I suspect that the "flush it several more times" holds the key.
There may be something at the flapper valve face, including
a possible too-long chain. When the flush handle is not being
pressed, the chain from the lever arm to the rubber flapper
in the tank should not sag much, or a link from it could lay
down on the spot the flapper is trying to cover.
Go to Home Depot, find a plumbing sales attendant, and
ask for a training session in Toiletology.


Doug Miller wrote in message
...
In article ,
(Patscga) wrote:
That's me. I have a toilet that makes a "Shhhhh" sound every ten or
fifteen
minutes after it's been flushed. The only way I can get it to stop is to
flush
it several more times. Do I need a plumber?
Thanks for any input.

Probably, the flapper valve at the bottom of the tank is leaking water
because
it is worn, and doesn't seal properly any more. The sound you hear is the
fill
valve opening to let more water into the tank to replace what's leaking
past
the flapper valve. Flushing the toilet opens the flapper valve; if you do
this
a few times, chances are that sooner or later it will seat a little better
and
not leak, which is why you're able to stop the noise that way.

Flapper valves are available at any hardware store for about five dollars,
and
usually can be replaced in five minutes without tools. Most of them even
have
instructions on the package. It's not rocket science. Just remember to
turn
the water off to the toilet before you begin.