by chris_on_tour2002 »
Fri Jan 15, 2010 12:04 pm
quite common for heating water to look dirty when draining. it's not that much of a problem (or unavoidable at least) if there is no sludge, sediment or gritty material.
if you've drained it down and refilled then that will have flushed it. i'd be inclined to drain down again and refill. add a good quality inhibitor such as fernox, if not gunked up then system cleaner should not be necessary, a flush and refill with fernox should be sufficient.
depending on the age of the system and when it was last flushed would determine whether or not to clean is necessary. a bit of a job as you have to add the cleaner, run the system for a while then drain, flush, fill with a neutraliser, run for a while, drain, flush then refill again adding inhibitor on the final fill. still, it wouldn't do your system any harm whether strictly necessary or not.
to add inhibitor to a pressurised system can be done in two ways. if you have a towel radiator in the bathroom then prior to refilling the system i remove the blanking plug and add it in there with a funnel.
if you don't want to drain down again then you can use one of these:
http://www.awin1.com/awclick.php?mid=12 ... -Protector
you pump it straight into the bleed valve of a radiator. this will mean removing a radiator and draining to make capacity but it's better than draining the whole system.
but as i say if it were me, i'd always flush and drain after an initial drain just to help shift as much of the dirty water as possible.
and fernox is generally considered the best brand for any kind of chemical maintenance for a domestic heating system.
