Thor Forums

[EA37TS]

Third motorhome in ten years and all three had a black tank flush system. I have never winterized the black tank flush and have never had anything freeze even when temps got down to -15 degrees. I do however, blow them out with low air pressure when I de-winterize the coach making sure there are no issues before connecting a water hose.

I did have a vaccum breaker fail but that was in the middle of summer and the failure was the breaker would not open to allow water to flow into the tank.