Flushing rads & pipes

snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:

Probably better to use mains water than a Circulation Pump

snipped-for-privacy@gmail.com submitted this idea :

You can buy flushing additives, which you leave in for a while. You could also take radiators out completely and flush them through outside with a hose.

When it is all done, make sure you add inhibitor and it is worth fitting a magnetic filter - they have strong magnet, which collects rust and steel particalparticle, you then pull the magnet out and simply let it flush them into a container.

I suppose a series of strong magnets clamped around a wide pipe, which could be removed, to then allow the particals to be flushed, would work, but cost wouldn't be much cheaper than a ready made filter.

I have zero experience of such issues, my system has had inhibitor in since it was installed in the 1980's, but I had a magentic filter added with a recent new boiler as an additional safe guard.

Richard

snip beginner's advice

That might work, though won't pick out biofouling, which is an unknown percentage of the problem. Wouldn't cost anything.

I was wondering about a round container with connectors terminating in elbows inside to get some cyclonic action, or perhaps something as basic as a rectangular box would see rust & sludge sink. I could add a magnet in a bag near the outlet.

NT

The pump approach is ok if you want to circulate some kind of system cleaner. However mains water and a drain is the easy way to get the bulk of the crap out of it.

I got good result doing:

The ground floor has 2 drain points, neither of which work due to cloggage. Adding more is not likely to work as there is not much ground floor action. There's also no way to isolate the boiler other than by doing some plumbing (gasp), access to which is problematic. The system has cleaner in & a mag filter fitted. So I was thinking initially of pumping between the 2 drain points. Rads have been removed & flushed before, it seems the junk lies in the pipework, which is not ideally laid out.

Maybe I'll just go with a box and a magnet & scourer as a filter - anything finer can be caught by the existing system filter.

NT

Sticking full mains flow into a a rad tail, and then venting it at various points (other tail, drain point, drain point 2 etc) will let you clear the system in sections. Isolating all rads bar one will also let you concentrate on one rad and its feed pipe work at a time.

For metallic sludge a piece of plastic pipe with a speaker magnet, or similar, on the outside. However most of this probably collects in the radiators so remove radiator, take outside and use a hosepipe.

on 09/02/2019, snipped-for-privacy@gmail.com supposed :

Something like a fine mesh presently a large surface area, so it doesn't restrict the flow too much would work for the none metallic particles. Add in a way to bypass it and a couple of valves to enable it to be taken out of circuit easily, to clean it out.

A sieve would work with a rectangular container & silicone. So.. what container?

Mains flushing is possible but added hassle. The system won't drain anywhere downstairs. Even the plastic header tank had a thick layer of rusty debris in.

NT