Noise From Water Pipes

Judging by what you have said, I'd just turn the volume up on your radio.

Moving water will make noise. Restrictions will cause turbulence that will make even more noise.

Live with it.

It sounds like you have debri or air in your water lines, but without hearing the noise it's hard to say....It's possible you have cavitation occurring somewhere in the system from too much pressure(positive or negative), too much velocity(undersized lines or oversized pump)...You need a hydraulic engineer to look at the design and installation...

Mostly, no. water is an excellent carrier of sound... Now filling it full of styrofoam is another matter.

seriously, it's hard to say, we don't know what's causing it.

• Well pump/pump on a connected line turning on/off
• water hammer from a connected line
• little Jimmy across the road messing with you
• etc...

from what little information you have you have two options

1. Lyn's recommendation with the radio
2. buy some cheap pipe insulation

remember no guarantees

Special sound absorbing piping is available to reduce noise, but since this is already installed perhaps sound absorbing insulation would be an option?

What's the noise sound like? Are you sure it isn't the natural noise from inside the air conditioner (they are noisy).

Google hydraulic accumulator noise control.

Since you mention that the water is used for air conditioning in a high rise building, I'm going to assume (I know one should never assume) that the water is being pumped from a lower floor up or an upper floor down.

Have there been any changes to the piping system, pump replacement(s),or both?

If so I would agree with those posters who suggested the possibility of pump cavitation, and those who recommended that you engage a hydraulic engineer.

Also has the problem been definitely due to the water or is the fan or any other component of the system contributing to the noise?

Lots of different noises available in closed loop chilled water systems.

First the pump (& or pumping) noises.The motor operation can & will resonate throughout the piping (especially harmonics).

Usually the abatement starts with a flexible connector of sorts that will also assist with the pump installation.Followed by flexible (which by their nature provide a level of vibration dampening) connections at each branch or floor level of your highrise.

Then the A/C fancoil unit itself can be isolated with flexible piping connections.

More importantly is the flow control at each level and/or fancoil unit.The bldg. prints will specify the PSI drop across any chilled water flow control devices at the fancoil.If not then whatever flow is available will try to go through each fancoil...more than neccessary.And now you have a hydraulic trumpet making all sorts of various hisses & squeals & their harmonics.

Has someone figured they can 'save energy' by reducing the chilled water temperature & increasing the flow through the fancoil units?

Maybe those troublesome flow devices (if installed) we're opened up all the way cause the cat lady' fancoil unit was plugged with cat hair and wasn't 'working right'?

Maybe a leak repair required the flow device to be utilised as a shut off (service) valve?

Lots to play with,have fun.

J

Agree with previous posts. Another possibility may be that the system is not balanced properly. If too much flow in some branches, higher velocities could contribute. Also, if overall flow is more than needed, higher velocities across balance valves or other components generally contribute to noise. If you have way more flow than needed you might could throttle pump discharge valve(s) as well, but this will drive the operating point further back on the pump curve, increasing head for centrifugal pumps. PipeFlo is a great tool for pressure drop analysis. Hayes MeasureFlow valves are nice non-adjustable valves for balancing... Just make sure they have enough head to work properly and install them in the correct direction. Bell & Gossett makes handy circuit setter valves that are adjustable otherwise.

Water noises are usually "air" noises.

But if you are certain that is not happening, then maybe larger diameter pipes can clow the speed of the water down and reduce noise. Plus "lagging" to insulate the noise more?

"There is always noise audible."

Seems like everybody knows how to send pictures to help clarify a problem.

You wrote there's always an audible noise. How about recording and posting it for the CR4 pros to hear?

Zvi

Thanks to all of you for the many replies and good suggestions.

Since you had asked, Zvi, here is a link to the sound file. http://sendvid.com/rgm9l991

It is my son's apartment. He said the sound started with the beginning of the sommer season and the switch from heating to cooling. As there was no change to the installation itself it is very likely that the water pressure has increased from the warm water supply for heating. Would warm water be more docile? :-) Notice that the sound stops when flow is stopped which would point to a local issue and not to sound generated by the equipment of the water supply.

The building services personnel suggested to have a professional look after the sound issue as it has nothing to do with the building. In other words they put the onus on the tenant which looks to be a cop-out to me, deflecting responsibility.

We will look for more suggestions but a plumber or engineering consultant would likely be just as puzzled and would look to the water supply as culprit is my guess.

"... it has nothing to do with the building."

Has any other tenant noted the noise in his/her apartment?

If so it would seem that the building owner is responsible for any corrections.

Floram,

Yes, I think you're correct in assuming that the water pressure is greater in summer (cooling) than in winter (heating). Evidently the water flow rate for cooling is higher than for heating. Could be there are different pumps: Cooling pump works with the chiller, heating pump with the HW boiler. Just a guess.

In any case, I believe the source of the noise is from the electric control valve seen at bottom, left of your son's video. This valve probably is controlled by a wall or return air thermostat to maintain steady temperature in the room. Since it's a control device, it well may have a small orifice and that will account for the screeching noise you hear when water the flows.

My advice is to reduce the excess flow rate by partially closing one or both of the quarter-turn ball valves with the green knobs until the noise is bearable. This should not have a significant effect on the unit's cooling capacity. You may have to reopen the valves for winter heating mode.

Good luck,

Zvi

Floram,

Good video! I would have preferred to see at which point the flow starts & the noise starts but it is nearly simultaneous.

This is the sound of too high a CW flow velocity through your unit.

Zvi is nearly there.

That is most likely a PSI or Temp. sensor (or both) as it is quite compact for a motorized valve assy. Unless this device uses a resistance heater to operate a small hydraulic actuator to open/close the valve port (TACO had such a valve we used on hydronic systems way back when).In this case the valve operation could be suspect (V or A too low?).

This may simply be a case of poor engineering re: system flow distribution or more likely a system repair gone wrong.

ie: Not enough CW to the top of the facility...

"We Need A Bigger Pump", instead of bleeding sytem of air & pressurizing correctly.

Removing or altering settings to branch line flow control valve(s).

Incorrectly sized coil unit.Possibly meant to be operated with additional zone jointly.

Installing larger diameter flex lines may help if these are not original.In the case of a 'system' issue the lines won't be of any help & may enhance the problem.Prolly the simplest thing for you to try though.

HTH

Jay

I'd take a close look at the way the pipes are secured. The hangers could be loose, worn or too far apart to properly support the pipes and harmonics and/or vibration could be the cause. A few strategically placed elastomer type couplings may help if vibration is the issue.

Contact "Ask This Old House". They have dealt with a lot of radiator systems.

For your situation, the clatter happens when you turn your fixture ON and it's originating from "some place in the dividers." Based on these two components, I'll derive that when the spigot is turned on, the development of the water going through the lines is rattling a channel some place – a funnel that has relaxed from a strap that once held it solidly set up. A free pipe is the commotion guilty party! Be that as it may, of course… it could be air in the water framework. On the other hand is it something else completely, similar to water hammer?!

Have somebody kill the water on keeping in mind you attempt to distinguish precisely where the sound is originating from. Test both the hot and icy water from the fixture.

When you find the slamming channel, ideally it will be uncovered (like in the storm cellar or crawlspace). Secure the funnel by including a little bit of froth or elastic channel protection to the channel and re-strap it.

On the off chance that the slamming funnel is behind a divider and can't be gotten to, there's very little you can manage without opening up the divider. You can attempt to wedge cushioning or wrap protection at every point the channel rises up out of behind the divider or at close off valves.