A toilet valve, typically located on the wall behind your toilet, controls the water supply to your toilet tank. If you notice any leaks from your toilet valve, you will need to replace it. A damaged or leaking valve can cause further damage to your main water supply pipe and toilet.

The first step in replacing your toilet valve is to assess its condition. Not all leaks from your toilet valve are serious. A loose lock nut or water pipe connection can cause a minor leak. In such a case, reviewing your screws and water line connections can fix the problem. Conversely, if your valve constantly leaks, we advise replacing it. 

Always be patient while working on your toilet valve. Even though they are made to be durable, the connection between your valve and water pipe is delicate. Your valve attaches to a thin water pipe extending from the wall. Any cracks or breaks on the water pipe can lead to an expensive repair procedure. 

IMPORTANT TIP – Do not use excessive force to remove your existing toilet valve. It can cause damage to your main water supply line.

Before starting to work on your toilet valve, shut off your main water valves. Locate these valves in your basement. Typically you will spot them 3-5 ft from the main water supply line entering you house. Once you close these valves, open a faucet at the highest and lowest point in your house.

The objective is to drain any excess water stuck in the pipes. Additionally, we want any air trapped in the pipes to escape before we begin replacing our toilet valve. Toilet valves come in various types, the most common are –

• Sweat Valves
• Compression Valves
• Push-Fit Valves

Each of these valves has different installation procedures, which we discuss below. You can replace any of these valves with its counterpart. Make sure that you thoroughly read the requirements mentioned below before starting on the repair work. Additionally, if you are installing a new toilet, we advise replacing your toilet valves at the same time. If your valves are old, you should replace them to avoid future leaks or problems with your new toilet.

Average Cost To Replace A Toilet Valve

It can cost you between $30 – $75 to replace a toilet valve.

Time Required

To avoid damaging your main water supply lines and any leaks after installation, work patiently to replace a toilet valve. This project will take you between 30 minutes to an hour to complete.

Tools & Materials

• Adjustable wrench
• Safety Gloves & Goggles
• Pliers
• Hacksaw
• Solder Wire
• Blow Torch
• Emery Cloth
• Flame Protection Cloth
• Sandpaper

Replacing Your Toilet Valve

Sweat Valves –

These are one of the commonly installed shut off valves. A sweat valve does not have a hexagonal nut connecting it to the copper pipe protruding from the valve. Additionally, you can replace a toilet sweat valve with a compression valve if needed.

Removing Your Sweat Valve

• Holding the valve with a pair of pliers, loosen the packing nut located directly behind it.
• Once the nut is loose, pull the valve stem to remove it.
• Additionally, observe the inside of the pipe to remove any washers or debris.
• Sweat valves require soldering to attach them to the copper pipes. To detach the valve from the pipe, you will need to melt the solder using a blow torch.

IMPORTANT TIP – We advise covering the wall behind your valve with flame protection cloth. Additionally, always wear protective equipment while using a blow torch.

• Locate the existing soldering on your valve and aim your flame towards it.
• As you notice the solder melting, using a pair of pliers firmly pull on the valve to remove it.
• Furthermore, wipe the copper pipe using an emery cloth to remove any excess solder.

Attaching A New Sweat Valve

With your copper pipe clean of any other solder, you can begin to attach your new sweat valve.

• Apply solder flux to the inside of your new sweat valve and onto the copper pipe. The solder flux helps to prevent damage to the valve and the pipe due to the heat from the blow torch. 
• Thread your valve onto the copper tube and turn it to the desired position.
• Ignite your blow torch and focus the flame on the point where your valve and tube interconnect.
• You’ll need to apply heat to the area for 20-30 seconds before beginning to solder.
• Furthermore, to check if your connection is hot enough for soldering, touch the pipe with the solder wire. If the solder melts on impact, remove your flame.
• While the pipe is still hot, evenly distribute the solder around the circumference of your pipe and valve connection.
• Lastly, allow your valve to cool and turn it to the off position.

To check if your valve is correcting installed, open the main water valve. If any water leaks from the valve or pipe connection, you will need to re-install the valve.

Compression Valve

This type of valve will have a hexagonal nut connecting it to the copper water supply pipe. Additionally, there will be another hexagonal nut directly behind the valve handle.

Removing Your Compression Valve

Similar to the sweat valve, using a set of pliers, hold the valve handle in place. Use a wrench to grip the compression nut and turn it clockwise to loosen it. Once loose, pull the valve to detach it.

Additionally, you’ll need to remove the compression sleeve. The sleeve is a thin brass ring attached to your copper pipe. Grip the sleeve with a wrench and turn to loosen it. If the ring is stuck, you will need to saw it off.

Using a hacksaw, saw vertically through the sleeve. Apply enough force to cut through the sleeve, but ensure you do not damage the copper pipe below. The easiest way to remove the sleeve is to insert a small flat-blade screwdriver into your cut and twist it to break the sleeve.

Furthermore, after removing the sleeve, detach the compression nut and clean your pipe using sandpaper.

Installing A New Compression Valve

• Thread your new compression nut onto the copper pipe.
• Additionally, place your new sleeve onto the pipe as well. 

IMPORTANT TIP – We advise attaching the new sleeve a few centimeters ahead or behind the old sleeve’s location for optimum fitting.

• Apply a thin coat of pipe dope onto your sleeve before installing your new valve.
• With the compression nut and sleeve in place, place your new valve onto the copper pipe.
• The end of the valve is threaded, to which your compression nut will attach.
• Holding your valve in place using a set of pliers, following your manufacturer’s instructions, tighten the compression nut.

Overtightening the nut can damage your pipe and the valve. Hence, it is important to adhere to the manufacturer’s instructions about attaching your compression nut. 

Push Fit-Valve

This type of valves require no nuts or soldering to install. But there are certain requirements you need to meet to install a push fit-valve –

• You’ll need a minimum of 1 inch of copper pipe to install this valve. With a flange, your pipe’s total length extending from the wall should be at least 1 1/2 inches. 
• Your copper pipe needs to be free of any solder, dents, or damage. 

The valve has a pre-attached washer and a connecting fixture on the inside. Simply thread the valve onto the copper pipe and push until you feel resistance.

Once your choice of toilet valve is firmly attached, proceed to connect your water supply lines. One end of the supply lines will connect to the top of your valve. Conversely, the other will connect to the bottom of your toilet tank. Wrap the threaded ends of the water supply lines with teflon tape before attachment. The tape boosts durabilty and prevents against future leaks.

Lastly, open your main water supply valve followed by the shut-off valve. Check the supply line connections for possible leaks and wait for your toilet tank to fill. Flush multiple times to review if all your connects are firm are leak-free.

Frequently Asked Questions: How To Replace A Toilet Valve

Can I replace my sweat valve with a different type of valve?

Depending on the size of your water pipe extending from the wall, you can attach a new compression or push-fit valve.

Can I re-solder a sweat valve to stop a leak?

Never try to re-solder a valve, it will lead to damage to your water pipe. Always install a new valve.