Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

Tia,
Deano

--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

Dean Heighington wrote:
Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

Tia,
Deano

Head of water is simply what it says. It will not be improved by the
number of tanks. It is the vertical distance between the top of the
water in the tank(s) and the point of delivery - your mixer.

1 bar is about 10 metre head. You wont get that by messing with tanks!

The sort of mixers you are looking at are designed for pressurized water
systems not gravity feed that you have.
Stick to either simple taps or a mixed specifically designed for gravity
feed plumbing.

ps It does not matter where you cylinder is fitted.

Bob

On 13/09/2011 09:38, Dean Heighington wrote:
Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

You get a bar of pressure for every 30' of head approximately... So the
trick to successful use of low pressure sources, is 22mm pipe, swept
bends (ans as few as possible) and short runs - feeding taps etc
designed for low pressure (many are not).

One tank will possibly provide a little more head - but quite possibly
only a few inches. Raising it will not usually get you much pressure in
absolute terms, but it might make a difference to an upstairs tap which,
when you think about it, might only have 7' of head. You could
potentially double that with careful tank positioning.

The other options are of course to go for mains pressure (or close to
it) hot water systems. That means decent mains cold flow rate, and
either a combi boiler, a heat bank, or an unvented cylinder.


Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

Taps designed for low pressure will perform very much better than ones
that are not. But they still depend on other aspects of the system being
well implemented to reap the best rewards.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article 2081684119337595364.843685d.heighington-
,
says...

Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

You could always switch to a combi and completely remove the need for
header tanks!

It seems to be a regular problem these days. Many taps on sale in the UK
today are manufactured abroad where few countries have antiquated
gravity feed systems. Consequently they do not work well with our
system.

We had our kitchen facelifted some years ago and had a single lever
mixer tap fitted. Cold supply, which was mains fed, was fine - but hot
flow was abysmal. Two years ago we switched to a combi and now flow from
both hot and cold is fine.


--
Kev

Justice? You get justice in the next world,
in this world you have the law...
William Gaddis

John Rumm wrote:

You get a bar of pressure for every 30' of head approximately... So the
trick to successful use of low pressure sources, is 22mm pipe, swept
bends (ans as few as possible) and short runs - feeding taps etc designed
for low pressure (many are not).

One tank will possibly provide a little more head - but quite possibly
only a few inches. Raising it will not usually get you much pressure in
absolute terms, but it might make a difference to an upstairs tap which,
when you think about it, might only have 7' of head. You could
potentially double that with careful tank positioning.

The other options are of course to go for mains pressure (or close to it)
hot water systems. That means decent mains cold flow rate, and either a
combi boiler, a heat bank, or an unvented cylinder.

Taps designed for low pressure will perform very much better than ones
that are not. But they still depend on other aspects of the system being
well implemented to reap the best rewards.

Thanks guys, pretty much what I expected.
I am getting 1/2bar at each outlet which IIUC is the minimum required by
the Bristan if the 1bar they specify is combined across the 2 feeds, and
it's crap, so they should up this in their literature! The alternative is
an Ultra brand tap that requires only 1/2bar and that IS combined (I asked
this time). So I need to check if the centres between the tap inlets are
the same as the existing first, or should I consider two separate wall
mounted single taps? Anyone seem these anywhere?

I wish I was able to put a pump in but that's beyond the budget! And btw...
Anyone want a Bristan wall mounted tap? Going cheap!!!

Thanks
D

--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

"Ret." wrote in message
...
In article 2081684119337595364.843685d.heighington-
,
says...

Two small CWS tanks in loft connected to each other, rather than one
large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined
from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About
as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

You could always switch to a combi and completely remove the need for
header tanks!

It seems to be a regular problem these days. Many taps on sale in the UK
today are manufactured abroad where few countries have antiquated
gravity feed systems. Consequently they do not work well with our
system.

We had our kitchen facelifted some years ago and had a single lever
mixer tap fitted. Cold supply, which was mains fed, was fine - but hot
flow was abysmal. Two years ago we switched to a combi and now flow from
both hot and cold is fine.


you could also check the top & bottom connections of your cylinder, as these
often get scaled up
and restrict the flow to the taps

Dean Heighington wrote:
Two small CWS tanks in loft connected to each other, rather than one
large one. Cylinder on ground floor. Getting very poor flow from wall
mounted bath filler mixer tap - Bristan brand, requires 1bar pressure
combined from hot and cold feeds. About to measure that today and
have sourced an alternative brand that only requires 1/2bar. Other
than installing a pump (which would now mean ALL outlets in bathroom
would be pumped) what else could I do to increase the head of
pressure? Raise tanks in loft? About as much work/cost as installing
a pump. Does a single tank provide more head than 2 connected smaller
tanks?

Looking for options with changing the mixer being the simplest but
still doesn't improve pressure.

Tia,
Deano

Is there any reason why you can't get a new water main connected?

"polly filler" wrote:
"Ret." wrote in message
...

you could also check the top & bottom connections of your cylinder, as these
often get scaled up
and restrict the flow to the taps

Yeah, that was crossing my mind at some point or even the whole cylinder
scaled up cos the water at this local is notoriously hard, but the cylinder
and boiler are fairly recent by the looks of things. I can only imagine bad
pipe runs with lots of 90s cos draining the CWS and refilling resulted in
air locks to both hot and cold feeds. The outlets from the CWS are 1" hot
and 3/4" cold so something has been done downstream.

Low pressure mixer coming tomorrow and plumb counter are prepared to take
back the Bristan because the pressure meets their min spec but does not
perform well.

Will keep you posted

--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

"Phil L" wrote:

Is there any reason why you can't get a new water main connected?

It's a gravity fed system. The rising main feed to the CWS tank is not an
issue. Have you misunderstood? Or have I

--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

On Sep 13, 9:38*am, Dean Heighington
wrote:
Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

Tia,
Deano

--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

The probable reason for two tanks is related to the size of the
trapdoor to your loft. ie the tank has been changed in thepast. The
idea is that there is enough water to fill a bath in it/them, 40
gallons was the norm.
The system often works better than the current craze for mains
pressure systems. Provided the right sized taps/valves and pipework is
fitted that is..

On Sep 13, 10:10*am, "Ret." wrote:
In article 2081684119337595364.843685d.heighington-
,
says...



Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

You could always switch to a combi and completely remove the need for
header tanks!

It seems to be a regular problem these days. Many taps on sale in the UK
today are manufactured abroad where few countries have antiquated
gravity feed systems. Consequently they do not work well with our
system.

We had our kitchen facelifted some years ago and had a single lever
mixer tap fitted. Cold supply, which was mains fed, was fine - but hot
flow was abysmal. Two years ago we switched to a combi and now flow from
both hot and cold is fine.

--
Kev

Justice? You get justice in the next world,
in this world you have the law...
William Gaddis

Our "antiquated system" is far more reliable than combi boilers, which
are the spawn of satan.

harry wrote:

Our "antiquated system" is far more reliable than combi boilers, which
are the spawn of satan.

I either heard this somewhere or made it up myself ...

Do we have cold water storage in our lofts because if the blitz? On the
basis that bombing meant Water mains supply could be disrupted to 100/0s
of homes and having ones own store of water meant toilets could be flushed,
water boiled, hands washed and in the event of a direct hit, fires could be
put out by the release of gallons of water from above, in an instant!

Or is this post-rationalisation?




--
What else are opposable thumbs for? Get to me at
masterfix{at}btinternet{dot}com

On 13/09/2011 19:32, harry wrote:
On Sep 13, 10:10 am, wrote:
In article2081684119337595364.843685d.heighington-
,
says...



Two small CWS tanks in loft connected to each other, rather than one large
one. Cylinder on ground floor. Getting very poor flow from wall mounted
bath filler mixer tap - Bristan brand, requires 1bar pressure combined from
hot and cold feeds. About to measure that today and have sourced an
alternative brand that only requires 1/2bar. Other than installing a pump
(which would now mean ALL outlets in bathroom would be pumped) what else
could I do to increase the head of pressure? Raise tanks in loft? About as
much work/cost as installing a pump. Does a single tank provide more head
than 2 connected smaller tanks?

Looking for options with changing the mixer being the simplest but still
doesn't improve pressure.

You could always switch to a combi and completely remove the need for
header tanks!

It seems to be a regular problem these days. Many taps on sale in the UK
today are manufactured abroad where few countries have antiquated
gravity feed systems. Consequently they do not work well with our
system.

We had our kitchen facelifted some years ago and had a single lever
mixer tap fitted. Cold supply, which was mains fed, was fine - but hot
flow was abysmal. Two years ago we switched to a combi and now flow from
both hot and cold is fine.

--
Kev

Justice? You get justice in the next world,
in this world you have the law...
William Gaddis

Our "antiquated system" is far more reliable than combi boilers, which
are the spawn of satan.

He was complaining of poor performance, not reliability!

There are other ways of getting mains pressure hot water without having
a combi anyway.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/