Vacuuming out the water lines

The contamination from the compressor will be nowhere near the contamination you get from water sources of unknown origin when camping in other locales.

I learned the hard way to ALWAYS use a whole house filter when using water from other areas. In 2009 I got sand in my water system at Fort Wilderness in Orlando, FL. I never got it all out. There was still some in there in 2017 when I traded off that MH. I don't filter the water in my new TT at home, but anywhere more than 50 miles from home, I ALWAYS filter.

I have never winterized but I do like the idea of vacuuming the water out. OK maybe my thought is more trying to avoid contamination from running the air through a compressor or adding the jug of pink.

No sense trying to reinvent stuff when the proven methods are inexpensive and last forever.

It difficult to answer the question without knowing how much vacuum the vacuum can produce. How high can the vacuum lift the meniscus from a tank of water in a pipe of similar diameter to what is in the RV? As mentioned before, the ability of the vacuum to vacuum will depend on the local atmospheric conditions and be different at different elevations.

No way would I apply vacuum to the water pipes. They're not designed for it and vacuum can be amazingly destructive.

Rather than reinvent the wheel, I would just spend $10 on antifreeze and be done with it.

I have BLOWN them out (50 PSI regulated, 150 PSI 6 Gallon compressor) many times. but never Vac them. DO have to vac the fresh tank, since the idiots put the drain in the wrong place.

Just use either RV anti freeze or low air pressure 30psi and be done with the processs. Vacuuming is likely to open up a can of worms..

Both above methods are tired and true and see no need t9 risk damage to RV lines , fittings etc by applying suction on 5hings meant for positive pressure.

naturist wrote:
Maximum possible pressure to move the water is 15 psi and that’s at sea level. That will be less effective than an air compressor at 80 psi. Might work, though. Give it a try and let us know how it works.

You don't need anywhere near 80 psi to blow out water lines; around 5 psi (about 138 inches or 11.5' of water) would in theory suffice for most any RV.

A shop vac on the blower setting, if one could adapt it to the water inlet and had a good enough filter to keep dust and debris out of the pipe, would probably work just fine. I don't know what the maximum static pressure they develop is on the blower side, but they do produce a large volume of air which is a big help in blowing out the water lines.

Suction could work as well but rigging up a suitable adapter for e.g. the low point drains might be rather tricky. A shop vac does work very nicely for removing water from residential toilet tanks and bowls if one needs to winterize a residential water system. (You remove the water and then put some antifreezing solution in the trap of the toilet; if the water isn't removed from the trap, the antifreeze gets diluted a fair bit.)

Maximum possible pressure to move the water is 15 psi and that’s at sea level. That will be less effective than an air compressor at 80 psi. Might work, though. Give it a try and let us know how it works.