Is it safe to shut off old toilet valve?

Old 05-17-24, 02:40 PM
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Is it safe to shut off old toilet valve?

I need to shutoff all the toilet valves in my house (3 total) to narrow down a slow water leak.

But I have a fear that the valve may be sticky due to lack of use, and turning it may put a torque on the compression fitting and cause it to break the compression seal and therefore create a leak.

Is this fear unfounded?
Old 05-17-24, 03:01 PM
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Of ALL things, I am certainly not a plumber so wait on the experienced guys to give advice but in my opinion & experience, old toilet valves that haven't been worked in a long time, are notorious for leaking once turned... IF you can get it to turn. Also, the handles are likely to strip & turn on the splined valve shaft & come off in your hand. At that point, you'll need a good pair of vice grips. Then a new valve.
Old 05-17-24, 03:34 PM
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I would have a replacement at hand.
Old 05-17-24, 05:34 PM
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Use a wrench to hold the valve housing and avoid torquing the compression fitting. Also use some WD40 or PBBlaster to free up the shaft and work the valve handle back and forth to loosen it before shutting off completely.
Old 05-18-24, 06:11 AM
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The point should be that those valves should function. If they leak they need to be fixed. If the hose to the toilet ever develops a leak or if the toilet needs maintenance the valve needs to work. So, now is as good a time as any to check them. Plus, valves don't develop leaks if they are used occasionally so opening and closing the valve regularly is a good thing.
Old 05-18-24, 07:47 AM
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I have two toilet shut off valves in my plumbing box. They have been gathering dust for years, but if I ever have a shut off valve that leaks I would just replace it. They are cheap.

I agree that cycling a valve occasionally is a good idea. It also ensures that when you need to operate the valve it isn't seized. That's especially true of gate valves.


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