(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 5 of 5

Thread: Intermittenet problem

  1. #1

    Default Intermittenet problem

    Bought a house about six months ago, had something weird happen a couple of times here recently. A few times when we've flushed the toilets in each of our bathrooms there is thud kind of a noise and when the tank refills it kind of sounds like its spitting out air. Also a few times when we've turn the water on in the kitchen sink the water will start to come on the also act like its spitting out air and then flow normally. Doesn't happen all the time, seems to have happened 3-4 times in the past 3 weeks after the weather has gotten colder. Is this a cause for concern or no big deal? Doesn't happen all the time, just randomly so far.

  2. #2
    DIY Member Mort's Avatar
    Join Date
    Jan 2007


    First of all, I'm not a plumber....though I do employ them from time to time

    In my home, that happens whenever the supply has been turned off at the main and then turned on again after a repair has been completed. Assuming that hasn't been done, then the only variable that I know of would be the pressure regulator valve. Perhaps it's giving up the ghost.


  3. #3
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    New England


    Are you on public water or a well?
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  4. #4


    I'm on public water. I haven't turned off the main water supply. I did however turn the water supply off to the spicket in the backyard.

  5. #5
    DIY Junior Member cc_rider's Avatar
    Join Date
    Dec 2007
    Austin Texas


    Well, here's my marginally-educated guess: the thump after flushing is most likely due to 'water hammer', which can happen whenever there's a sharp change in water pressure, such as flushing a toilet. The fastest/cheapest way to address the issue is to reduce the speed at which your toilet refills, by cranking the supply valve (usually at the wall, near the toilet) closed a little bit. So your toilet takes twice as long to refill, big deal.

    The 'real' way to fix it is to add 'buffers' in the plumbing. Home Desperate sells special fittings, but you may already have something similar. If the plumbing runs through the attic, you're likely to see 'stubs' sticking up here and there, just capped-off pipes. Once upon a time those pipes had a pocket of air inside, and the air acted as a shock absorber to reduce water hammer. The only way to get the air back into them is:
    - Shut off the water to the whole house.
    - Open the faucets and hose bibs to drain the water.
    - Take the caps off the tops of the 'buffer pipes' in the attic.
    - When the buffers have no water in them, put the caps back on tight.
    - Close the faucets and hose bibs.
    - Turn the main water back on.
    - Open the faucets one at a time, to flush the air out of the system.

    Now the 'hissing' sound may be another problem. You could have a leak which is allowing air into the system. It's possible the colder weather caused some shrinkage somewhere, creating a leak. The 'pressure regulator valve' theory sounds equally reasonable, although I'm not sure all houses have one. I've been all under my house and never seen such a thing: I'm pretty sure my water pressure is just whatever the City decides to provide that day...



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts