"[b]"Some boaters at the c
""Some boaters at the club tell me they also pump compressed air to chase out the antifreeze from their water systems as well."
Frank, are we talking about O/B water systems?
And do you mean "blow the water" from the system?
These guys have been very lucky so far if that is what they are doing!
To me, this is another common misnomer, and again, these are just my opinions from having been doing this for many years!
(hydraulic and pneumatic principles)
Air pressure, in a line/hose, will not sufficiently displace or move liquids out of a low point, for example unless you can provide extreme volume.... and volume will usually be accompanied with pressure...... and that is an issue due to size, distance and potential burst pressure considerations for water system lines!
The air may move it temporarily, but the liquid may fall back into the low point!
Now we have a cracked low point fitting, line or ???? when it freezes!
Liquids will move liquids very sufficiently!
Best to drain the tank and add a few gallons of RV stuff to your water tank, and run it through the system until we see it come out at each fixture.
Some owners will create a by-pass valve(s) at the WH so that it can simply be drained.
(saves on the amount of antifreeze as well)
When in by-pass mode, your system provides flow through all remaining parts of the system.... pump, hot and cold fixtures... but not the WH.
I suppose the best of both worlds would be to blow first, then add the antifreeze and let it run through the system.
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