Your rig should have a fresh water drain built in, along with drains for the water lines. You may have to search for them. Check in the wet bay, and under the fresh water tank, on both sides of the rig.
2006 Damon Daybreak 3276 35'with 5 Star Tuner. 3 200 Amp Lithium batteries and 2000 watt PSW inverter/charger. 2013 Elantra on a Master Tow dolly.