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The two drains next to each other are the low point drains. One is for the hot side and the other is for the cold side. The fresh tank drain will be a single drain and located underneath the fresh tank.
When you winterize, you can open the low point drains and then open all the faucets and the water will gravity drain.
You don’t have to completely drain the tanks, but think of them as big ice cube trays, the emptier they are, the more room for the water to expand when/if it freezes.
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2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.