Repairs
The handle turns but the water keeps running
A shut-off valve has one job and it usually fails on the day you need it. Here is how to tell a valve that can be adjusted from one that has already failed inside, and what replacing a main shut-off actually takes.
If the handle turns freely and the water keeps running, the valve has already failed inside and turning harder will not save it. On an old multi-turn gate valve the brass wedge usually corrodes off the end of the stem, so the stem rises and falls while the gate sits dead in the bottom of the body. On a quarter-turn ball valve, the stem can shear or the ball can score. In both cases the part you are holding is no longer connected to the part that stops water. That valve gets replaced, not adjusted.
One thing is worth trying first. A valve that closes almost all the way and leaves a thin trickle is sometimes held off its seat by scale or grit, and working it fully open and fully shut two or three times can clear it. If three cycles change nothing, stop there. Forcing a fifty-year-old stem is how a slow drip becomes a flooded cabinet at nine on a Sunday night.
Which valve are you holding?
Angle stops under fixtures
These are the small chrome valves under sinks and behind toilets, one for cold and one for hot, each feeding a single fixture. They fail more often than anything else in the house because they sit untouched for decades and are then asked to work once, in a hurry. Older ones are multi-turn with a rubber washer that has gone hard as a coin. Newer ones are quarter-turn with a ball inside. A failed angle stop is a small, contained job.
The main valve for the house
On most Costa Mesa homes this sits on the exterior wall near the front hose bib, or in a small box in the planter close to it. It shuts everything, and it is the valve that matters at two in the morning. It is also the one most likely to be original to the house, which on a 1970s build means a gate valve that has not moved since the plumber who fitted it drove away.
The meter and the utility side
Out near the kerb there is a meter box, and inside it a valve on the street side of the meter. That side belongs to the water provider, which for most of Costa Mesa is Mesa Water District, and it is not homeowner equipment. There is usually a second valve on the house side that can be operated with a meter key. Working out which is which on a dry afternoon takes five minutes and saves twenty in an emergency.
Why so many valves here fail the same way
Costa Mesa’s housing stock has a median build year of 1972, and roughly two thirds of it went up before 1980. That puts a great many original gate valves at fifty years and counting. Then there is the water itself. Mesa Water District supplies the city entirely from local groundwater, drawn through nine wells into the Orange County basin, and groundwater carries minerals. Those minerals settle on stem threads and on the seat, so a valve that is never exercised slowly cements itself in place. The handle still turns. The gate does not.
Weeping at the stem is a different fault
If the valve does shut, but water seeps out around the base of the handle while it is open, that is the packing rather than the seat. On many valves the packing nut sits directly under the handle, and an eighth of a turn with a wrench stops the weep. Overtighten it and the stem binds, which produces exactly the failure described at the top of this page. If the nut is already tight and it still weeps, the packing itself is spent, and the valve gets rebuilt or swapped.
When a repair is honestly the right call
A sound valve with tired packing does not need to be cut out of a wall, and we say so.
When it gets replaced
Replacement is the answer when the valve will not shut, when the body is green and pitted, when the stem spins without resistance, or when it is a gate valve serving the whole house. That last one is a judgement call and it usually goes toward replacement, because a main gate valve that has to be forced closed will often refuse to open again afterwards. A bathroom repair then becomes a house with no water. A quarter-turn full-port ball valve in that position still moves when it is asked, twenty years later.
What replacing a main shut-off actually involves
There is no valve upstream of the main on the homeowner’s side, so the water has to be stopped at the meter first. Sometimes the meter-side valve is stiff too, and that becomes a conversation with the district rather than something to force with a pipe wrench. Once the water is off, the work itself is a short window: cut out the old body, clean the copper back to bright metal, and set the new valve with press or soldered fittings depending on what surrounds it. On a slab home the pipe often rises out of the ground straight into the wall, so there is a foot of working room and no more. It is not a long job, but it is a job with no undo, which is why it gets set up properly before anything is cut.
If the valve failed in the middle of a leak
Stop the water at the meter with a meter key, or close the angle stop nearest the leak if that one still works. Once the water is off and nothing is running, a valve replacement can usually wait until morning, and we will tell you that rather than sell a night call. If the water cannot be stopped at all, that is a call to make now. A person answers the phone at any hour and the vans run out of Costa Mesa across Orange County.
Five minutes that prevent the emergency
Once a year, find the main valve and every angle stop and turn each one fully closed and fully open again. Valves that move keep moving. While you are down there, write on a strip of tape which valve feeds what, and put a meter key somewhere you can find in the dark. Most panicked shut-off calls are not really about a broken valve. They are about nobody knowing where the valve is.