Dirty hot water mystery

sounds plausible.

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

Tim

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

Tim

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 we= re to reduce slightly the pressure in the CH would it magically gain pressu= re (overnight say) from a possible leak in the HW tank coil between the mai= ns 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 co= il?

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:

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

Brian

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