Help Needed

[Frustrated]

hi all and I hope someone will be able to help.
My partner and I recently (seven months ago) paid to have a back boiler hot water and heating system installed in our home. The installation went reasonably okay. However the Warmflow hot water cylinder leaked immediately and only after repeatedly asking the plumbing, who was still on site, to deal with it, did a representative of Warmflow inspect the cylinder. he confirmed the tank was leaking. A new cylinder was installed and this lasted two weeks before the same leak occured; a third cylinder was installed and this has lasted the longest, but this morning the same leak (at the top) has started again. In the interim period two elements have developed a short and we're now on number 2. However that was only fitted yesterday and we're not holding out any hope of it surviving the 24 hours the previous one did before a fault occurs.

Has anyone come across similar problems with unvented hot water cylinders and elements or are we just the most unlucky people around?

[AWheating]

hi mate and welcome to the forum. Is this an solid fuel back boiler? if not i would request the post be moved to another folder as this folder is for solid fuel, oil etc.... and dose not get as many readers as the standard plumbing and central heating folders.

[jtsplumbing]

What is your back boiler running off ? gas / oil / or somthing else ! and what make is it ?

[Frustrated]

Hi sorry for not getting back on sooner. however the system we have is a log burner back boiler. the cylinders we have are Warmflow stainless steel cylinder. As we're on well water with no pressure the plumber installed a pressurising pump which sorts out the water flow problem as we don't have space in the loft to house the water tanks. Latest update is he is suggesting we swap the warmflow tank for a copper tank. However am I wrong in thinking you can't use a copper tank in a pressurised system? all suggestions greatly appreciated.

[Gary71]

You need to start with your well water, get it tested, once you have the results talk to the manufactures and a filter installer to see if you can have a filter fitted to treat the water and take the aggressiveness out.

Glass lined unvented cylinders can deal with well water issues better than SS but it is dependant on the water.

[Frustrated]

Hi we're just waiting for the water tests to come back but already know we have a ph of 7 though slightly hard water. Have spoken to several water engineers re filter system and posed the question to them about the water and the tanks and all have stated nothing in the water would cause any corrosion in stainless steel that quickly (immediate leak on first tank; two weeks for second tank and four weeks for third tank) - all on the top pipe. Plumber did a pressure test on the second tank and it showed there was a hole at this junction.

[Gary71]

The starting point has to be your water if only to rule it out, it is unusual for well water to have a impact so quickly but because your elements are going as well it is pointing to a water issue, if you can get the water delt with then it's easier to identify a bad workmenship problem.

[SimonG]

I would like to know how your unregulated heat source is tied into your unvented cylinder?

[Frustrated]

We've had the water tests back and it shows a ph of 7.45 and the science officer has stated there is nothing in the water which could damage the stainless steel tank. Manganese being the only thing which was well high, but fixable with a filter which we will invest in and have already been speaking with a company re this.
Simon G don't understand what you're asking. the log burner has pipes going directly to the cylinder. when the water gets up to temperature it switches over to feed the central heating. the tank is pressurised to about 3 bar and we have an inline pump before the tank which is fed from two cold water tanks which in turn is fed by a pump in the well.

[SimonG]

We've had the water tests back and it shows a ph of 7.45 and the science officer has stated there is nothing in the water which could damage the stainless steel tank. Manganese being the only thing which was well high, but fixable with a filter which we will invest in and have already been speaking with a company re this.
Simon G don't understand what you're asking. the log burner has pipes going directly to the cylinder. when the water gets up to temperature it switches over to feed the central heating. the tank is pressurised to about 3 bar and we have an inline pump before the tank which is fed from two cold water tanks which in turn is fed by a pump in the well.

Trying to ascertain your method of connecting an unregulated heat source to an unvented cylinder. Are you sure it's an unvented cylinder, does it presure and pressure temperature relief valves? Are you in England? Just wanting to know how safe the installation is. Because from what you've said it isn't.

[Frustrated]

there are pressure relief valves sorry didn't mention that.

[peteheat]

Your system must be vented for solid fuel, sorry pressure relief valves are not sufficient especially on the system you describe, at best you are depending on a pumped water supply to top the system up should it need to blow off.

You can get un-vented copper cylinders they are very expensive, you might want to consider an annode (magnesium or titanium) to protect the cylinder.

[Frustrated]

Hi pete and thanks for that. There is a blow off valve and there is also an expansion (is that what you call it) pipe leading to the outside. The lastest situation is Warmflow have opened up the previous two tanks, 'done a diagnostic' they say and it's the welds. They say the welds have been eaten away by our water (even though we have experts and documentation to prove otherwise). However they say 'we're going to build a special tank for you' and ship it right away. In other words, the way I read it, they've admitted the tanks were faulty and low. Otherwise why would they supply yet another tank, and if we are to believe them, they've specially constructed this one, under warranty if our water was to blame?
I take it no one has had any experience of this company - bad/good?

[Gary71]

Well water and SS do not get on and is a common enough problem depending on the water, I have never seen a expert or science officer onsite to help me when I have to figure out why a cylinder is leaking.

Usually for me the problems are sorted with a filter. The issues you are having are rarely caused by mains water which make up the main use for these cylinders. As it's such a small problem to the manufacture it's not dealt with, if it were costing them money they would deal with it. I think it's a good thing they want to help you as a lot of manufactures would only be able to give you your money back.

[Gary71]

Also I do get nervious when a unvented is fed by a back boiler, I like it when a appliance has a overheat fitted.