rust inhibitor

[Spreeny]

My central heating system has been drained & refilled but without any rust inhibitor, I've bought a can but I'm not sure what to do.. Do I drain the same amount of water off & add it all in one go to the top of a radiator ? Please can anyone help.....

Thanks in advance

[gucciman]

what type of applicator did it come with? some come with a nozzle that allows you to inject it into the system through the filling loop using a sealant gun, this is my preferred method.(im presuming you have a combi boiler, if you have a traditional system with tanks and cylinders you add it to the central heating header tank then drain some out so it gets down into the pipework)
and yes if its a combi and your adding a litre of inhibitor then drain a litre of water out first and then add through the filling loop, you can also inject it into the bleed nipple or you can take a rad off the wall and pour it into the rad.

[Spreeny]

Yes it is a combi boiler & thanks very much for your help..