We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water supplies
which we suspect was due to a problem with our water mains further down the
street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has cleared up
but we continue to intermitently get dirt in our HW supply which I've been
putting down to a HW cyclinder full of silt. If no water has been drawn for
a while (like overnight) the HW is visibly stained.

Today I thought I'd try and drain down the HW tank using the drain cock to
see what the water was like nearer the bottom of the tank (expecting it to
be really dirty). I filled half a bucket and poured it into our sink and
this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I repressurised
and and refilled the sink from the tap with this result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg


What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had a new
pressure vessel about 3 weeks ago after the diaphragm failed in the old one
so I know it's not the pressure vessel that's full of crud.

As I say, our cold supply seems okay but I'd really like to flush all this
crud out of our HW system but I'm mystified why water drained from the
bottom of the tank is so much cleaner than what's coming out the top.

Tim

In article ,
"Tim+" writes:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water supplies
which we suspect was due to a problem with our water mains further down the
street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has cleared up
but we continue to intermitently get dirt in our HW supply which I've been
putting down to a HW cyclinder full of silt. If no water has been drawn for
a while (like overnight) the HW is visibly stained.

Today I thought I'd try and drain down the HW tank using the drain cock to
see what the water was like nearer the bottom of the tank (expecting it to
be really dirty). I filled half a bucket and poured it into our sink and
this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I repressurised
and and refilled the sink from the tap with this result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg


What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had a new
pressure vessel about 3 weeks ago after the diaphragm failed in the old one
so I know it's not the pressure vessel that's full of crud.

As I say, our cold supply seems okay but I'd really like to flush all this
crud out of our HW system but I'm mystified why water drained from the
bottom of the tank is so much cleaner than what's coming out the top.

I'm guessing it is in the bottom, but it wasn't stirred up when
you tried draining from the bottom. Filling just the bottom and
emptying it a few times might do it. Does it have any kind of
access panel such as immersion heater tap that you could look in
when it's drained down (or drained below the access panel)?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Fri, 31 Aug 2012 14:48:17 +0100, Tim+ wrote:
What I want to know is, where the feck is all this crud hiding??

Are you sure the bottom of the tank's not scaled up, with the crap hiding
on top (and the scale acting as a filter when you use the drain tap)? I
attacked ours a couple of years ago after performance started dropping
off, and probably the bottom ten inches or so of the tank was full of
scale.

In article ,
"Tim+" writes:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water supplies
which we suspect was due to a problem with our water mains further down the
street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Reminds me of
http://news.nationalgeographic.com/n...world-science/

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Jules Richardson wrote:
On Fri, 31 Aug 2012 14:48:17 +0100, Tim+ wrote:
What I want to know is, where the feck is all this crud hiding??

Are you sure the bottom of the tank's not scaled up, with the crap
hiding on top (and the scale acting as a filter when you use the
drain tap)? I attacked ours a couple of years ago after performance
started dropping off, and probably the bottom ten inches or so of the
tank was full of scale.

The tank is only 3 years old and we live in a soft water area so I'm pretty
sure that scale isn't a problem.

Tim

Andrew Gabriel wrote:
In article ,
"Tim+" writes:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with
a external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water
supplies which we suspect was due to a problem with our water mains
further down the street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has
cleared up but we continue to intermitently get dirt in our HW
supply which I've been putting down to a HW cyclinder full of silt.
If no water has been drawn for a while (like overnight) the HW is
visibly stained.

Today I thought I'd try and drain down the HW tank using the drain
cock to see what the water was like nearer the bottom of the tank
(expecting it to be really dirty). I filled half a bucket and
poured it into our sink and this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I
repressurised and and refilled the sink from the tap with this
result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg


What I want to know is, where the feck is all this crud hiding??
This always happens if I depressurise and repressurise the tank.
It's had a new pressure vessel about 3 weeks ago after the diaphragm
failed in the old one so I know it's not the pressure vessel that's
full of crud.

As I say, our cold supply seems okay but I'd really like to flush
all this crud out of our HW system but I'm mystified why water
drained from the bottom of the tank is so much cleaner than what's
coming out the top.

I'm guessing it is in the bottom, but it wasn't stirred up when
you tried draining from the bottom. Filling just the bottom and
emptying it a few times might do it. Does it have any kind of
access panel such as immersion heater tap that you could look in
when it's drained down (or drained below the access panel)?

No access panels. I think the main problem is that there is no separate
drain point and the lowest accessible point to drain it is the cold water
inlet which is about 18" up the side. I suspect the only way to do this
might be to syphon it down with a hosepipe inserted in the top but that's
going to involve disturbing quite a lot of soldered pipework. :-(

Tim

In article ,
"Tim+" writes:
Andrew Gabriel wrote:
I'm guessing it is in the bottom, but it wasn't stirred up when
you tried draining from the bottom. Filling just the bottom and
emptying it a few times might do it. Does it have any kind of
access panel such as immersion heater tap that you could look in
when it's drained down (or drained below the access panel)?

No access panels. I think the main problem is that there is no separate
drain point and the lowest accessible point to drain it is the cold water
inlet which is about 18" up the side. I suspect the only way to do this
might be to syphon it down with a hosepipe inserted in the top but that's
going to involve disturbing quite a lot of soldered pipework. :-(

I have visions of having to remove the cylinder, so you can
give it a good shake and sloshing out.
And then compression fittings, so it's easier to do next time;-)

Also a good excuse to buy one of those colonoscopy cameras from
Aldi/CPC/Maplin, if you haven't already...

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Tim+ wrote:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water supplies
which we suspect was due to a problem with our water mains further down
the street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has cleared
up but we continue to intermitently get dirt in our HW supply which I've
been putting down to a HW cyclinder full of silt. If no water has been
drawn for a while (like overnight) the HW is visibly stained.

Today I thought I'd try and drain down the HW tank using the drain cock
to see what the water was like nearer the bottom of the tank (expecting
it to be really dirty). I filled half a bucket and poured it into our
sink and this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I
repressurised and and refilled the sink from the tap with this result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg



What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had a
new pressure vessel about 3 weeks ago after the diaphragm failed in the
old one so I know it's not the pressure vessel that's full of crud.

As I say, our cold supply seems okay but I'd really like to flush all
this crud out of our HW system but I'm mystified why water drained from
the bottom of the tank is so much cleaner than what's coming out the top.

Tim

I think the answer is this.

(i) switch of all heat input
(ii) leave the hot taps all on full for as long as it takes. The
constant water flow should in the end stir up the silt enough to get it
all out.
(iii) any silt left is probably too heavy to ever come out again so who
cares?


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On 31/08/2012 15:49, Tim+ wrote:

No access panels. I think the main problem is that there is no separate
drain point and the lowest accessible point to drain it is the cold
water inlet which is about 18" up the side. I suspect the only way to
do this might be to syphon it down with a hosepipe inserted in the top
but that's going to involve disturbing quite a lot of soldered pipework.

There's no immersion heater?

On Fri, 31 Aug 2012 14:48:17 +0100, Tim+ wrote:

What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had a
new pressure vessel about 3 weeks ago after the diaphragm failed in the
old one so I know it's not the pressure vessel that's full of crud.

How about the pipe joining the pressure vessel to the rest of the system?

--
Cheers
Dave.

But hang on a moment...
If the source is now gone, assuming it was the cold supply, you should only
need to clear it out once. However if its still happening you might need to
worry about where it is in fact coming from or whatever you do will have to
be done over and over. I guess getting the pollution analysed would be too
costly?

Brian

--
--
From the sofa of Brian Gaff -

Blind user, so no pictures please!
"GB" wrote in message
...
On 31/08/2012 15:49, Tim+ wrote:

No access panels. I think the main problem is that there is no separate
drain point and the lowest accessible point to drain it is the cold
water inlet which is about 18" up the side. I suspect the only way to
do this might be to syphon it down with a hosepipe inserted in the top
but that's going to involve disturbing quite a lot of soldered pipework.

There's no immersion heater?

In message , Andrew Gabriel
writes
In article ,
"Tim+" writes:
Andrew Gabriel wrote:
I'm guessing it is in the bottom, but it wasn't stirred up when
you tried draining from the bottom. Filling just the bottom and
emptying it a few times might do it. Does it have any kind of
access panel such as immersion heater tap that you could look in
when it's drained down (or drained below the access panel)?

No access panels. I think the main problem is that there is no separate
drain point and the lowest accessible point to drain it is the cold water
inlet which is about 18" up the side. I suspect the only way to do this
might be to syphon it down with a hosepipe inserted in the top but that's
going to involve disturbing quite a lot of soldered pipework. :-(

I have visions of having to remove the cylinder, so you can
give it a good shake and sloshing out.
And then compression fittings, so it's easier to do next time;-)

Also a good excuse to buy one of those colonoscopy cameras from
Aldi/CPC/Maplin, if you haven't already...


I noticed that CPC were selling one with a USB I/f for £20-30 a couple
of weeks ago

(I bought a chainsaw - watch out world !)


--
geoff

In article ,
geoff writes:
In message , Andrew Gabriel
writes

Also a good excuse to buy one of those colonoscopy cameras from
Aldi/CPC/Maplin, if you haven't already...


I noticed that CPC were selling one with a USB I/f for £20-30 a couple
of weeks ago

I noticed Aldi have the standalone ones in (somewhere around £70, IIRC).

(I bought a chainsaw - watch out world !)

Aldi had those too, although the box was remarkably small so can't
have been big ones.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[Default] On Fri, 31 Aug 2012 14:48:17 +0100, a certain chimpanzee,
"Tim+" , randomly hit the
keyboard and wrote:

snip
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

That's a fuggin' bit pothole! I particularly like the tyre marks right
to the edge; is there a water board van in the bottom of that hole?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?

In message
,
Owain writes
On Sep 2, 5:14*pm, (Andrew Gabriel) wrote:
(I bought a chainsaw - watch out world !)
Aldi had those too, although the box was remarkably small so can't
have been big ones.

maybe they were flatpack?

They will be when I've finished

Yeah - dinky little electric chainsaw, but just what I need for my
rampant bay tree. I'm not felling douglas firs




--
geoff

On Friday, August 31, 2012 2:48:13 PM UTC+1, Tim+ wrote:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a

external 18L expansion vessel.



For some time now we've suffered from intermittant dirty water supplies

which we suspect was due to a problem with our water mains further down the

street (as manifest by the major blowout recently

http://i1052.photobucket.com/albums/...k/da49f87f.jpg )



Anyhow, our water supply (or at least our cold water supply) has cleared up

but we continue to intermitently get dirt in our HW supply which I've been

putting down to a HW cyclinder full of silt. If no water has been drawn for

a while (like overnight) the HW is visibly stained.



Today I thought I'd try and drain down the HW tank using the drain cock to

see what the water was like nearer the bottom of the tank (expecting it to

be really dirty). I filled half a bucket and poured it into our sink and

this is what it looked like

http://i1052.photobucket.com/albums/...EDFA1D3991.jpg

As you can see, only very lightly stained.



It seemed a bit pointless to carry on draining the tank so I repressurised

and and refilled the sink from the tap with this result.

http://i1052.photobucket.com/albums/...ED925ED3B6.jpg





What I want to know is, where the feck is all this crud hiding?? This

always happens if I depressurise and repressurise the tank. It's had a new

pressure vessel about 3 weeks ago after the diaphragm failed in the old one

so I know it's not the pressure vessel that's full of crud.



As I say, our cold supply seems okay but I'd really like to flush all this

crud out of our HW system but I'm mystified why water drained from the

bottom of the tank is so much cleaner than what's coming out the top.



Tim

The internal coil has probably failed; the crud is from the heating system.

The internal coil has probably failed; the crud is from the heating system.

I thought of that, but surely the OP would be forever topping up his
central heating system, and surely he'd have mentioned that? Assuming
it's an unvented system, ofc.

On Monday, September 3, 2012 10:57:57 AM UTC+1, GB wrote:
The internal coil has probably failed; the crud is from the heating system.



I thought of that, but surely the OP would be forever topping up his

central heating system, and surely he'd have mentioned that? Assuming

it's an unvented system, ofc.

The pressure in the CH & the unvented cylinder would equalise, so there may not be a loss of pressure in normal use.
He did say; "This always happens if I depressurise and repressurise the tank."
The CH would leak into the tank when he had drained it, so this scenario sounds plausible.

On 03/09/2012 11:27, Onetap wrote:
On Monday, September 3, 2012 10:57:57 AM UTC+1, GB wrote:
The internal coil has probably failed; the crud is from the heating system.



I thought of that, but surely the OP would be forever topping up his

central heating system, and surely he'd have mentioned that? Assuming

it's an unvented system, ofc.

The pressure in the CH & the unvented cylinder would equalise, so there may not be a loss of pressure in normal use.
He did say; "This always happens if I depressurise and repressurise the tank."
The CH would leak into the tank when he had drained it, so this scenario sounds plausible.


Ah, gotcha!

The OP can test this hypothesis by depressurising the central heating
circuit. If it fills itself up (from the HW tank), then you are right.

On Monday, September 3, 2012 12:12:26 PM UTC+1, GB wrote:
On 03/09/2012 11:27, Onetap wrote:

On Monday, September 3, 2012 10:57:57 AM UTC+1, GB wrote:

The internal coil has probably failed; the crud is from the heating system.







I thought of that, but surely the OP would be forever topping up his



central heating system, and surely he'd have mentioned that? Assuming



it's an unvented system, ofc.



The pressure in the CH & the unvented cylinder would equalise, so there may not be a loss of pressure in normal use.

He did say; "This always happens if I depressurise and repressurise the tank."

The CH would leak into the tank when he had drained it, so this scenario sounds plausible.





Ah, gotcha!



The OP can test this hypothesis by depressurising the central heating

circuit. If it fills itself up (from the HW tank), then you are right.

The CH would lose pressure after the tank was drained, but it could be a slow leak.
It should be covered by the maker's guarantee, if the OP has the receipts, so it would be a cheap fix, compared to most faults.

GB wrote:
On 03/09/2012 11:27, Onetap wrote:
On Monday, September 3, 2012 10:57:57 AM UTC+1, GB wrote:
The internal coil has probably failed; the crud is from the heating system.



I thought of that, but surely the OP would be forever topping up his

central heating system, and surely he'd have mentioned that? Assuming

it's an unvented system, ofc.

The pressure in the CH & the unvented cylinder would equalise, so there
may not be a loss of pressure in normal use.
He did say; "This always happens if I depressurise and repressurise the tank."
The CH would leak into the tank when he had drained it, so this scenario sounds plausible.


Ah, gotcha!

The OP can test this hypothesis by depressurising the central heating
circuit. If it fills itself up (from the HW tank), then you are right.

It doesn't. The HW tank is only 3 years old.

Tim

Onetap wrote:
On Friday, August 31, 2012 2:48:13 PM UTC+1, Tim+ wrote:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a

external 18L expansion vessel.



For some time now we've suffered from intermittant dirty water supplies

which we suspect was due to a problem with our water mains further down the

street (as manifest by the major blowout recently

http://i1052.photobucket.com/albums/...k/da49f87f.jpg )



Anyhow, our water supply (or at least our cold water supply) has cleared up

but we continue to intermitently get dirt in our HW supply which I've been

putting down to a HW cyclinder full of silt. If no water has been drawn for

a while (like overnight) the HW is visibly stained.



Today I thought I'd try and drain down the HW tank using the drain cock to

see what the water was like nearer the bottom of the tank (expecting it to

be really dirty). I filled half a bucket and poured it into our sink and

this is what it looked like

http://i1052.photobucket.com/albums/...EDFA1D3991.jpg


As you can see, only very lightly stained.



It seemed a bit pointless to carry on draining the tank so I repressurised

and and refilled the sink from the tap with this result.

http://i1052.photobucket.com/albums/...ED925ED3B6.jpg





What I want to know is, where the feck is all this crud hiding?? This

always happens if I depressurise and repressurise the tank. It's had a new

pressure vessel about 3 weeks ago after the diaphragm failed in the old one

so I know it's not the pressure vessel that's full of crud.



As I say, our cold supply seems okay but I'd really like to flush all this

crud out of our HW system but I'm mystified why water drained from the

bottom of the tank is so much cleaner than what's coming out the top.



Tim

The internal coil has probably failed; the crud is from the heating system.

Nope. It's a sealed CH system. No pressure loss

Tim

On Monday, September 3, 2012 8:44:24 PM UTC+1, Tim+ wrote:
Onetap wrote:

On Friday, August 31, 2012 2:48:13 PM UTC+1, Tim+ wrote:

We have a pressurised HW system (an Albion Ultrasteel cylinder) with a



external 18L expansion vessel.







For some time now we've suffered from intermittant dirty water supplies



which we suspect was due to a problem with our water mains further down the



street (as manifest by the major blowout recently



http://i1052.photobucket.com/albums/...k/da49f87f.jpg )







Anyhow, our water supply (or at least our cold water supply) has cleared up



but we continue to intermitently get dirt in our HW supply which I've been



putting down to a HW cyclinder full of silt. If no water has been drawn for



a while (like overnight) the HW is visibly stained.







Today I thought I'd try and drain down the HW tank using the drain cock to



see what the water was like nearer the bottom of the tank (expecting it to



be really dirty). I filled half a bucket and poured it into our sink and



this is what it looked like



http://i1052.photobucket.com/albums/...EDFA1D3991.jpg





As you can see, only very lightly stained.







It seemed a bit pointless to carry on draining the tank so I repressurised



and and refilled the sink from the tap with this result.



http://i1052.photobucket.com/albums/...ED925ED3B6.jpg











What I want to know is, where the feck is all this crud hiding?? This



always happens if I depressurise and repressurise the tank. It's had a new



pressure vessel about 3 weeks ago after the diaphragm failed in the old one



so I know it's not the pressure vessel that's full of crud.







As I say, our cold supply seems okay but I'd really like to flush all this



crud out of our HW system but I'm mystified why water drained from the



bottom of the tank is so much cleaner than what's coming out the top.







Tim



The internal coil has probably failed; the crud is from the heating system.



Nope. It's a sealed CH system. No pressure loss

mmm but the HW tank is mains pressure? & the CH is pressurised by the mains through the filling loop(when being re-pressuised)?

So spose the CH should be at a lower pressure than full-on mains? If you were to reduce slightly the pressure in the CH would it magically gain pressure (overnight say) from a possible leak in the HW tank coil between the mains pressure HW cylinder and CH system?

That wouldn't explain how the crud comes back out of the CH system into the HW tank to give mucky water - but would confirm no leaks in the HW tank coil?

Jim K

Well, I finally got around to disconnecting the pipework from the top of the
tank the other day and tried syphoning the water out with a hosepipe to see
if I could drain the mud from the bottom of the tank.

This didn't porduce the expected results so I assume that the hose was
coiling up in the tank. I found a bit of 15mm plastic pipe which made a
perfect "dip-tube" to reach to the bottom of the tank and started syphoning
again.

Again, there was hardly any discolouration.

Having drained of a good deal of water reassmbled everything and
repressurised the system, I just flushed all the hot taps for at least half
an hour each.

This produced some crud briefly but then the water ran clear.

Despite all this, I'm *still* getting some discolouration when first
openning a tap in the morning (shower and bathroom sink) . It's probably a
bit less marked than it was though. I think just *has* to be silt in the
pipework but it's proving very hard (and slow) to shift completely. :-(

I guess in time it will just clear up and I suspect it's the higher flow
rates induced by having a mains pressure tank now that is shifting all this
old crud but I'm amazed at how persistent the ruddy stuff is! The tank was
installed over a year ago and the problem has been going on all this time.

Tim



Tim+ wrote:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water
supplies which we suspect was due to a problem with our water mains
further down the street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has
cleared up but we continue to intermitently get dirt in our HW supply
which I've been putting down to a HW cyclinder full of silt. If no
water has been drawn for a while (like overnight) the HW is visibly
stained.
Today I thought I'd try and drain down the HW tank using the drain
cock to see what the water was like nearer the bottom of the tank
(expecting it to be really dirty). I filled half a bucket and poured
it into our sink and this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I
repressurised and and refilled the sink from the tap with this result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg


What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had
a new pressure vessel about 3 weeks ago after the diaphragm failed in
the old one so I know it's not the pressure vessel that's full of
crud.
As I say, our cold supply seems okay but I'd really like to flush all
this crud out of our HW system but I'm mystified why water drained
from the bottom of the tank is so much cleaner than what's coming out
the top.
Tim

Is it enough to be filtered in some way so you could just change the filter
every so often.

Brian

--
--
From the sofa of Brian Gaff -

Blind user, so no pictures please!
"Tim+" wrote in message
...
Well, I finally got around to disconnecting the pipework from the top of
the tank the other day and tried syphoning the water out with a hosepipe
to see if I could drain the mud from the bottom of the tank.

This didn't porduce the expected results so I assume that the hose was
coiling up in the tank. I found a bit of 15mm plastic pipe which made a
perfect "dip-tube" to reach to the bottom of the tank and started
syphoning again.

Again, there was hardly any discolouration.

Having drained of a good deal of water reassmbled everything and
repressurised the system, I just flushed all the hot taps for at least
half an hour each.

This produced some crud briefly but then the water ran clear.

Despite all this, I'm *still* getting some discolouration when first
openning a tap in the morning (shower and bathroom sink) . It's probably
a bit less marked than it was though. I think just *has* to be silt in
the pipework but it's proving very hard (and slow) to shift completely.
:-(

I guess in time it will just clear up and I suspect it's the higher flow
rates induced by having a mains pressure tank now that is shifting all
this old crud but I'm amazed at how persistent the ruddy stuff is! The
tank was installed over a year ago and the problem has been going on all
this time.

Tim



Tim+ wrote:
We have a pressurised HW system (an Albion Ultrasteel cylinder) with a
external 18L expansion vessel.

For some time now we've suffered from intermittant dirty water
supplies which we suspect was due to a problem with our water mains
further down the street (as manifest by the major blowout recently
http://i1052.photobucket.com/albums/...k/da49f87f.jpg )

Anyhow, our water supply (or at least our cold water supply) has
cleared up but we continue to intermitently get dirt in our HW supply
which I've been putting down to a HW cyclinder full of silt. If no
water has been drawn for a while (like overnight) the HW is visibly
stained.
Today I thought I'd try and drain down the HW tank using the drain
cock to see what the water was like nearer the bottom of the tank
(expecting it to be really dirty). I filled half a bucket and poured
it into our sink and this is what it looked like
http://i1052.photobucket.com/albums/...EDFA1D3991.jpg
As you can see, only very lightly stained.

It seemed a bit pointless to carry on draining the tank so I
repressurised and and refilled the sink from the tap with this result.
http://i1052.photobucket.com/albums/...ED925ED3B6.jpg


What I want to know is, where the feck is all this crud hiding?? This
always happens if I depressurise and repressurise the tank. It's had
a new pressure vessel about 3 weeks ago after the diaphragm failed in
the old one so I know it's not the pressure vessel that's full of
crud.
As I say, our cold supply seems okay but I'd really like to flush all
this crud out of our HW system but I'm mystified why water drained
from the bottom of the tank is so much cleaner than what's coming out
the top.
Tim

Tim+ wrote:
Well, I finally got around to disconnecting the pipework from the top
of the tank the other day and tried syphoning the water out with a
hosepipe to see if I could drain the mud from the bottom of the tank.

This didn't porduce the expected results so I assume that the hose was
coiling up in the tank. I found a bit of 15mm plastic pipe which
made a perfect "dip-tube" to reach to the bottom of the tank and
started syphoning again.

Again, there was hardly any discolouration.

Having drained of a good deal of water reassmbled everything and
repressurised the system, I just flushed all the hot taps for at
least half an hour each.

This produced some crud briefly but then the water ran clear.

Despite all this, I'm *still* getting some discolouration when first
openning a tap in the morning (shower and bathroom sink) . It's
probably a bit less marked than it was though. I think just *has* to
be silt in the pipework but it's proving very hard (and slow) to
shift completely. :-(
I guess in time it will just clear up and I suspect it's the higher
flow rates induced by having a mains pressure tank now that is
shifting all this old crud but I'm amazed at how persistent the ruddy
stuff is! The tank was installed over a year ago and the problem has
been going on all this time.

We've been scratching our heads over this for months and having ruled out
sludge in the tank and contaminated mains, I had decided that it had to be
rotting stainless pipework. (There's a lot of it about in houses in our
area).

Anyhow, I was resigning myself to lifting floors, changing pipes etc. when I
thought I'd have a last look at the pipework in the loft and it was only
then that I realised that we had a very large dead leg of SS pipework in the
loft (and leading back to the tank). This had been rendered mostly
redundant a few years back and other changes to the plumbing at another time
had rendered it totally redundant. Because the work was done at different
times by different people, I don't think anyone had realised that this leg
was now dead.

Anyhow, it's now removed and problem solved (I think). ;-)

Tim