Why not just open a valve , rather than getting wet hands on a cold day when you must drain a line or the fresh water tank? I installed a valve on each line as well as my fresh water tank. A friend told me of this at a rally. I'm just pass it the hint along - with a pic. I bought the valves at Ace. Take a drain cap along for sizing.
Alan, Kathy & Cooper the camping cat
2014 Cedar Creek, 36CKTS
2013 GMC 2500 Denali
Full timers since 5/30/2013