This very old thread seems to periodically get revitalised. I suspect a lot
of people do not understand the difference between flow rate and pressure.
You can often see an initial high pressure spurt if you just close down
the tap a bit but from what I've been told pressure reducers do not have
this pressure build up issue. However thus far despite our pressure being
quite high, nothing has been damaged, though you can clearly hear the
initial spurt when the washing machine solenoid valve initially opens.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
wrote in message
...
On Sunday, December 6, 2009 at 9:53:08 PM UTC, Phil L wrote:
Vortex5 wrote:
"Tim W" wrote in message
...
Ron Lowe
wibbled on Sunday 06 December 2009 19:46

Vortex5 wrote:
Today I measured my incoming mains water pressure to be a little
over 10 bar. About 145 PSI. About 100 metres "head"

Quite honestly I was surprised because instinctively I would have
expected it to be somewhat lower. What is normal though? Is 10
bar unusual?

It's never especially bothered me because I have an IMI pressure
regulator taking the in-house pressure down to about 3
bar....however the regulator started playing up recently causing
the in house static pressure to increase a lot which could be
quite alarming when filling a kettle.

The regulator is now fixed....and I am just curious.

That's high.

Normal is around 3-4 bar, but I've seen as high as 7. I've never
seen 10.


Yes. 4+/- bar is quite common. Mine is 7.5bar, limited to 5 bar by
regulator. 7.5 bar is pretty crazy - couldn't imagine what 10 would
be like.

Without a regulator, that would be right at the limit for a lot of
equipment.

--
Tim Watts

This space intentionally left blank...


Some years ago I recall measuring the pressure at about 8 bar, but
have lost the pressure gauge.

This measurement was taken with a brand new "monument tools" gauge I
purchased recently.

I originally installed the regulator after fitting a segment of Hep2O
internally and was uncomfortable about such high pressures with
plastic (incidentally Hep2O is rated to at least 12 Bar safe pressure
at room temp so I was being paranoid).

I'm going to borrow another pressure gauge just to be sure I don't
have dodgy equipment! Will also call the waterco to see what they
have to say.

They'll tell you to turn the pressure down by partially closing the
stoptap,
which is what you should have done before buying a regulator.

--
Phil L
RSRL Tipster Of The Year 2008

This is a common misconception, partially closing a stopcock down has no
bearing on the water pressure, all it does is slow the flow rate down, to
reduce pressure you need a pressure reducing valve set at the desired
pressure on the draw of side.