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ajriding's avatar
ajriding
Explorer II
Oct 12, 2015

converting to 4-season water

I built my water system with everything under the floor, thus out in the cold. I now want to be able to use it in winter, so need to convert some things.
I intend to run as much of the water line above the floor (heated space) as I can, with only the feed line from the tank under the floor, and this will be just about a foot.
#1 What water line can I use that will take freezing with water in the line? I have been told about some red line from Home Depot. My current line is the white flexible plastic housing that is about half inch.

The second part is moving the water pump to the heated space which will put it about 2 feet above the water tank. I know the pump can "pull" water, but typically how far can it pull? and how high can it pull from? I say typical since I am not listing the specific water pump.
If I move the pump inside then I want to be able to catch any leaks. Has anyone done this?

For the water tank, 40 gallons, I intend to install a heating pad, but am rarely hooked up to power or running the generator, so am open to ideas to keep it from freezing.

4 Replies

  • PEX = polyethylene cross linked, it is the red pipe someone told you to use. The pipe does perform better in freezing weather but the fittings won't be expanding so will be the first to break from freezing.

    Typical small diaphragm pumps will pull around 10' of head. Depending on ambient temps, the tank will start to freeze before anything inside. Using electrical heat tapes/gutter cable/tank heating pads and enclosing the tank with insulation will work if you have power available. Just insulating the tank will stave off freezing for a few hours. Recirculating water back into the tank will keep the tank water liquid until, probably, -15f. Installing a tank inside the cabin is easiest to deal with.

    The other edge of this sword is how are you going to keep drain water liquid to dump? You may have liquid in the supply pipes but find that your drain tank is solid or break a drain pipe. In Georgia, these measures are less critical. In the Upper Midwest, a cold snap can get everything solid in hours.
  • I was told by an RV tech that manufactures have been using "PEX" line for the last few years in all new builds as it will expand 2-4 times Its size before rupturing. Not sure if "PEX" is the correct spelling, though.

    As for a water tank below the bed not freezing, I've seen it happen on more than a few occasions. Now, the temps were down to -15F and the trailer was not a four-season trailer. We even left the access door open to no avail. This was in my dad's TT, which he bought in Baton Rouge many years ago, so now when we go hunting he doesn't put any water in the tank as a precaution.
  • If you have the space under a bed, consider moving the freshwater tank to the inside. Don't know how that would work with the fill inlet you have, but it would remove the whole question of freezing.

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