My girlfriend's shower is a two-handle w/ diverter. It is a Delta from early '80's, I think. I replaced the handles, stems, extensions (to get it past tile wall), seats and springs 3-4 years ago.

When she wants to soak in the tub, she fills it 1/4 way with only hot water, then turns cold on to finish. For some months, after the hot has run a while like this, the cold will not come on--the handle turns, she says 'it clicks', but no water comes out. After about 30 min of sitting and no water use, both work again. I think if she runs a little bit of cold, then the hot on 100%, it is ok.

What could this be, how do I start to fix it? She does not remember to run the cold first, and I'm hoping it is not going to lead to something worse.

Thank you for all suggestions.

sorry, but what you describe makes no sense in the plumbing world.
nothing should 'click' when you turn the cold handle..

I know. That is why I'm baffled....just going on what I was told over the phone.

What could be heating in the manifold that would block the cold water? There are 3 plastic extensions to bring the handle out of a plaster wall that is covered with tile...perhaps the handle isn't tight, and the 'click' is it slipping? I've used it (for a shower, not a bath) and the hot handle is looser than the cold.

i thought of that too. but, if the handle is not engaging the stem, waiting 30 minutes will not make it better.
it will either work or not work..

Only thing I can think of is some sort of heat-expansion.
I think it's all copper pipes, so shouldn't be a chunk of galvanized rust caught in the manifold (if I have that name correct...where hot and cold mix to come out to spout).

I'll see what I can find out over the weekend, and will share....what I fix or am still baffled by!



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Your description is "illogical" which means we cannot help you without being there to actually see what happens and when. There is NO connection between the hot water and the cold water handle, and the cold water handle is fastened DIRECTLY to the cold water valve so turning the handle would normally have to turn the valve and open the cold water's flow.

Delta handles CANNOT "slip" unless they completely disintegrate and then they do not work at all.

they can not slip but as the person said, there were some sort of extensions installed and maybe they can slip ???

The OP is getting bad information over the phone, HJ is correct. Something is happening, but a professional needs to be on site to recreate and evaluate the problem.

Both are secured with "D" openings so they either work or do not work.

that makes sense..

I was able to recreate the trouble. When only hot is run for 10 gallons (about 1/4 tub), the cold water tap will not work. The "click" described over the phone is the handle (1/4 turn on, 1/4 turn back off) being repeatedly tried...as there is no incoming pressure, there is a "click" sound when cut off. I thought it was a ratchet-type as continuously turned.

I know hot and cold pipes are not "connected", heat expansion is only thing that makes any sense to me. The manifold inside the wall is the only place they 'connect' to each other, my guess is something is inside it that swells shut when hot, blocking the cold side. Why there is no pressure at the handle is odd, though. After 20+ minutes of cooling/waiting, cold water works again.

I had left cold tap open to see if it would start flowing on it's own as it cooled, but got the demo of on/off/on/off so show the 'click' and in that process the cold started again.

I did not pull stems/extensions out or do anything else with this, but did confirm I can re-create the situation. Next experiment is to crack cold water as hot is on full to see if it shuts cold off. When off again, I want to leave cold tap open to see if flow returns on it's own.

Any other suggestions? It'll be a couple weeks before I investigate further, unless done over the phone with her.

Unless you get more information, what you describe makes no sense, unless you have cracked the extension, but that would have nothing to do with the hot water being on or off.

May be the tab of your cold water is not working properly or something got stacked into the holes of it. So clean it properly and then also if it doesn't works then may be you need to call a plumber.