I've decorated a few rooms recently which has involved the draining
and removal of radiators. I'm just

about to put the last one back on, however before I do this it struck
me that I've probably diluted the

inhibitor. The towel rail came off a couple of times due to a leaky
TRV.

I know the best approach would be to drain the system and refill
adding inhibitor. I haven't drained

this system before (moved in earlier this year) and November doesn't
strike me as a good time to start

experimenting with ways to clear airlocks.

The previous owners left no indication of what type of inhibitor may
have been in the system.

My question is, am I safe to add more inhibitor in to the system
without draining down?

TIA

Marc