HELP with flushing system overnight?

JeffGuy

I've gotten advice here on a boiler install (for which I'm most grateful), and need advice for flushing my radiator zone on an old gravity system. I'm installing a stainless mod-con and need to get as much crud out of the system as possible.



We added temporary couplings and hose connections to the supply (at top left), return (bottom after the circulator), and water supply (top right). Before we added the circulator we ran it for about half an hour and the water coming out of the return was clean, but then when we drained it down it was looking pretty murky so I figured it needed a better scrub, maybe with a circulator pump this time to cycle it?



If this was your setup, what would you do to best clean it up? I have 16 hours to work with.



<a href="http://s929.photobucket.com/albums/ad132/4more/Boiler/?action=view&current=HPIM1696.jpg"><img src="http://i929.photobucket.com/albums/ad132/4more/Boiler/th_HPIM1696.jpg" alt="" /></a>



Thanks!

Jamie Hall

The good news is...

that you may not have as much of a problem as you might think -- but I would surely install a Y strainer on the system before the water gets back to the nice new boiler.



The bad news is that to get much of the crud out, you will have to get the velocities pretty high, and in a gravity system with its big pipes you may have trouble doing that.  However, if you pump it or circulate it at two or three times the max. your new system will pump, that should get a lot of what needs to get out, out.

JeffGuy

Lots of dirt eaters

I'm installing two Y strainers on the radiator zone plus a spirotrap on the boiler return so I'll have plenty of chances to collect whatever's left. I'll have more invested in dirt collection than I do in circulators. But I want to get out as much of the dirt as I can now, especially since the Y strainers aren't easy to flush out.



I got advice before to make sure I flush the system really well, and this is my chance to do it. But it isn't as easy as it sounds, and I couldn't find any advice on what to do. The circulator I have on it (007) was used before and was enough to heat the whole house, but it won't do more than the new circulator.



When I run water through the system it comes out looking clean, though it is dirty when it drains down.  Maybe I should just partially fill and drain a couple times?