We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Phil L"
saying something like:

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.

Utter ********.

Doctor Drivel
wibbled on Monday 07 December 2009 17:20


"Tim W" wrote in message
...
ARWadsworth
wibbled on Monday 07 December 2009 10:04


"Tim W" wrote in message

Not a plantpot then?

--
Tim Watts


It depends what page his Ladybird Book Of Insults is randomly opened to.

Adam

Ah, the book with 3 pages:

Plantpot
Idiot
And something about blokes in dresses...

You fill all three.

If you've been fantacising about big blokes with hairy beards, in dresses,
you really do need help.

Or a Norwegian fisherman.

--
Tim Watts

This space intentionally left blank...

On Mon, 07 Dec 2009 17:21:04 +0000, Doctor Drivel wrote:
It depends what page his Ladybird Book Of Insults is randomly opened to.

And which pages haven't been chewed (or otherwise soiled).

Another pervo that needs tagging.

*cheers*

"Jules" wrote in message
news
On Mon, 07 Dec 2009 17:21:04 +0000, Doctor Drivel wrote:
It depends what page his Ladybird Book Of Insults is randomly opened
to.

And which pages haven't been chewed (or otherwise soiled).

Another pervo that needs tagging.

*cheers*

Must have 4 pages in the book :-)

Adam

"Doctor Drivel" wrote in message
...

"ARWadsworth" wrote in message
m...

"Tim W" wrote in message
...
Doctor Drivel
wibbled on Monday 07 December 2009 00:42


"Tim W" wrote in message
...
Doctor Drivel
wibbled on Monday 07 December 2009 00:29


"Phil L" wrote in message
m...

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.

The static presure will burst equiment not rated to 10 bar. You NEED
a
PRV.

Sometimes the man speaks sense - and this is one such occasion

You are an idiot!

Not a plantpot then?

It depends what page his Ladybird Book Of Insults is randomly opened to.

You need tagging.


What with?

Adam

In message , Tim W
writes
ARWadsworth
wibbled on Monday 07 December 2009 10:04


"Tim W" wrote in message

Not a plantpot then?

--
Tim Watts


It depends what page his Ladybird Book Of Insults is randomly opened to.

Adam

Ah, the book with 3 pages:

Plantpot
Idiot
And something about blokes in dresses...

Yes, the pratt can't tell the difference between a dress and a sarong

http://www.kateda.org/Kateda.org/Home.html


--
geoff

ARWadsworth wrote:

"Jules" wrote in message
news
On Mon, 07 Dec 2009 17:21:04 +0000, Doctor Drivel wrote:
It depends what page his Ladybird Book Of Insults is randomly
opened to.

And which pages haven't been chewed (or otherwise soiled).

Another pervo that needs tagging.

*cheers*

Must have 4 pages in the book :-)

Adam, FFS I am trying to have a night cap here and my key board does not
like the spray. It copes, but it takes a week out of the shower to dry out.

Dave

Tim W wrote:
Dave
wibbled on Monday 07 December 2009 16:46

Doctor Drivel wrote:
"Tim W" wrote in message
...
Doctor Drivel
wibbled on Monday 07 December 2009 00:29

"Phil L" wrote in message
m...

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.
The static presure will burst equiment not rated to 10 bar. You NEED a
PRV.
Sometimes the man speaks sense - and this is one such occasion
You are an idiot!
Where does that rank against being called a plant pot then?

Well, I feel aggrieved. Not special enough to get a proper name.

Have you noticed Drivel's creativity is down the pan of late. Must be the
new pills...


Horse tranquillisers?

Dave

On Mon, 07 Dec 2009 19:20:03 +0000, ARWadsworth wrote:
Must have 4 pages in the book :-)

Ha! Doubtless a big potted Aspidistra on the front cover, too...

"Tim W" wrote in message
...
Doctor Drivel
wibbled on Monday 07 December 2009 17:20


"Tim W" wrote in message
...
ARWadsworth
wibbled on Monday 07 December 2009 10:04


"Tim W" wrote in message

Not a plantpot then?

--
Tim Watts


It depends what page his Ladybird Book Of Insults is randomly opened
to.

Adam

Ah, the book with 3 pages:

Plantpot
Idiot
And something about blokes in dresses...

You fill all three.

If you've been fantacising about big blokes with hairy beards, in dresses,
you really do need help.

Or a Norwegian fisherman.

Help? So you help people get these blokes.
This one needs tagging.

"geoff" wrote in message
...
In message , Tim W
writes
ARWadsworth
wibbled on Monday 07 December 2009 10:04


"Tim W" wrote in message

Not a plantpot then?

--
Tim Watts


It depends what page his Ladybird Book Of Insults is randomly opened to.

Adam

Ah, the book with 3 pages:

Plantpot
Idiot
And something about blokes in dresses...

Yes, the pratt can't tell the difference between a dress and a sarong

http://www.kateda.org/Kateda.org/Home.html

Fantastic Maxie. You are half naked resplendent in a flock! What a man!!!

Doctor Drivel
wibbled on Tuesday 08 December 2009 01:04


"geoff" wrote in message

Yes, the pratt can't tell the difference between a dress and a sarong

http://www.kateda.org/Kateda.org/Home.html

Fantastic Maxie. You are half naked resplendent in a flock! What a
man!!!

Now run along and get some kleenex and tell nursie you need new sheets...

--
Tim Watts

This space intentionally left blank...

"Tim W" wrote in message
...
Doctor Drivel
wibbled on Tuesday 08 December 2009 01:04


"geoff" wrote in message

Yes, the pratt can't tell the difference between a dress and a sarong

http://www.kateda.org/Kateda.org/Home.html

Fantastic Maxie. You are half naked resplendent in a frock! What a
man!!!

Now run along and get some kleenex and tell nursie you need new sheets...

You are right, Maxie may need these things. What a man! And he plays in a
Paddy band dressed like that as well.

"Doctor Drivel" wrote in message
...

"Tim W" wrote in message
...
Doctor Drivel
wibbled on Tuesday 08 December 2009 01:04


"geoff" wrote in message

Yes, the pratt can't tell the difference between a dress and a sarong

http://www.kateda.org/Kateda.org/Home.html

Fantastic Maxie. You are half naked resplendent in a frock! What a
man!!!

Now run along and get some kleenex and tell nursie you need new sheets...

You are right, Maxie may need these things. What a man! And he plays in
a Paddy band dressed like that as well.

He made a song for you

http://www.youtube.com/watch?v=j72-_iF8F4Y&feature=PlayList&p=BC74A1405DCDB78D&index= 40

Adam

On 6 Dec, 19:44, "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.

Well the taps I just bought are rated up to 6 bar so I'd certainly
have trouble. You include a turbine on the incoming mains to generates
a bit of electricity everytime you use the taps.

Matt

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

Very high. High enough to burst a defective hot water cylinder and LD
polyethylene pipe. Is the reservoir on a hill nearby or does the
council keep the pressure high by pumping? 5 or 6 bar is much more
reasonable.



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.

Is that what we call an Ajax valve?

R

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

Vortex5 wrote:

wrote in message
...
Just another thought:
Turning the supply valve or tap down isn't really a solution if the
pressure is as high as you suggest.
Clamping down a valve may reduce the flow but it won't change the
pressure. When the flow stabilises, the pressure will be the same.
It's a bit like volts and amps. "Volts is pressure, Amps is flow"

Please no flames...... the OT has a pressure (volts) problem not a
flow (amps) problem so squeezing the flow won't help.

I remain curious about the pressure/head being reported in the
original post. I suspect that most providers in UK don't supply water
much above 3, 4 or 5 bar.

EP

What really confuses me is that there are plenty of houses around me on
higher land, none are more than about 20 metres ( - 2 bars) higher.

I could understand if pressure was (say) 5 bar, but cannot understand
why I see 10. hence the original post.

As I said previously first stop is to double-check the instrument. I'm
wondering if I can bodge up a connection to do this pneumatically at the
local garage.

Get some hose. Fit a tyre valve at one end and connect the other to the
tap. Make sure that the hose is vertical and full of air. Turn on the
tap and measure the pressure with tyre pressure gauge.

R

js.b1 wrote:
On Dec 6, 10:17 pm, "
wrote:
Please no flames...... the OT has a pressure (volts) problem not a
flow (amps) problem so squeezing the flow won't help.

Correct.

I remain curious about the pressure/head being reported in the
original post. I suspect that most providers in UK don't supply
water much above 3, 4 or 5 bar.

That's the typical range.

Water co's do play about with pressure, if works are undertaken they
drop it down noticeably, then ramp it back up once complete. The
problem with 10 bar is water hammer (flexible w/machine hoses) is
going to get brutal on the pipework.

Water hammer occurs when flow is shut down suddenly. The water is not
compressible and has inertia. I believe that uPVC pipe has a safety
factor of at least 2 to protect against water hammer.

R

"ARWadsworth" wrote in message
m...

You are right, Maxie may need these things. What a man! And he plays
in a Paddy band dressed like that as well.

He made a song for you

http://www.youtube.com/watch?v=j72-_iF8F4Y&feature=PlayList&p=BC74A1405DCDB78D&index= 40

Fantastic. I bet Maxie sings that song on the beach in the Far East up the
tree in that frock. What a man! Truly fantastic. Such a foot tapping tune
as well. Only Maxie can do that.

On Wed, 09 Dec 2009 10:23:30 +1300, Roger Dewhurst wrote:


Get some hose.
ok - how long (high) is required for the vertical air-filled bit?

Fit a tyre valve at one end
Not sure how to do this?


--
Geo

On Wed, 09 Dec 2009 15:55:33 GMT, Geo
wrote:

On Wed, 09 Dec 2009 10:23:30 +1300, Roger Dewhurst wrote:


Get some hose.
ok - how long (high) is required for the vertical air-filled bit?

Fit a tyre valve at one end
Not sure how to do this?

Ingenuity...


This _is_ a diy group :-)

--
Frank Erskine

On Wed, 09 Dec 2009 16:21:06 +0000, Frank Erskine
wrote:

On Wed, 09 Dec 2009 15:55:33 GMT, Geo
wrote:

On Wed, 09 Dec 2009 10:23:30 +1300, Roger Dewhurst wrote:


Get some hose.
ok - how long (high) is required for the vertical air-filled bit?

Fit a tyre valve at one end
Not sure how to do this?

Ingenuity...


This _is_ a diy group :-)

Yebbut - I wasn't sure if the duct tape would hold...

--
Geo

Domestic mains pressure depends on where you live how many houses it has to serve and how tall the buildings are. Example on a main road in London you would expect the main pressure to be 10 bar or so, but in very remote places you should expect low pressure e.g. in the lake district where there is very little housing for miles apart. You Should expect about 3 bar pressure in some remote areas. Most domestic taps and boilers can run off 1 bar pressure, but if you had a house three stories high then this would not be enough pressure and your water will come out at a drisel or not at all on the top floor. 10 bar mains pressure is pretty standard now. Just imagine all your neighbours getting up at 7 in the morning all wanting a shower at the same time? That is a large demand on supply! You may even notice that a some parts of the day you have better pressure than other times of the day depending on the demand on the supply.

wrote:
10 bar mains pressure is pretty standard now.

Bravo on waiting 7 years to spout ********.

Tim

--
Trolls and troll feeders go in my killfile

On 08/07/2016 15:30, Tim+ wrote:
wrote:
10 bar mains pressure is pretty standard now.

Bravo on waiting 7 years to spout ********.

Tim


Quite. Even after they replace Victorian mains in London they don't
supply anything like 10 bar - and a good job too given there are still
very many iron/lead communication/supply pipes.

And nice pun. Pity we can't apply 10 bar to his ********/her tits.

--
Robin
reply-to address is (intended to be) valid

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.

On Fri, 05 Aug 2016 13:51:25 -0700, steviehtcck wrote:

On Sunday, December 6, 2009 at 9:53:08 PM UTC, Phil L wrote:

Did you miss ^^^^^^^^ ^ ^^^^ that bit? The post is nearly 7 years old!

--
TOJ.

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.

Here in Palm Desert California our home was built with TWO water pressure regulators. One for the house supply (set at 50psi) and one for the garden sprinkler supply. I have never bothered to determine the latter pressure. Static pressure from the street is 95psi which varies but not by much.
Construction methods here involve a cast concrete slab with the water pipes set in the concrete. To me, this is BLOODY LUNACY as anyone knows concrete flexes and cracks. Slab leaks are not at all uncommon. Guess why?

On 04/08/2018 19:00, wrote:
Here in Palm Desert California our home was built with TWO water pressure regulators. One for the house supply (set at 50psi) and one for the garden sprinkler supply. I have never bothered to determine the latter pressure. Static pressure from the street is 95psi which varies but not by much.
Construction methods here involve a cast concrete slab with the water pipes set in the concrete. To me, this is BLOODY LUNACY as anyone knows concrete flexes and cracks. Slab leaks are not at all uncommon. Guess why?

This being a UK group, we are not particularly interested.

Yes well thinking ahead has never been a strong point of builders anywhere
in the world when it affects their bottom line profit.
Brian

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

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
Here in Palm Desert California our home was built with TWO water pressure
regulators. One for the house supply (set at 50psi) and one for the garden
sprinkler supply. I have never bothered to determine the latter pressure.
Static pressure from the street is 95psi which varies but not by much.
Construction methods here involve a cast concrete slab with the water pipes
set in the concrete. To me, this is BLOODY LUNACY as anyone knows concrete
flexes and cracks. Slab leaks are not at all uncommon. Guess why?

wrote:
On Sunday, 6 December 2009 21:53:08 UTC, Phil L wrote:

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

Turning the stop tap down does not reduce the static pressure - sure it
will reduce the flow and consequentially the running pressure, but as
soon as you stop demand, even with the stop cock reduced to a minute pin
hole, the standing pressure is exactly the same as the main line pressure
- I would have thought it to be obvious to an expert


But you dont have to be an expert to spot that youre responding to 9
year old post. I think the problem may well have been resolved by now.

Tim


--
Please don't feed the trolls

On Sunday, 6 December 2009 19:44:27 UTC, 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.

The water companies have a statutory minimum pressure they have to deliver. They should also have a statutory maximum of 4 bars. 4.5 is the rated working limit for many central heating boilers etc. Above that will damage them.. A fitting blew off the mains supply in my mothers flat at somewhere between 7 and 11 bars. Three flats uninhabitable for 18 months and £200k insurance bill. No liability to the water company. Partially closing the main supply valve reduces flow, (and make noise) but does nothing to reduce pressure. You need a reducer on the system if it is above 4 bars. The big step down valves on the water mains they install now are not fail safe and have a habit of failing by giving full pressure - 11 bars etc. Not good for your system. The design rating of copper pipe is 12 bars but the fittings etc are your weak point. If your system is going to see over 4 bars it needs to be properly pressure tested and certified to take max pressure + 20%. This countries standards are so bad it makes me weep, (my pipework as well).

On Thu, 04 Apr 2019 10:41:18 -0700, whitwp wrote:

On Sunday, 6 December 2009 19:44:27 UTC, Vortex5 wrote

Did you miss this ^^^^^^^^^^^ ? Over 9 years ago.

--
TOJ.

I wonder how many pipes have failed due to high pressure in the 10 years
since the post replied to here?
Brian

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

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
On Sunday, 6 December 2009 19:44:27 UTC, 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.

The water companies have a statutory minimum pressure they have to deliver.
They should also have a statutory maximum of 4 bars. 4.5 is the rated
working limit for many central heating boilers etc. Above that will damage
them. A fitting blew off the mains supply in my mothers flat at somewhere
between 7 and 11 bars. Three flats uninhabitable for 18 months and £200k
insurance bill. No liability to the water company. Partially closing the
main supply valve reduces flow, (and make noise) but does nothing to reduce
pressure. You need a reducer on the system if it is above 4 bars. The big
step down valves on the water mains they install now are not fail safe and
have a habit of failing by giving full pressure - 11 bars etc. Not good for
your system. The design rating of copper pipe is 12 bars but the fittings
etc are your weak point. If your system is going to see over 4 bars it needs
to be properly pressure tested and certified to take max pressure + 20%.
This countries standards are so bad it makes me weep, (my pipework as well).

On 04/04/2019 18:41, wrote:


The water companies have a statutory minimum pressure they have to deliver. They should also have a statutory maximum of 4 bars. 4.5 is the rated working limit for many central heating boilers etc. Above that will damage them. A fitting blew off the mains supply in my mothers flat at somewhere between 7 and 11 bars. Three flats uninhabitable for 18 months and £200k insurance bill. No liability to the water company. Partially closing the main supply valve reduces flow, (and make noise) but does nothing to reduce pressure. You need a reducer on the system if it is above 4 bars. The big step down valves on the water mains they install now are not fail safe and have a habit of failing by giving full pressure - 11 bars etc. Not good for your system. The design rating of copper pipe is 12 bars but the fittings etc are your weak point. If your system is going to see over 4 bars it needs to be properly pressure tested and certified to take max pressure + 20%. This countries standards are so bad it makes me weep, (my pipework as well).



4 bar is for the sealed system. Mains pressure can be higher than that.

A pressure regulator only really works with a flow through it. The
static pressure (when no flow) will always be higher than the set point
(although not necessarily the fill input pressure - that depends on the
volume of pipework downstream). The downstream plumbing must be able to
handle the static pressure, not just the regulators set point pressure.

--
Andrew

On 05/04/2019 10:09, Andrew Gabriel wrote:
On 04/04/2019 18:41, wrote:

The water companies have a statutory minimum pressure they have to
deliver. They should also have a statutory maximum of 4 bars. 4.5 is
the rated working limit for many central heating boilers etc. Above
that will damage them. A fitting blew off the mains supply in my
mothers flat at somewhere between 7 and 11 bars. Three flats
uninhabitable for 18 months and £200k insurance bill. No liability to
the water company. Partially closing the main supply valve reduces
flow, (and make noise) but does nothing to reduce pressure. You need a
reducer on the system if it is above 4 bars. The big step down valves
on the water mains they install now are not fail safe and have a habit
of failing by giving full pressure - 11 bars etc. Not good for your
system. The design rating of copper pipe is 12 bars but the fittings
etc are your weak point. If your system is going to see over 4 bars it
needs to be properly pressure tested and certified to take max
pressure + 20%. This countries standards are so bad it makes me weep,
(my pipework as well).


4 bar is for the sealed system. Mains pressure can be higher than that.

A pressure regulator only really works with a flow through it.

Not so.

The
static pressure (when no flow) will always be higher than the set point
(although not necessarily the fill input pressure - that depends on the
volume of pipework downstream). The downstream plumbing must be able to
handle the static pressure, not just the regulators set point pressure.

That is just plain WRONG.

For example as I found out recently my mains pressure HW cylinder has a
regulator on the input. When the pressure rises above 2.1 bar it shuts
off flow into the tank completely. There is an air bubble pressure
maintainer so that there is 'elasticity' in the system.

The valve on your loo shuts off input completely. That does not mean the
cistern is at 10 bar!

You are thinking of flow reduction as a means to achieve pressure
reduction. Then what you say applies, but that is not what a proper
pressure reducer does.

--
"Strange as it seems, no amount of learning can cure stupidity, and
higher education positively fortifies it."

- Stephen Vizinczey

On 05/04/2019 11:24, The Natural Philosopher wrote:
On 05/04/2019 10:09, Andrew Gabriel wrote:
On 04/04/2019 18:41, wrote:


A pressure regulator only really works with a flow through it.

Not so.

The static pressure (when no flow) will always be higher than the set
point (although not necessarily the fill input pressure - that depends
on the volume of pipework downstream). The downstream plumbing must be
able to handle the static pressure, not just the regulators set point
pressure.

That is just plain WRONG.

That was my initial thoughts as well, but I think it depends on just how
pedantic he is being

http://www.beswick.com/basics-pressure-regulators

shows the principle of zero flow rate regulators and goes on to define

Lock Up Pressure
€œLockup pressure€� is the pressure above the set-point that is required
to completely shut the regulator valve off and insure that there is no flow.

But I suspect that for domestic plumbing applications the difference
between lock up pressure and set point pressure will be lost in the noise.




For example as I found out recently my mains pressure HW cylinder has a
regulator on the input.Â* When the pressure rises above 2.1 bar it shuts
off flow into the tank completely. There is an air bubble pressure
maintainer so that there is 'elasticity' in the system.

The valve on your loo shuts off input completely. That does not mean the
cistern is at 10 bar!

You are thinking of flow reduction as a means to achieve pressure
reduction. Then what you say applies, but thatÂ* is not what a proper
pressure reducer does.

No I think he is being very pedantic




--
Chris B (News)

I think 3 to 4 bar is better water pressure but it's depend our use water system

On Sunday, December 6, 2009 at 7:44:27 PM UTC, 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.