In article 240e3208-f077-474f-964a-3c59f58e0a30
@q26g2000vby.googlegroups.com, says...

I think my system is clean.

I put twice as much inhibitor as is needed in there when I last
drained down the system.

Only clean water comes out if I bleed the radiators. Never anything
other than that.


In that case just ask your installer to do a normal flush prior to
installing the boiler. In my son's case, the plumber visited two days
before fitting the boiler and put some flushing stuff into the system
and then drained that out when he did the actual installation.

--
Kev

Justice? You get justice in the next world,
in this world you have the law...
William Gaddis