Banging when opening/closing faucet...

[cool5abi]

Hello All,

I'm super stumped with a problem I've been having with my plumbing for some time. The house is 11 years old (purchased new), and is city fed. I've been hearing the noise for several months now, but only now has it become worrisome (it was very faint and hardly ever happened in the beginning).

Essentially, when opening or closing any faucet (hot or cold) in the house I hear considerable banging from my pipes. In some faucets (second floor baths) I can even feel a knock from the handle of the faucet when the banging occurs. The noise seems to be loudest just a bit away from a shower/bathtub in the second floor bath, I believe the banging can be felt in the floor as well. I've done the following so far;

1. Made sure all pipes were tight and secure.
2. Replaced the cartridge assembly for both showers.
3. Replaced the seats for the lavatory faucets.
4. Drained and refilled the pipes... a few times. (Hoping to fill the air chambers with air again).

I'm familiar with the principle of water hammer, and I see how it occurs when suddenly stopping the flow of water. But I can't seem to figure out why the pipes would bang when opening the faucet as well. I've opened up the drywall below the tub and can't feel the pipes banging against the joists, so I believe the noise is caused by the water in the pipes themselves. Usually, you will hear 3-4 bangs, almost seems like water is flowing back and forth hitting something.

Since the problem occurs when opening/closing both the hot and cold water, I decided to try one last thing... turn off the supply to the hot water tank. Strangely enough, the banging no longer occurs... What could cause this?

 

[havasu]

Sounds like a loose hot water pipe. That is plausible since the "hot" pipe expands and contracts much more than the cold water pipes. Many have solved it by pinpointing the area where the sound is the most noticeable, and injecting some expanding foam into a little hole punched in the drywall. This can work provided the foam has the ability to expand so that would be my warning to you.

 

[cool5abi]

Sounds like a loose hot water pipe. That is plausible since the "hot" pipe expands and contracts much more than the cold water pipes. Many have solved it by pinpointing the area where the sound is the most noticeable, and injecting some expanding foam into a little hole punched in the drywall. This can work provided the foam has the ability to expand so that would be my warning to you.

I did check for loose pipes, but it's certainly possible that I missed something. However, if it was a loose hot water pipe why would the banging still occur when opening the faucet to allow cold water only (single handle)? Also, when I turned off the HWT supply, the banging still occurred on the cold until I opened the hot side and relieved the pressure; after that everything was silent.

 

[LiQuId]

install water hammer arrestors on the hot and cold lines, sounds like thats your problem, could also be a loose washer in on of the angle stop valves ( if you have them ) tryy isolating different fixtures. if it has completelly stopped by shutting the supply to the hot water tank then look for any kind of check valve on the piping going there, perhaps even the small lift check at the hwt connection. be aware that the sould can and will travel far and may seem to come from a place that is not at all associated with the actual cause.

medical supply stores will sell a stethoscope for 20 bucks that can be usefull to listen to walls and floors to determine if there is a loose pipe that is banging around, though this usually is not the problem.

1 isolate fixtures and make a list of what could be the problem and what definatelly is not.

2. attempt installation of water hammer arrestors if the problem can be somewhat isolated.

3. know that usually this is caused by either a quick acting valve ( such as a faucet or such ) or a slow acting valve installed in the wrong direction ( such as a zone valve in a heating system ) or a check valve, sometimes installed by the city on the main.. has the city done any groundworks in the area since this sound appeared.

I will check daily to help if I can as Im currentlly laid out with broken bones for 2 months. these problems keep me sane.

 

[LiQuId]

havasus foam idea is a easy and decent suggestion, could fix the problem with under 10 bucks. though I;ve rarely experienced lose pipes that bang and do not also creak and moan when the affected fixture is found... still worth a shot.

 

[havasu]

Liquid, what the heck happened to receive two broken bones?

 

[LiQuId]

Im filled with titanium for starters. but last year in october I lofted myself with a traction kite resulting in me free falling 40 plus feet shattering my ankle tib and fib. had an operation and had 2 plates and 12 screws installed. went snowboarding a few times this year and was suprised to be able to ride as aggresively as always, but the other day was the failing point for the hardware, did a light toeside turn which resulted in catastrophic failure of the plates, the one holding my ankle together had etched a line into the bone and then sheared its way through the tibulam the fibula injury higher up by the knee resulted in fracture due to this bone not usually using all its muster to support the limb and I HAD to stop. 2 months recovery for the bone and another 1 for physio... that and future plans to have the hardware removed as i understand this is a common injury after rebuilding a joint and my ability to minimize my pace is not very good. bummer is that i gotta take at least a year off from snowboarding, kiteboarding and downhill biking... all the things I love to do the most, the good is that I didnt require additional surgery, and that this didnt happen on the ridgeline we were scoping out.... wouldve been an expensive heli sling out if it had. \

 

[havasu]

All I can say is "OUCH!" You realize that there is an old saying that if the big guy upstairs wanted us to fly, we would have been born with wings!

Sorry for the derailing of this thread cool5abi, resume the shop talk. //

 

[phishfood]

Ouch it is!! Sorry to hear that, Liquid.

 

[cool5abi]

install water hammer arrestors on the hot and cold lines, sounds like thats your problem, could also be a loose washer in on of the angle stop valves ( if you have them ) tryy isolating different fixtures. if it has completelly stopped by shutting the supply to the hot water tank then look for any kind of check valve on the piping going there, perhaps even the small lift check at the hwt connection. be aware that the sould can and will travel far and may seem to come from a place that is not at all associated with the actual cause.

Yeah I thought it would be typical water hammer too, but the fact that it never happened for the previous 10 years, and that it happens when opening the faucets as well as closing has me wondering otherwise now. Plus, it's not like I have crazy high water pressure, nor am I opening/closing the faucets at a very rapid pace. The banging seems to be loudest and most felt in the second floor bath by the shower, but I'll take your word and see if it's traveling from somewhere else. I've already checked all the basement pipes and little sound and no movement down there.

medical supply stores will sell a stethoscope for 20 bucks that can be usefull to listen to walls and floors to determine if there is a loose pipe that is banging around, though this usually is not the problem.

Anything is worth a shot at this point, I'm stumped!

1 isolate fixtures and make a list of what could be the problem and what definatelly is not.

2. attempt installation of water hammer arrestors if the problem can be somewhat isolated.

3. know that usually this is caused by either a quick acting valve ( such as a faucet or such ) or a slow acting valve installed in the wrong direction ( such as a zone valve in a heating system ) or a check valve, sometimes installed by the city on the main.. has the city done any groundworks in the area since this sound appeared.

1. Hard to isolate the fixtures, it's essentially all of them. One thing for sure, the problem gets worse the higher up in the house I go.

2. This is my last resort, I don't really want to install hammer arrestors at several faucets... ad the drywall paint patching that goes with it.

3. Ironically, the quick acting valves (washer, dishwasher, toilets) don't really cause much of a problem. I don't have zoned heating or any check valves in my house. I don't think the city did any work near my neighborhood...

I will check daily to help if I can as Im currentlly laid out with broken bones for 2 months. these problems keep me sane. [/QUOTE]

The help is very much appreciated! I'm a pretty good DIY'er but this one is testing me. And best of luck for your recovery, that sounds pretty painful.

 

[Tech]

Sounds like you have to much water pressure coming in. You need to put a regulator on the water line to decrease the pressure. Have the water pressure tested before tearing anything apart. Water pressure should be between 60-75 psi. It could be you have a pressure regulator, and it has now failed. A plumber should be called in to make repairs/test water pressure

 

[phishfood]

Also, there shouldn't really be a need to cut into walls to install hammer arrestors. You could install them under every sink and lavatory on the piping coming out of the wall.

 

[Mr_David]

Hammer arresters are probably not going to solve the problem.

You say it occurs when yo open and close any fixture, Not just one in particular.
What type of main water shut off valve do you have? Ball valve, Gate Valve, or a globe valve.
Globe valves have a washer that seals on a seat. If the washer is loose or badly worn it will flutter as you open and close fixtures.
Check the ballcocks in the toilets. You can shut off the toilets and see it you still have the banging. What is the water pressure.
It could possibly be a pressure reducing valve causing the problem.

 

[cool5abi]

Sounds like you have to much water pressure coming in. You need to put a regulator on the water line to decrease the pressure. Have the water pressure tested before tearing anything apart. Water pressure should be between 60-75 psi. It could be you have a pressure regulator, and it has now failed. A plumber should be called in to make repairs/test water pressure

Unfortunately, I don't have a water pressure gauge, so I can't say definitively what the pressure is. I do know based on everyday use, the pressure seems the same as it's been since the house was first built. I can still only use the same number of faucets simultaneously, and the water doesn't come out with any more force than it used to. Yes I know, not very scientific...

I'm sure I don't have a PRV, there's nothing in my house and aside from the underground utility shut-off valve outside, there's nothing else on the supply side. My supply goes as follows;

1. Utility side comes underground
2. Utility shut-off valve (need the big key)
3. Supply continues underground, into the house
4. Main shut-off
5. Water meter
6. Another shut-off valve that I installed.

The reason I installed another shutoff valve (ball valve) is because I finished the basement and it's hard to get to the main one now, plus catching the water when draining the system would be impossible otherwise.

 

[cool5abi]

Also, there shouldn't really be a need to cut into walls to install hammer arrestors. You could install them under every sink and lavatory on the piping coming out of the wall.

Good point, aside from the showers I can do the rest with minimal damage.

However, I still don't want to go that route because firstly it's expensive to install arrestors at every hot/cold at every fixture. But more importantly, I'm still not sold that it'll solve the root problem (effectively). And yeah it is quite time consuming, already have plenty of projects on the go!

 

[cool5abi]

Hammer arresters are probably not going to solve the problem.

You say it occurs when yo open and close any fixture, Not just one in particular.
What type of main water shut off valve do you have? Ball valve, Gate Valve, or a globe valve.
Globe valves have a washer that seals on a seat. If the washer is loose or badly worn it will flutter as you open and close fixtures.
Check the ballcocks in the toilets. You can shut off the toilets and see it you still have the banging. What is the water pressure.
It could possibly be a pressure reducing valve causing the problem.

I don't think hammer arrestors will solve the problem either. The cold water pressure is the same regardless of whether the supply to the HWT is on/off; and considering the noise goes away when the HWT supply is turned off I'm convinced hammer arrestors are not the answer.

Hard to say, but I think the main shutoff is a globe valve, seems a bit too long to be a gate valve. I did turn off every shutoff valve in the house (toilets, hose bibs, washer, some faucets) and the noise was till present. So if in fact it's a loose washer, it's going to be the main.

I'm leaning more towards the HWT being the problem, elsewhere I've read about heat traps being a problem; but I'm not sure if I have them. I do have nipples attached to the HWT but they're only ~1.5" or so, seem a bit short to be heat traps. I've had my wife open/close a faucet while I was near the HWT and while I don't hear any banging in the area, I do hear some slight clanging sound; almost like bits of metal or marbles hitting each other.

The problem continues, but you guys are definitely helping!

 

[havasu]

I had a similar annoying sound after replacing the plumbing in my house. I literally crawled on my hands and knees in the attic and followed every line to the supply line, and discovered my banging came from one of my TWH hot return lines, which was not secure to the studs.

 

[Plumber903]

Check for dripping faucets, and or commode fill valves not shutting off all the way.

 

[Tech]

Here is a link, hope this helps.

Water hammer - Wikipedia, the free encyclopedia

 

[LiQuId]

wow, thanks tech,,,