"local" Transients
"local" Transients
(OP)
I work at a water utility and we have had some customer complaints about noisy pipes. We have done the standard checks, which include inspecting the meter and double checks at their service connection and making sure all line valves are fully open. We also advised them of the possibility of air in their lines or a faulty Pressure Reducing Valve. They claim to have had their system checked by a plumber and everything is supposedly working properly.
In order to go a step beyond the basic checks, I installed a new logger that we are trying by Telog which can monitor for transients and capture impulse data. I attached the logger to a hydrant at the end of their street and got the reading attached to this post. There have been a few instances of this occurrence and one matched up (time wise) to the complaint of pipe noise. This appears to be a local issue, meaning the source is not due to our operations or hydrant testing, etc.
Talking to others internally, there was at least one case where a customers faulty ice maker was causing similar issues for adjacent customers. I found it hard to believe that plumbing issues with one house could be transferred to neighbors, but this might be one of those cases. Does anyone have a similar experience who can offer advice which I can pass on to the customer on how to resolve?
Thanks in advance!
In order to go a step beyond the basic checks, I installed a new logger that we are trying by Telog which can monitor for transients and capture impulse data. I attached the logger to a hydrant at the end of their street and got the reading attached to this post. There have been a few instances of this occurrence and one matched up (time wise) to the complaint of pipe noise. This appears to be a local issue, meaning the source is not due to our operations or hydrant testing, etc.
Talking to others internally, there was at least one case where a customers faulty ice maker was causing similar issues for adjacent customers. I found it hard to believe that plumbing issues with one house could be transferred to neighbors, but this might be one of those cases. Does anyone have a similar experience who can offer advice which I can pass on to the customer on how to resolve?
Thanks in advance!





RE: "local" Transients
RE: "local" Transients
We have also not been exercising valves at these times and its outside of times where the FD would do hydrant tests. I'm at a loss. Maybe I'll look closer at valve operation at the upstream reservoirs and see if something jumps out.
When you installed a recorder on the customers plumbing and then on the hydrant, do you see the disturbance at the hydrant or does the PRV keep the issue within the residence? In other words, does the PRV (or possibly backflow preventer) create a barrier for transients? We only have one logger, but plan to get more. As a side topic, what other ways have you used them to solve real world issues? I'd love ideas on how to maximize the technology.
Thanks for the feedback!
RE: "local" Transients
In my experience, transients are too fast to be effectively filtered by PRVs. A transient in the main passes right through a customer's PRV.
On the other hand, I haven't found any customer caused transients causing problems in the main. In only one instance of interior/exterior monitoring has the exterior recorder even shown a blip corresponding to the interior transient. And that was small enough that I'm sure no other customers could have noticed. I attribute that to the magnitude of the customer's transient.