So I filled the fresh water tank today for the first time. Actually over filled it. Water came out of the overflow drain line as expected and continued to flow until the fill pipe was empty. But another blue drain beneath the trailer continued flowing for a considerable time - perhaps 15 minutes. The tank gauge indicated full directly after filling . After the blue drain pipe stopped flowing the tank gauge showed only two thirds full. So what is this extra blue drain pipe exiting beneath? There are 5 drains. Hot water line (with valve at the terminus), cold water line with valve, fresh water tank drain line with valve, white overflow line (no valve) and blue line (no valve).
2012 Redwood 31SL chasing 2019 Denali HD 3500 Duramax SRW