"Whirring" noise after toilet is flushed and water is being refilled in tank

[gotaigo]

Hi all,

I've been hearing this "whirring" noise after we flush the 1st floor (main) toilet when the refill valve is refilling the toilet. The noise ceases once the tank has filled. Assuming that it could be anywhere from the shutoff valve to the refill valve, I replaced both. Unfortunately, that did not solve the problem.

What's interesting or weird is that the noise can be triggered from the two upstairs (2nd floor) toilets as well although it seems to be the loudest and consistent from the 1st floor bathroom. I thought it was only isolated to the 1st floor toilet, but I must admit that I did hear that same "whirring" noise after the 2nd floor toilet was flushed even though with those toilets I can't seem to replicate as consistently as the original 1st floor toilet. I had a feeling it might not be the shutoff valve or refill valve that was the culprit after noticing that even on occasions and to a lesser degree (noise wise), the 2nd floor toilets were also triggering this noise. But it definitely is the loudest and most consistent from the 1st floor toilet.

Please help! What could be causing this all of a sudden?

Thanks in advance.

 

[House Doc]

I've seen (heard) this before. Is the shut-off, at the wall completely open?
Take the top of the tank off and put your fingers on top of the ballcock (fill valve), The valve that allows the water into the tank and flush. If it's "whistling" and you can "feel" it it's probably in the ballcock. If not it's in the supply valve (wall). I recommend the "Fluidmaster" brand fill valve.
Whenever you post a problem here try and include whatever photos that might be relevant .

 

[gotaigo]

Hi Doc,

I heard that having the shutoff valve is one of the more popular solution to this problem but not in my case. I had all toilets short of fully open, but I did go ahead and they are all now fully open. Right before I fully opened the 2nd floors shutoff valve, I flushed it and I heard the noise coming from the 1st floor toilet area, most likely the pipe attached to the shutoff valve from that bathroom. I'm beginning to think that the "bottle neck" is in the 1st floor bathroom piping as the noise was emanating form there although I flushed from the 2nd floor bathroom.

I'm beginning to suspect that the problem is coming from the 1st floor bathroom shutoff area as I've stated earlier, the shutoff valve as well as the refill valve in that toilet. Whether I use that toilet or the one upstairs, the sound is emanating from the 1st floor bathroom. And, yes, it is a Fluidmaster.

This might be above my payscale as a DIYer. What could be possibly causing this noise? Do plumbers use the same path of copper piping for all the toilets throughout the house for the incoming water supply? Is the scenario of a narrowing of the copper piping somewhere that's feeding the supply line to the toilets? If that's the case, is the remedy to replace that part of the piping? If so, how much does this sort of thing cost for a plumber to do?
I hope there's still a easier or DIYer solution for my problem.

 

[Geofd]

have you replaced the 2 upstairs fill valves???? the fluid masters have colored (nozzles)??? that clip onto the fill valves each color is for a particular brand.....you could try a nozzle with a slower fill the directions will tell you which fills faster or slower