Lobster wrote:
Andy Hall wrote:
On 2008-05-27 20:46:22 +0100, Mark said:

I have just removed a radiator & noted that a small amount of black
water came out (which later settled out into brown sand-like grains).

The majority of the system is fairly new (all radiators and boiler)
but there is some old pipework. The boiler is a W-B combi (i.e.
sealed). There are no leaks in the system.

I see that there are a huge number of chemical cleaner products and
inhibitors. How can I tell which would be most suitable for my
system?

The first thing is that you need to thorughly flush out the sludge and
solids.

There are two reasonable ways to do that:

- Drain system, remove radiators, take them outside and flush them
with a mains hose or pressure washer. Flush water out at each
radiator position.

- Power flush the system. This can be done by paying someone N x
hundred ££s or by renting the equipment and DIYing it.

Not disagreeing that either of the above are the ideal solutions, but
both are reasonably drastic in terms of hassle factor and/or cost. Given
that the majority of the OP's system is pretty new I'd go for something
like Sentinel X400 cleanser, and repeated fill/flush/drain cycles
http://www.screwfix.com/prods/89458/Plumbing/Central-Heating-Treatment/Sentinel-X400-Central-Heating-Sludge-Remover


followed by say Sentinel X100 inhibitor:
http://www.screwfix.com/prods/79683/Plumbing/Central-Heating-Treatment/Sentinel-X100-Central-Heating-Scale-Inhibitor-1Ltr


If nothing else, I'd say get something into the system asap as Lobster
describes. Any brand would be better than none. You might wish or need
to leave it a few weeks before you can tackle the full clean. (The
system cleaners need to be left in for a while to work properly. And it
might just not be convenient to do more at the moment.)

You might also care to consider why it was left without? I'd be checking
anything the installer left - bills, etc. - which might claim to have
done a power flush and filled with inhibitor. And any warranty provided.

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org