Hot Water Cylinder - Advice Needed Please

prend

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We have a copper hot water cylinder which is 11 years old. For the past while there have been 'bits' coming out in the water - mostly noticable when you fill a bath. I got a friend to empty and flush out the cylinder (without disconnecting it) and it did help but now its back .. it has been flushed a few times now and I'm getting really fed up with it. The 'bits' are black pieces in the water - some very tiny but now this evening bigger bits.
So now I'm thinking it must be the cylinder disentigrating ???
And I am thinking maybe I'd be best replacing it to finally solve this ... I started reading a bit on here and see Stainless Steel cylinders recommended.

So I have some questions - should I replace the cylinder? Or do I need to?
If so then should I go for a stainless steel one?
I looked for prices but am not sure which stainless steel one I'd need ... I'm not sure on size - it was a "standard" size back then .. how many coil cylinder do I need .. I think 2 as I have a "Willis" heater installed which quickly heats a smaller amount of hot water so I think it must have 2 coils??? .. And can someone explain heat recovery also or is that just for solar?

Sorry for so many Qs - just want to see if its feasible for us to change .. or if its needed

Thanks in advance
 
Suggest you check your water storage tank in the attic as this is where your water supply is fed to the copper cylinder - maybe the water in the storage tank is contaminated / dirty especially if its a metal one. If this is the case you may consider replacing it with a plastic one.
 
Suggest you check your water storage tank in the attic as this is where your water supply is fed to the copper cylinder - maybe the water in the storage tank is contaminated / dirty especially if its a metal one. If this is the case you may consider replacing it with a plastic one.

Hi,
The storage tank in the attic is plastic and we cleaned it out the first time ... yes there was dirt in it .. the supply wasn't the greatest quality but the supply has been upgraded and we have a filter on it up there so the tank is clean now. We flushed the cylinder after this was done.
I got him to check the tank a few weeks ago to make sure it was still clean and he emptied it out again as a precaution but it was clean so its definately the cylinder thats the problem ... could there still be bits in it months and months later?? I'm thinking it might be coming off the inside of the tank?? .. Is it a huge job to take off the entire tank and wash it out properly? ... Its the only way to make sure its all out as the discharge feed is above the very bottom of the tank so it never drains 100%
 
The black bits you mention - are they metal bits ? or just dirt that may have been in the storage tank. Its unlikely that copper would corrode on the inside but think it would not be necessary to install a stainless steel one. If you are handy with tools you might consider screwing off the immersion heater and shining a light into the cylinder - then you might be able to see the extent of the problem.
 
I'm not really sure what the bits are tbh .. most of them are small specks .. but they are black rather than rust coloured so maybe its still dirt. .. Would it be unusual for a copper tank to do this?
I am not handy at all and would be afraid to mess with the tank but think maybe the best step is take it off completely and wash it out that way .. I just don't want to be doing that and paying someone to do it and then discovering a few months later that the problem is back and we should replace the tank if you know what I mean
 
We had this problem good while back, have a post up here about it, bath full of limescale, some rads only getting lukewarm.

unfort we went down the road you want to avoid, paying a plumber a couple of times, he replaced our circulating pump, cut out a huge chuck of copper pipe, fitted a handle type end to a pipe and then came back and took every rad off the walls and flushed them out with a hose. he also added so sort stuff to the system with added benefit of stopping any leaks (which did work cos the playroom rad also leaked a little bit on to the tiles which i had to wipe every few days!).

we had lost faith in him at the end but thankfully he managed to solve the problems.
 
Ah sugar!! ... I just checked some of the rads and they seem to be heating at the top but not the bottom .. was this what yours was doing? .. Could be full of gunk here.
All the things you mention he replaced - was that before or after he figured out the problem? ...
I checked the bath again and some of the 'bits' are hard so could be metal .. most of them are pinhead sized or a bit larger but the last few times there have been some bigger bits in it ... I dread to think whats being held in the taps and showers ...
Whatever we do now I want it sorted once and for all .. its driving me batty!!
 
With a powerflush, no rads have to be removed. If there is scale within the heating system, I use Fernox DS40 about a week before the flush, as this will break down any scale. When it is flushed, a neutraliser is used to neutralise the chemical.
If no scale but system is sludged, then I use Fernox F5 Heavy Duty Powerflushing Chemical.
 
Thanks for both replies - I think it will need to be flushed out one way or another .. as far as I can remember the system was drained and flushed (??) a couple of years ago when the attic tank was cleaned out.

Shane - can I ask some questions please ..
* How is the powerflush done?
* How do you know if the system is sludge or if its scale thats the problem? .. Is there a way of figuring it out?
* Also, where can I get hold of the Fernox do you know and so you know what the neutraliser is called?

Its a friend who is kind of a jack of all trades that cleaned out the tank for us before and if its faitly straightforward he might be able to do this for us or do you think we'd need a plumber?

Also, is there a way of figuring out if the problem is with the cylinder also .. or the coil?

Sorry for so many questions .. trying to get my head around it
 
* A special powerflushing machine is required to carry out the flush. It cannot be done otherwise. A drain & fill will not remove sludge sitting in the bottom of the radiators.
See this link: http://www.slideshare.net/FernoxMarketing/powerflushing-leaflet-uk
* It can be determined by a number of factors. Do you need to bleed air from your system on a regular basis? When you bleed rads, does it come out clear or black? By removing the head of the circulating pump, sludge build up can be seen there and it's colour (red or black) will determine how recent the issue is.
However, you can take a sample of water from your system and a test can be carried out by the operative also.
* Most decent plumbing merchants stock it or can order it in, but without the proper equipment, it is really not worth it and a waste of money.
* Leave Jack where he is...
* Yes, by removing the immersion, with a torch, the inside of the cylinder, including the coil can be inspected. How long does the boiler take to heat the hot water? I replaced a cylinder once that took 3 hours to get it you luke warm. It took 2 of us to lift the 30" x 18" out, it was full to the brim with limescale. Is your area or well high in lime?
 
Sludge and dirt in the radiators would not cause contamination in the hot water cylinder unless the heating coil was burst. This would have to be checked by draining the central heating system and opening the lower coil connection at the cylinder. If there is a continuous leaking from the coil it is burst.
 
Shane - I am assuming by looking at the link you gave that it is a specailist you need to do this flushing rather than just a regular plumber ... can you tell me where or how I might find a list of people that do this?
The rads don't seem to need bleeding ..they are hot at the top - the bottom is warm but not as hot as the top. I do remember bleeding them a long time ago and there was some dirty water coming out .. I wouldn't say totally black but definately dirty, not clear.
Am I right assuming if any sludge in the pump head is red then its recent sludge?
The boiler doesn't take that long to heat .. maybe half an hour for a decent length shower or a bath.

bstop, can the coil be taken out of the cylinder? Or am I picking you up wrong?
Before I get anyone in to sort this I want to have straight in my head exactly what needs doing and how it should be done .. want it sorted once and for all one way or the other.
 
It is specialist. The equipment is expensive and the accessories very expensive, so not many around that do it. If it is required it is very worth while.
Yes you are correct, if red it is recent, black a more prolonged and slower issue.
Your system may not be sludged, it could be an under-sized circulating pump or a balancing issue or sludge. If the system is open vented, check your attic to see if you have a small tank, wipe the inside bottom of the tank, under the water, and see if your finger comes out black. This is another sign.
If it is a scale issue within the heating system, then this is due to a leak and fresh water being continuously being introduced to the system, thus bringing in scale. The red inside of the pump a good indicator.
Regarding the coil, you cannot take it out but the cylinder could be and wash out of any debris and refitted if nothing wrong with it. If scaled up, it is usually a new cylinder, but it really depends on the level of the scale.
 
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