Yes we do and that is what I used to winterize. There is a shut off valve on the line from the fresh water tank just before it goes into the pump. Block that line and the pump picks up the antifreeze from the line to that external fitting. Two bypass valves at the hot water heater that have to be blocked and a third valve between the hot and cold water lines opened (also at the hot water heater) and that's it. Took 3 gallons.
Randy and Patty
2015 Sabre 33 CKTS-6 Platinum Edition
Reese 16K Slider hitch
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