I live in a row of townhouses with a common, CI main drain. Nearly all, if not all, units have HE heating units that dump condensate into that drain. None of them have any pH neutralization treatment on them. How risky is this? And, if treatment is needed, is it better to try to do this for the building (in the order of 10 townhouses), or individually. Hassle is, trying to enforce it on even any one individual when you don't have access would be a problem. My concern is that over night, when the houses are the coldest, there would be little to no flushing of the drains by people flushing toilets, or other water flow that might dilute things. Probably, during the day, it may not be as big a problem. The interior drains are pvc, it only becomes CI when it gets to the main which runs between units and out the end. Thoughts?