I've just been in the loft, and thought that while I was there I'd look
into the cold water tank (incredibly corroded parts, the tank itself
being PVC, but it all works) and the CH feed/overflow tank.

The CH tank has a skin on it that must be at an inch deep - browny,
almost solid gunge on top, pitch black underneath where it's in contact
with the surface of the water. Looks absolutely ghastly.

I am intending to get the CH boiler serviced this Spring/Summer. (I
rarely get it serviced, on the old adage "if it ain't broke don't fix
it". However it's almost 6 years since it was last looked at, so I think
it's time.)

So: when getting the boiler serviced, should I get the tank looked at as
well?


Note 1: I took care not to stir it up after I'd discovered the gunge.
However I'd guess that part of the reason this skin has formed is that
the system doesn't access the tank much, if at all.

Note 2: I have both cold water and CH tanks covered with thick insulated
boards, to prevent freezing -- was that a bad idea?


Note 3: this is a patchwork system (like most, I'd guess): rads and
pipework (microbore) fitted at least 35 years ago; new boiler and
controls and minor mods in 2008; and the boiler, which is a Gloworm
Flexicom HX, had a new heat exchanger fitted in 2015. Nothing since then.

Thanks in anticipation, for any views!

John

On 04/03/2021 16:12, Another John wrote:
I've just been in the loft, and thought that while I was there I'd look
into the cold water tank (incredibly corroded parts, the tank itself
being PVC, but it all works) and the CH feed/overflow tank.

The CH tank has a skin on it that must be at an inch deep - browny,
almost solid gunge on top, pitch black underneath where it's in contact
with the surface of the water. Looks absolutely ghastly.

I am intending to get the CH boiler serviced this Spring/Summer. (I
rarely get it serviced, on the old adage "if it ain't broke don't fix
it". However it's almost 6 years since it was last looked at, so I think
it's time.)

So: when getting the boiler serviced, should I get the tank looked at as
well?


Note 1: I took care not to stir it up after I'd discovered the gunge.
However I'd guess that part of the reason this skin has formed is that
the system doesn't access the tank much, if at all.

Note 2: I have both cold water and CH tanks covered with thick insulated
boards, to prevent freezing -- was that a bad idea?


Note 3: this is a patchwork system (like most, I'd guess): rads and
pipework (microbore) fitted at least 35 years ago; new boiler and
controls and minor mods in 2008; and the boiler, which is a Gloworm
Flexicom HX, had a new heat exchanger fitted in 2015. Nothing since then.

Thanks in anticipation, for any views!

I don't know if it was related, but my system had no inhibitor for years
(I'd refilled after some changes and never got around to it). When I
added some, a horrible scum soon formed in the tank!

I guess any gunge in the system has to end up somewhere!
Can it not simply be scooped out and the water in the tank filtered somehow
so it can start from scratch, Maybe done when the heating is off.

Obviously!
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.!
"Steve Walker" wrote in message
...
On 04/03/2021 16:12, Another John wrote:
I've just been in the loft, and thought that while I was there I'd look
into the cold water tank (incredibly corroded parts, the tank itself
being PVC, but it all works) and the CH feed/overflow tank.

The CH tank has a skin on it that must be at an inch deep - browny,
almost solid gunge on top, pitch black underneath where it's in contact
with the surface of the water. Looks absolutely ghastly.

I am intending to get the CH boiler serviced this Spring/Summer. (I
rarely get it serviced, on the old adage "if it ain't broke don't fix
it". However it's almost 6 years since it was last looked at, so I think
it's time.)

So: when getting the boiler serviced, should I get the tank looked at as
well?


Note 1: I took care not to stir it up after I'd discovered the gunge.
However I'd guess that part of the reason this skin has formed is that
the system doesn't access the tank much, if at all.

Note 2: I have both cold water and CH tanks covered with thick insulated
boards, to prevent freezing -- was that a bad idea?


Note 3: this is a patchwork system (like most, I'd guess): rads and
pipework (microbore) fitted at least 35 years ago; new boiler and
controls and minor mods in 2008; and the boiler, which is a Gloworm
Flexicom HX, had a new heat exchanger fitted in 2015. Nothing since then.

Thanks in anticipation, for any views!

I don't know if it was related, but my system had no inhibitor for years
(I'd refilled after some changes and never got around to it). When I added
some, a horrible scum soon formed in the tank!

On 04/03/2021 16:12, Another John wrote:
I've just been in the loft, and thought that while I was there I'd look
into the cold water tank (incredibly corroded parts, the tank itself
being PVC, but it all works) and the CH feed/overflow tank.

Soft water region? Mine the limescale builds up on the regular splashes.

The CH tank has a skin on it that must be at an inch deep - browny,
almost solid gunge on top, pitch black underneath where it's in contact
with the surface of the water. Looks absolutely ghastly.

Your problem will be if you ever need to drain down the CH system in a
hurry. Thick brown gunge and microbore piping do not get on at all well.

Is it organic looking gunge or precipitated copper/iron hydroxide rust?

I'm slightly surprised that it floats.

I am intending to get the CH boiler serviced this Spring/Summer. (I
rarely get it serviced, on the old adage "if it ain't broke don't fix
it". However it's almost 6 years since it was last looked at, so I think
it's time.)

So: when getting the boiler serviced, should I get the tank looked at as
well?


Note 1: I took care not to stir it up after I'd discovered the gunge.
However I'd guess that part of the reason this skin has formed is that
the system doesn't access the tank much, if at all.

Note 2: I have both cold water and CH tanks covered with thick insulated
boards, to prevent freezing -- was that a bad idea?

That it is covered means it isn't due to a dead bird or bat rotting away
in the tank and providing nutrients for the brown gunge.

Note 3: this is a patchwork system (like most, I'd guess): rads and
pipework (microbore) fitted at least 35 years ago; new boiler and
controls and minor mods in 2008; and the boiler, which is a Gloworm
Flexicom HX, had a new heat exchanger fitted in 2015. Nothing since then.

Thanks in anticipation, for any views!

Was there any inhibitor in the system?

--
Regards,
Martin Brown

On 04/03/2021 16:42, Martin Brown wrote:

I'm slightly surprised that it floats.

I've seen the same with a floating light brown layer in an insulated
plastic tank with lid and with inhibitor always used in the system. I
found the gunge to be the consistency similar to that of a weak
wall-paper paste and around 5mm deep. I turned off the service valve to
the tank and used a wet and dry vacuum cleaner to empty the tank - a
PITA as the tank held more water than the vacuum cleaner could suck up
in one go, and it needs to be emptied. The tank may have experienced
some short periods of pumping over during its life in the loft so at
some time it may have contained hot water.

I agree that its not something I would want going into a micro-bore
system and I'm not sure that anyone servicing the boiler would consider
emptying the loft tank in a way that the crude doesn't enter the system
to be part of the boiler service.


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

OP here -- thanks very much for all replies so far: useful I especially
like Alan's suggestion of using a wet/dry cleaner for emptying the tank.

In reply to Martin:

In article ,
Martin Brown wrote:

Is it organic looking gunge or precipitated copper/iron hydroxide rust?

I'm slightly surprised that it floats.

Ooh - that's a bit technical for me Martin! You won't find a
less-science-educated duffer than myself!

But I will attempt a picture tomorrow ... before I get the vac. out!

John

BTW - what do I use for publishing pics these days? I always used to
use Tinypic, but it's looked rather grotty to me the last couple of
times I used it. [Update: In fact I've just seen that Tinypic is
deceased.]

"Another John" wrote in message
...

snip

BTW - what do I use for publishing pics these days? I always used to
use Tinypic, but it's looked rather grotty to me the last couple of
times I used it. [Update: In fact I've just seen that Tinypic is
deceased.]

Postimage
- https://postimages.org/login

--
Regards
wasbit

Another John wrote:
I've just been in the loft, and thought that while I was there I'd look
into the cold water tank (incredibly corroded parts, the tank itself
being PVC, but it all works) and the CH feed/overflow tank.

The CH tank has a skin on it that must be at an inch deep - browny,
almost solid gunge on top, pitch black underneath where it's in contact
with the surface of the water. Looks absolutely ghastly.

I am intending to get the CH boiler serviced this Spring/Summer. (I
rarely get it serviced, on the old adage "if it ain't broke don't fix
it". However it's almost 6 years since it was last looked at, so I think
it's time.)

So: when getting the boiler serviced, should I get the tank looked at as
well?


Note 1: I took care not to stir it up after I'd discovered the gunge.
However I'd guess that part of the reason this skin has formed is that
the system doesn't access the tank much, if at all.

Note 2: I have both cold water and CH tanks covered with thick insulated
boards, to prevent freezing -- was that a bad idea?


Note 3: this is a patchwork system (like most, I'd guess): rads and
pipework (microbore) fitted at least 35 years ago; new boiler and
controls and minor mods in 2008; and the boiler, which is a Gloworm
Flexicom HX, had a new heat exchanger fitted in 2015. Nothing since then.

Thanks in anticipation, for any views!

John


Ive seen one with some nasty stuff which looks like brown pond weed I
think is from being repeatedly topped up with inhibitor. I suggest you
clean the tank drain the system fill with water and cleaner run for a week
or two then flush. Then refill will fresh water and inhibitor.

The system should be flushed every few years ideally with a hose.

In article ,
Radio Man wrote:

Ive seen one with some nasty stuff which looks like brown pond weed I
think is from being repeatedly topped up with inhibitor. I suggest you
clean the tank drain the system fill with water and cleaner run for a week
or two then flush. Then refill will fresh water and inhibitor.

The system should be flushed every few years ideally with a hose.

You could be right Radio Man -- I am guessing that the system has never
been flushed since 2008, when the new boiler was installed (along with
more pipework, rads, and this expansion tank), but that inhibitor has
been added a couple of times by visiting plumbers, or even by myself
(don't ask me what hey, or I, might have been doing: 'the past is a
foreign country' to me now).

To add emphasis to it, I'm about to add another part to this thread,
because I think I have fixed the problem. !!!

John

OP he I THINK I'VE FIXED IT.

I went up the loft this morning to take pictures (see below). I took
with me an egg, and even a can of beans: I was sure that the gunge-mat
that had formed would support at least the egg! But in fact it felt like
it would slip through, so I didn't risk it.

Then I thought: well, since I'm here, why not siphon it all out? In
short, that's what I did:

1. Switched off the system.
2. Tied up the ballcock to prevent filling while working.
3. Stuck a cork in the outlet to the CH system (very gently, so as not
to disturb the sediments).
4. Ran a hose to the bath, sucked at it, hastily stopped sucking when
the resistance went -- and off we went.

The gunge was solid, but very squidgy, and so went down the hose no
bother (it did block the bath-plug, when running away, but the
siphon-suction was strong enough to prevent blockage in the hose).

I took a soft brush (from a brushpan set - that size) to clean the ****
off the tanks and ballcock, and ran the sucking hose around to get it
all away. I refilled and siphoned the tank twice, and then finally
filled it a third time. I'll look at it in a week's time.

While I was there I looked again at the cold water tank: the water's
(reasonably) clean, but the ballcock mechanics are very cruddy -- any
suggestion for that? Replace entirely?

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?


I took photos, and I used the recommendation from Jimmy Stewart (in
Adam's thread), for imgbb ("simple and free"). It seems to do what it
says on the tin, and it's a _very_ good interface (what is their pound
of flesh I wonder?)

I made an album of 6 photos (all of which expire in two weeks time). It
is "Private but readable by anyone with the link" -- which is this:

https://ibb.co/album/6rnZ46

You can change the view to A-Z, which is the best as they are numbered:

1. What I saw yesterday, and sent me running straight to D-I-Y!
2. Close-up of the "gunge-mat".
3. I lifted a piece of the mat out and put it on the side.
4. Close-up of that piece.
(You don't need a pic of a clean expansion tank!)
5. and 6. are pics of the cold water tank, specifically the very cruddy
ballcock-works.


Hope this has been of interest to a few (what with learning about imgbb
as well as typing this, I think it's taken longer than this morning's
operation! :-D

Thanks _very_ much to those who offered opinions and advice!

John (Another)

On 06/03/2021 12:51, Another John wrote:
While I was there I looked again at the cold water tank: the water's
(reasonably) clean, but the ballcock mechanics are very cruddy -- any
suggestion for that? Replace entirely?

Are you in a hard water area ?. I get cruddy deposits on my cold
tank ballcock like yours. I'm not sure if there is a solution, maybe
remove, clean off deposits with vinegar or other mildly acidic substance
and then smear with grease before replacing.

Brass ballcocks are not that expensive though. I keep a couple in
'stock' as spares.

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?

Tanks should be covered and insulated in such a way that no light can
penetrate the tank because this encourages algae, and there are
micro orghanisms that can grown in a hostile environment like your
C/H header tank.

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?

Last month, on the coldest weekend of the year, my CH entirely ceased to function.
Like the OP describes, it's a piecemeal system, some parts being close to 50 years old. When we moved here in 2017, we had the system cleaned out and a new boiler installed. Everything was fine until early February when a series of faults coincided. A very expensive month and some complex work by the CH engineer has resulted in a brilliantly improved system but my problems were partly due to a corroded loft tank containing the sort of gunge described above.
This has now been replaced by a new tank, made of non-corrosive material and supplied with a cover as recommended by my CH guru. The idea is to prevent detritus from outside getting into the tank - dust and grit, pigeon droppings, dead rats, etc.
So I think the answer is yes, covering your tank can only be a help.

On 06-03-2021 12:51, Another John wrote:
OP he I THINK I'VE FIXED IT.

I went up the loft this morning to take pictures (see below). I took
with me an egg, and even a can of beans: I was sure that the gunge-mat
that had formed would support at least the egg! But in fact it felt like
it would slip through, so I didn't risk it.

Then I thought: well, since I'm here, why not siphon it all out? In
short, that's what I did:

1. Switched off the system.
2. Tied up the ballcock to prevent filling while working.
3. Stuck a cork in the outlet to the CH system (very gently, so as not
to disturb the sediments).
4. Ran a hose to the bath, sucked at it, hastily stopped sucking when
the resistance went -- and off we went.

The gunge was solid, but very squidgy, and so went down the hose no
bother (it did block the bath-plug, when running away, but the
siphon-suction was strong enough to prevent blockage in the hose).

I took a soft brush (from a brushpan set - that size) to clean the ****
off the tanks and ballcock, and ran the sucking hose around to get it
all away. I refilled and siphoned the tank twice, and then finally
filled it a third time. I'll look at it in a week's time.

While I was there I looked again at the cold water tank: the water's
(reasonably) clean, but the ballcock mechanics are very cruddy -- any
suggestion for that? Replace entirely?

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?


I took photos, and I used the recommendation from Jimmy Stewart (in
Adam's thread), for imgbb ("simple and free"). It seems to do what it
says on the tin, and it's a _very_ good interface (what is their pound
of flesh I wonder?)

I made an album of 6 photos (all of which expire in two weeks time). It
is "Private but readable by anyone with the link" -- which is this:

https://ibb.co/album/6rnZ46

You can change the view to A-Z, which is the best as they are numbered:

1. What I saw yesterday, and sent me running straight to D-I-Y!
2. Close-up of the "gunge-mat".
3. I lifted a piece of the mat out and put it on the side.
4. Close-up of that piece.
(You don't need a pic of a clean expansion tank!)
5. and 6. are pics of the cold water tank, specifically the very cruddy
ballcock-works.


Hope this has been of interest to a few (what with learning about imgbb
as well as typing this, I think it's taken longer than this morning's
operation! :-D

Thanks _very_ much to those who offered opinions and advice!

John (Another)


You're welcome. I hope it stays clear.

On 06/03/2021 12:51, Another John wrote:

While I was there I looked again at the cold water tank: the water's
(reasonably) clean, but the ballcock mechanics are very cruddy -- any
suggestion for that? Replace entirely?

Leave it alone until it fails. Water splashes dry and deposit tiny
amounts of calcium carbonate. It looks bad but does no real harm.

Even on the cold tank it is surprising how a few splashes can contrive
to jump out when the lid is not on the top. And more importantly it
prevents ingress of dead flies, bats, pigeons and any other wildlife.

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?

Something waterproof is much better. Otherwise you will have a soggy
mouldering wet thing up there causing trouble. I ran my hot header tank
without its cover on for a couple of hours whilst testing the immersion
heater. It would have totally messed up the loft humidity like that.

--
Regards,
Martin Brown

In article ,
Martin Brown wrote:

On 06/03/2021 12:51, Another John wrote:

While I was there I looked again at the cold water tank: the water's
(reasonably) clean, but the ballcock mechanics are very cruddy -- any
suggestion for that? Replace entirely?

Leave it alone until it fails. Water splashes dry and deposit tiny
amounts of calcium carbonate. It looks bad but does no real harm.

Even on the cold tank it is surprising how a few splashes can contrive
to jump out when the lid is not on the top. And more importantly it
prevents ingress of dead flies, bats, pigeons and any other wildlife.

Final request for advice (I jolly well hope): I had covered both these
tanks with a solid cover, and insulation. Was this a mistake? Would an
old blanket (or anything else that might protect from severe frost etc,
but allow breathing) have been better?

Something waterproof is much better. Otherwise you will have a soggy
mouldering wet thing up there causing trouble. I ran my hot header tank
without its cover on for a couple of hours whilst testing the immersion
heater. It would have totally messed up the loft humidity like that.

Thanks a lot Martin -- very helpful.

John