Assuming that the lines are full of RV antifreeze. You will need to flush them for several minutes ( pink should be gone ), but not to worry, it's not poisonous, open every valve for a minute or so, including toilet.
They may have left low point drains open. They will need to be closed, along with fresh water tank drain point. They may have also left the antifreeze intake hose valve open ( next to water pump that will need to be closed and the valve for the pump to fresh water tank opened, if equipped )
Your fresh water tank should be sanitized. Search forum or internet for exact process, but involves adding 1/2 cup of bleach mixed with 20 gallons of fresh water and allow to stand for hours; drain, fill, drain.
If you did not have antifreeze in pipes, then before your drain from step above, pump some of the bleached water into your pipe and let stand as well, flushing several times afterwards
Last, and after you have drained bleached water, If you have hot water bypass valves, they need to be set to normal positions.
Connect to fresh water ( hose or filled tanks ) and open hot water side of tap, allowing water to fill hot water tank. You may also want to open air purge valve on hot water tank to purge air.
Jim & Kim from Colorado
2014 Eagle 30.5 RLS
2015 Dodge 3500HD SRW 6.7L
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