Winterizing - Extreme cold winters

time2roll wrote:

Kayteg1 wrote:
Compressors are inefficient.
Get shop vac and let it run for 1 or 2 hr to blow the piping dry

Ever vacuum the water out?

Not from an RV, but I do have a good friend who uses a shop vac to winterize their cabin, vacuuming out the excess water from the toilet tanks and bowls before putting antifreeze in.

Growing up we had an apartment above our garage that would get winterized, and we used a plunger to get as much water as possible out of the toilet traps, but the vacuum is quicker and easier and more thorough for that. Of course, in a standard RV toilet, this is not something that needs doing.

For the supply pipes, though, it's not at all necessary to get every last molecule of water out. A few drops remaining don't cause problems, in my actual experience. Blowing out the lines doesn't need to take hours to be effective. (Of course, displacing water with antifreeze is also effective.)

I don't know if most shop vacs would develop enough pressure to push the water out or not, though if used in suction they should be sufficient in my estimation. Rigging up an adapter from vacuum cleaner hose to water inlet or low point drain seems to me like it would be a bit tricky.