House water pressure gets super low when toilet is flushed.

Old 11-10-21, 06:05 PM
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House water pressure gets super low when toilet is flushed.

So, recently, over the last 2 weeks or so I've noticed that when a toilet is flushed the house water pressure gets very low.
  • When I'm taking a shower, it seems to affect it no matter what. The hot water and cold water are equally affected. Occasionally the bathtub/shower will make a squealing noise that I can occasionally stop by jiggling the nub thing.
  • Even if no toilets are flushed the shower will usually start off with regular water pressure and then get lower (but not as low as when I flush the toilet).
  • Often all the faucets in the house will be equally affected (hot and cold).
  • Once or twice ive noticed that the hot water will be affected but not the cold (kitchen faucet).
  • Sometimes when I flush a toilet nothing happens (everything is fine).
I'm honestly unsure of what to do at this point. If I have to hire a plumber I wouldnt mind, but if I can figure this out by myself (with your help) that would be great. Thank you!
Old 11-10-21, 08:38 PM
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Welcome to the forums.

Need more helpful information.

City water or well system ?
A city water system could have a pressure regulator valve at the meter area.
How old is the house ?
Older iron pipe gets clogged with rust with age and restricts water flow.
bulova voted this post useful.
Old 11-11-21, 05:29 AM
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>Even if no toilets are flushed the shower will usually start off with regular water pressure and then get lower
An intermittently failing pressure regulator, I'd guess.
Old 11-11-21, 05:55 AM
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Sure sounds like a well or pressure tank issue which can easily effect water pressure throughout the house!
bulova voted this post useful.
Old 11-15-21, 02:22 PM
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Since it's a recent development I would also lean toward a failing pressure reducing valve.
Old 11-25-21, 05:35 AM
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One thing you can do to check for and flush out loose sediment.
One at a time take off shower heads, faucet aerators, etc. Run first the hot water for a minute then the cold water for a minute. Inspect and clean the shower head or strainer before putting it back.

Ideally you would also want to remove the stems and cartridges of faucets and angle stops and shutoffs and flush each for at least 20 seconds to get out sediment caught before each of these.. This part is reserved for experts who can catch the water in a pot or bucket and/orfolded cloth towels before the water hits the ceiling or shoots out past the cabinet doors.
Old 11-26-21, 10:32 AM
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Because it seems to have happened just recently, it most likely isnít this, but just in case - if you have any whole house filters make sure they arenít plugged up. I forget to change mine sometimes and when the water pressure gets really low, I notice it, and then like a scatterbrain I totally forget about the filters and look for other problems. Then I remember, change the filter, and all is well Ė till the next time and I do the same thing again.

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