penetration.

First, ensure the new outdoor spigot is in the fully closed position. Go to the main water shut-off valve and open it SLOWLY, turning it counter-clockwise. Listen carefully for any sounds of rushing water, which could indicate a major leak. Once the valve is fully open, return to the basement/crawlspace and meticulously inspect the new solder joint for any signs of moisture. Wipe the joint with a dry paper towel to make it easy to spot even the smallest drip. If the joint is dry, the installation is complete. Go outside and test the new spigot's operation.