Crazy Plumbing Mystery - valves are on, water stops running?

Question

When filling a bath tub the water runs for a few minutes but then with a loud thump or hammering sound stops running.

If I turn off the handles, wait a moment and turn them on it will run a few seconds before doing the same thing.

The same thing happens if I use, either or both of the handles.

The two valves are connected to a Tee which is connected to a 3/4inch washing machine hose which is connected to the tub. The bath tub has a integrated fiberglass waterfall spout with a 3/4 threaded connection.

The noise is loud. I cannot tell if it is in the tub or behind it, but I suspect it is behind it.

The access panel does not give me access to this side of the tub.

Sometimes it leaks a trickle, but most of the time it shuts off completely.

It is upstairs, all of the other faucets, sinks, toilets work fine. Water pressure seems fine. Connected to city, not well.

Thanks thanks thanks!

The bath tub is new. It has been used about 6 times. Before this happend It always too long to fill, 30 or more minutes.

Answer 1

When you say this happens with either of the handles - then you have tried to fill the tub with cold water only? And it still happens? Then it can't be scald protection.

I believe there must be something between where the two lines meet at the T connection and the tub spout.

Answer 2

I've had funny things happen with scald-guard faucets and this sounds like it might be related. Has this problem just started with an old faucet or did you install a new one that won't work right? If it's old, take the stems out and look at "O" rings and washers. Have any pieces broken off? If so there could be a piece lodged in the mixing valve. Does the faucet have internal stops (more common on high end faucets so you can cut the water off at the faucet to remove the stems instead of cutting the water off to the entire house)? If so, make sure they (the stops) are turned all the way on. If they are already all the way on, turn them off and remove the stems and look for broken/missing "O" rings and washers. It's anyones guess how these things regulate temprature; they're pretty complicated. If the problem isn't fairly obvious it's probably best to replace the valve. At least that's been the suggestion from my high priced plumber.

Answer 3

The faucet may need internal parts replaced. However, the loud thump you hear may be water hammer. This can break pipes! You may have an air bubble in the line where you don't want one. Usually there is a pipe that rises up into an attic space where it is capped off. this is to create an air chamber which acts as a dampener when water flows. The rest of the system is always to be full of water. Over time, this pipe can fill with water and the dampening effect is lost. If this is part of the problem, turn off the water supply to the house, open your drain valve at the lowest point and then upstairs faucets too to let the system empty itself. You will not drain your hot water tank because it relies on water pressure to push water through the pipes and you will have eliminated that. After all the water has drained, open the water supply first, then go to the open faucets and close them when water comes out in a steady stream. They may spit and gush a bit until they have refilled.

If this doesn't fix it, call a plumber.

Answer 4

I would think that there is something in the pipe and won't go threw the valve.. When you shut the water of it falls back down. Turn water on it comes back up and hits the valve. Probably a chunk of washer from an other part of the house Shut the main off.Take both handles off and guts run water and it will flush out.

Answer 5

You have air in the copper lines...

Turn on every faucet in the house and allow all to run until no noise is noticed.
Then you can turn off all the valves; second floor first.

The above problem is usually caused from repairing/replacing a valve since you would of had to drain the copper line to allow the solder to melt.
Sadly, you forgot to purge the complete system afterwards and an air bubble was introduced.

Read the below link for more details:

http://www.factsfacts.com/MyHomeRepair/PipeNoises.htm

Answer 6

You have to undo the little bolt in order to replace the washer. You can also buy the valve assembly to replace the leaky one'

Answer 7

the hose has a liner that may be broken loose and it will bunch up and plug up.when it plugs loosen the output end of the hose and see if you have any flow.

Answer 8

I would think it was the washers in the valve controls