In article ,
RJH wrote:
When my new boiler (Ideal Logic combi) was installed over 4 years ago,
it had 2 'power flushes' by the installer, and a magnet/filter fitted.
I've drained and refilled (with inhibitor) it 3 times since, and still
the water comes out black with a good few mm of sediment (I drain the
system from the lowest point into a trug). Nothing on the filter at all.
The black is almost oily - I've no idea what it is but must be coming
from the original radiators (only 3/14 left now).

The system is potentially prone to blockages (6 of the rads take 10mm
plastic pipe). All fine so far, but I'm wondering whether there's any
preventative action I can take before the inevitable.

It sounds like air is getting in somewhere. No oxygen, no corrosion.
You really don't want to change the water unless needed. As fresh water
contains air.

--
*What happens when none of your bees wax? *

Dave Plowman London SW
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