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I am experiencing water hammer at my basement shower. This is the only place in the entire house that causes this problem, and it seems to favor the cold water line. I have a gas hot water heater, and it does not have an expansion tank on it. This problem started about a month ago.
I seem to recall that if I were to sweat a “T” into the line and add a piece of copper pipe with a cap soldered to that, that it would solve the problem, however, I’m not sure. Can anyone give me an inexpensive fix for the problem? Thank you.
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my grandfather is a retired plumber. my job as a kid was to make air chambers using a tee with a cap on it. I dont know if they do any good but we put them on every job. The plumber i use now says they are worthless and get saturated with water. I dont know. I do know some of the scald guard showers can be adjusted to eliminate water hammer.
*Gary,One physical property of water is that it will take on air. Over time, the air in air chambers (and expansion tanks that do not have a membrain) will be absorbed and they lose their effectiveness. It is possible you have air chambers (most usually at your washing machine and possibly at other locations as well) and the one for your cold water line has become saturated. The easy fix is to turn off the water supply to your house and drain your system down. When water is restored air will again be captured in the chambers. If this does not work, you can sweat in a tee and add a chamber. I do not like the chambers that you can buy at the plumbing supply or the ones most folks make up out of 1/2" copper tubing. I think they are too small and prone to saturation. I like to make them up out of 1" tubing at least a foot long. Water hammer is the result of valves that shut quickly. Washing machines have automatic valves that shut very fast. For this reason, air chambers are almost universaly included in washer hookups. Faucets with screw type valves and water closet valves close slowly and do not, as a rule, cause water hammering. However, the newer single handle valves can be closed very quickly and will generate hammering. It is best to include air chambers at all locations with these types of valves. I would not open a wall to do this but if I had a hammering problem that could not be cured by draining the system down I would add one on the hot and cold lines at an accessable point in the system.
*Water hammer is most likely in long straight runs that,like Steve described, gts closed quickly. Probably too late to reroute the pipes so I'd agree with the drain-down first approach. If that doesn't helo enough, find an easy place near the end of the line to put an air chamber. Ideally the end of a long run will turn towards the fixture and continue straight towards the air chamber. The air will then more effectively cushion the momentum of the moving water. -David
*If your basement shower is on the same water line as your washing machine, you can install in-line water hammer arrestors at the washing machine taps. They're available at most home centers. They have a piston in them, so they aren't affected by orientation or air saturation.
*Ditto. Also, if you can enlarge the line to the bathroom it will slow the water flow -- or add a flow restrictor at the shower head. High-velocity flow through undersized pipes shut off abruptly is supposed to be the problem... all this leads to accelerated pipe decay..
*And the are hose threaded, so they just go in line between the washing machine valve and hose, no real plumbing.
*In the Tauton book "Plumbing a House", the author suggests making a series of air chambers out of 1" pipe right after the water meter. He uses a coupling so he can remove the air chambers to drain them periodically. Anybody try this yet?Also, I want to make an air chamber out of a clear material and hook it up so I can actually see if and how long it takes for these air chambers to fill up with water. I want to duplicate the conditions found in conventional piping as close as possible, maybe use 3/4" material.Any suggestions(sp) as to the materials and where to locate them?ThanksJeff [email protected]
*Jeff,Thanks for the idea. After getting bored with my current home activities, including timing how long 2,4-D takes to kill dandelions, testing window caulk resiliency at various temperatures, weighing furnace filter dirt, and working on achieving an exact plus or minus two degrees HVAC balance between rooms, it's great to hear of a new one. The clear water hammer arrestor will need to have some predetermined, standard measuring context and tell-tale. Please include me in any discussions on such standards so that we may compare our results later on.
*I had a water hammer which announced itself very clearly from both my single lever kitchen valve and the dishwasher. I installed hammer chambers under the kitchen sink, thinking this was the end to my problems. Unfortunately, I have to drain down the system about every 3 months or the pipes start hammering again. Seems like and awfully short time for the air in 16 inches of 1/2 inch pipe to be absorbed, doesn't it? I guess if I had made them out of larger pipe I would be able to last longer between draining.
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You can build a water hammer chamber that can be drained by installing a shut-off valve with a small drain cap in the upstream side of the valve body (like in hose bib shut off valves), below the air chamber. Then, periodically, shut off the water supply to the chamber (using the shut-off valve, not the whole house water supply valve) and open the drain cap to drain off any accumulated water and let in a new supply of air.
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I am experiencing water hammer at my basement shower. This is the only place in the entire house that causes this problem, and it seems to favor the cold water line. I have a gas hot water heater, and it does not have an expansion tank on it. This problem started about a month ago.
I seem to recall that if I were to sweat a "T" into the line and add a piece of copper pipe with a cap soldered to that, that it would solve the problem, however, I'm not sure. Can anyone give me an inexpensive fix for the problem? Thank you.