The toilet shutoff valve that will not turn
Quick answer
Old multi-turn shutoff valves often seize or leak when you try to close them. Replacing them with quarter-turn valves and new braided supply lines means you can stop the water fast when you need to.
The shutoff valve behind a toilet is easy to forget until a toilet starts to overflow. In older San Gabriel homes, those valves have often been sitting untouched for decades.
Why old valves fail
Multi-turn valves use a rubber washer that hardens with age. Mineral deposits build up inside. When you finally turn the handle, it either will not budge or starts leaking at the stem.
Test yours
Turn the handle gently. If it moves smoothly and stops the water, it is fine. If it is stiff, leave it and plan to replace it.
Quarter-turn valves
New quarter-turn valves open and close with a 90-degree turn. They are less likely to seize, and you can tell at a glance whether they are open.
Supply lines
Old rigid supply tubes can crack. Braided stainless lines are flexible and durable, and we replace them with the valve.
Connection types
Valves connect to the pipe by compression, threads or solder. Older homes may have galvanized or copper stubs. We match the fitting to the pipe.
Galvanized stubs
In some older San Gabriel homes, the pipe coming out of the wall behind the toilet is galvanized steel. Over time, threads corrode and the pipe narrows inside. When we replace the valve, we inspect the stub.
If it is badly corroded, a short new nipple at the wall makes the new valve last longer.
Toilets that keep running
A worn shutoff often goes hand in hand with tired parts inside the tank. While the water is off, it is a good time to replace the flapper and fill valve, so the toilet works properly for years.
Sink valves at the same time
If the toilet valve is seized, the valves under the bathroom sink are likely in the same condition. Replacing all of them in one visit means one water shutdown and one trip.
Know your main
Since replacing an old valve usually means shutting off the main, it is worth confirming where your main shutoff is and that it turns. If the main itself is old and stiff, we can look at that too.
Why old valves fail
The small valve behind or below the toilet is called an angle stop or supply stop. In many older San Gabriel homes, these are multi-turn valves decades old. Inside is a rubber washer that hardens and cracks.
Over years, mineral buildup seizes the stem. When you finally need to turn it off, it will not turn, or it leaks from the stem, or it closes but water keeps flowing.
Testing a valve
Turn the valve clockwise until snug, then flush the toilet. If the tank does not refill, the valve works. If it refills, the valve does not seal.
Check the stem for drips when you turn it back on. If the valve will not turn by hand, do not force it with a wrench; old valves can break.
Quarter-turn valves
Modern quarter-turn ball valves close with a quarter turn and do not depend on rubber washers. They are far more reliable. Replacing an old valve requires shutting off water to the house.
Our steps:
- Shut off the main water valve and drain the line
- Remove the supply line and old valve
- Clean the pipe and install a new valve with the right fitting
- Install a new braided stainless supply line
- Turn on the water and check for leaks
Pipe types
Older homes may have galvanized steel pipe, copper or a mix. Galvanized pipe threads can be corroded and fragile. Copper pipe uses compression or soldered fittings. We check what you have before starting.
Supply lines
Supply lines connect the valve to the toilet tank. Old plastic lines crack, and old metal lines corrode. Braided stainless lines are reliable. Replace both the valve and line together.
Main shutoff
Know where the main water shutoff is. In many San Gabriel homes, it is near where the water line enters the house, often near a hose bib in front. Test it once a year.
Other valves
Sinks, washing machines and water heaters also have shutoffs. Replacing all old valves at once saves time and water shutoffs. See dripping faucets in older San Gabriel bathrooms.
Valves coming out of the floor
Some older toilets are fed from a pipe coming up through the floor rather than the wall. Those need a straight stop instead of an angle stop. The pipe may be galvanized or copper.
Floor pipes rust at the floor line, and when the valve comes off, the pipe may need a short section replaced.
Escutcheons
A chrome cover plate, called an escutcheon, hides the hole where the pipe enters the wall or floor. Replacing a rusted one gives a clean finish.
When to call
If the pipe at the wall is badly corroded, if the main will not shut off, or if you are not comfortable cutting and fitting pipe, call us.
What our visit involves
We shut off the main, replace the valve and supply line, turn the water back on and check for leaks. While we are there, we can replace valves under sinks too. See plumbing fixes.
After swapping a few shutoffs near Las Tunas Drive, a late lunch at Newport Seafood is our usual reward.
Want us to handle it?
Call or text (626) 684-3505, Mon–Sat 8:30 AM–7 PM. Send a photo and we will give you an upfront quote.
Call or text (626) 684-3505