OK, few years back I decided that compressed air is the way to go... So I set the unit up and BLEW AWAY... No pink "stuff" required... until the Spring when filling the fresh water system I had water running out on the ground!
Seems there was a low point in the Aqua Hot loop and moisture collected in the low spot (after the lines were blown out) and broke the connection!
For me, IF I have to winterize it will be RV antifreeze in the lines... and BTW, if you're putting RV antifreeze in why are you wasting your time with air?? The Pink stuff displaces the H2O... Best plan is to head south!!
Ken & Anita
2011 Newmar Essex, 45'- 4522, Cummins 500 ISM, 2013 CRV, RVI2 Brake with TPMS