Keep Low Point Drains From Freezing

[nomad297]

Many RVs have no way of protecting the low point drains protruding from beneath them from freezing. If you’re lucky, you have valves in a conditioned area of your RV that you can turn off, leaving the protruding part of the drains empty so they won’t freeze and burst, but many RVs don’t have these valves — they just have caps at the end of the drains that will cause water to be held in the protruding pipes making them susceptible to freezing and bursting. This is how my low point drains are.

My solution for this was to use a tool I use almost daily for plumbing. It is called a Jet Swet, and it is about a foot long. Its real purpose is to plug a water line to keep water at bay so work can be done without residual water in the lines causing problems while you work. It is impossible to solder a copper joint if the slightest amount of water is in the line.

The Jet Swet can be used to plug the low point drains about one foot above where they protrude from the bottom of the RV, making them less susceptible to freezing and bursting. You can use them as your permanent low point drain plug or you can just use them when you will be camping in freezing temperatures. Here is a picture of a 1/2” Jet Swet to give you an idea of how it would work:



Bruce

[SeaDog]

Seems like a neat product when I had my construction firm many times we used white bread stuffed in the end of a copper line to stop water for soldiering. I installed valves on my rig in the low points.

[nomad297]

Originally Posted by SeaDog

Seems like a neat product when I had my construction firm many times we used white bread stuffed in the end of a copper line to stop water for soldiering. I installed valves on my rig in the low points.

The problem with using bread is, it won’t hold back the water when it is leaking through with pressure behind it.

I don’t have an accessible location for valves in my RV. I wish I did.

Bruce

[SeaDog]

I was not saying use white bread (no seeds) on an RV I was saying when I was putting copper together that was the method I used (years ago). The bread gets blown out when pressure restored. I like the tool you mentioned

[nomad297]

Originally Posted by SeaDog

I was not saying use white bread (no seeds) on an RV I was saying when I was putting copper together that was the method I used (years ago). The bread gets blown out when pressure restored. I like the tool you mentioned

I understood what you were talking about. It is an old trick that can work if you are only fighting against residual water in the lines, but if you’re dealing with water in the line that is there because a valve won’t shut off completely, the water will keep pushing past the bread dam.

Yeah, that tool is the best thing since sliced bread. Pun intended.

Bruce

[mykie64]

I usually wait until the antifreeze comes out of them then I'll put the caps back on.

[babock]

Originally Posted by mykie64

I usually wait until the antifreeze comes out of them then I'll put the caps back on.

I could be wrong but I think the OP is concerned with them freezing while camping I believe.


Personally, I never worry about that since my low point drains are a very short distance from where the pipes are in my conditioned space. If the water in the couple inches of PEX freezes, it's not the end of the world.


I did just buy a set of the tools though. I have some plumbing to do in a week so they will be perfect!

[nomad297]

Originally Posted by babock

If the water in the couple inches of PEX freezes, it's not the end of the world.

But if it bursts, you’ll have a mess on your hands and an empty fresh water tank.

Bruce

[Griff02]

That is a great thought. I don't camp in a really cold region, but we have camped when it dips down into the 20's, and I never even considered the low points. I would disconnect the FW hose and run on the FW tank, but the low points would still be fully exposed. Guess I've been lucky, but I won't leave it to luck anymore. Thanks for the reminder, and a solution.

[babock]

Originally Posted by nomad297

But if it bursts, you’ll have a mess on your hands and an empty fresh water tank.

Bruce

First off, low point drains are after the pump. Second, if they freeze, they will just expand up into the area where the climate is conditioned.



We have camped in 17 degrees and never had an issue.


Next time I am in that weather, I will pull the caps and see if water flows out.

[MR.M]

That's kind of an expensive fix Well not a fix a cover up . I have my low point drains cut short and a brass ball valve on to open when needed . if you can keep the water lines from freezing chances are the little bit that sticks out from the underbelly for the low point drains will not freeze or freeze solid enough to break the pipe . bass can't expand but the pex can a bit . It has never been an issue for me spending too many nights below freezing and even having the rv parck supply freeze but never the low point drains

[Scubanut]

Originally Posted by nomad297

Many RVs have no way of protecting the low point drains protruding from beneath them from freezing. If you’re lucky, you have valves in a conditioned area of your RV that you can turn off, leaving the protruding part of the drains empty so they won’t freeze and burst, but many RVs don’t have these valves — they just have caps at the end of the drains that will cause water to be held in the protruding pipes making them susceptible to freezing and bursting. This is how my low point drains are.



My solution for this was to use a tool I use almost daily for plumbing. It is called a Jet Swet, and it is about a foot long. Its real purpose is to plug a water line to keep water at bay so work can be done without residual water in the lines causing problems while you work. It is impossible to solder a copper joint if the slightest amount of water is in the line.



The Jet Swet can be used to plug the low point drains about one foot above where they protrude from the bottom of the RV, making them less susceptible to freezing and bursting. You can use them as your permanent low point drain plug or you can just use them when you will be camping in freezing temperatures. Here is a picture of a 1/2” Jet Swet to give you an idea of how it would work:



Attachment 224220



Bruce

Love the idea “but on amazon.ca there asking over $200 for 1.

[NJKris]

Cool idea. I've just put some pipe insulation foam with a little duct tape on the slit over them. Camped down into 20s with no freeze issue. At 52 bucks on Amazon and you need two, I'm sticking to pipe insulation.

** I re-read post and noticed you already had it for other plumbing jobs. Good to be friends with plumbers!

[Tapex]

Originally Posted by NJKris

Cool idea. I've just put some pipe insulation foam with a little duct tape on the slit over them. Camped down into 20s with no freeze issue. At 52 bucks on Amazon and you need two, I'm sticking to pipe insulation.

X2

[Oafdawg]

Originally Posted by nomad297

Many RVs have no way of protecting the low point drains protruding from beneath them from freezing.

Bruce

The Pex will just freeze up to the point where it's warm, or up to the point where there's antifreeze or blown out with no damage. To prove that take a piece of Pex, cap one end, fill with water and place outside in the winter or put in the freezer. Even capped at both ends odds are it won't split.

https://youtu.be/g6LHbljuF6U

[babock]

Originally Posted by Oafdawg

The Pex will just freeze up to the point where it's warm, or up to the point where there's antifreeze or blown out with no damage. To prove that take a piece of Pex, cap one end, fill with water and place outside in the winter or put in the freezer. Even capped at both ends odds are it won't split.

https://youtu.be/g6LHbljuF6U

Exactly what I was saying.

[NJKris]

That video was a good experiment.

[nomad297]

Originally Posted by babock

Exactly what I was saying.

One of the few things I use Shark Bite fittings for is frozen and burst PEX run outside under decks to hose bibs. It does burst/split when it freezes. It may not burst every time it freezes, but it does burst quite often.

Bruce

[MR.M]

Why do people run any length of pipe under a deck in places where they get freezing weather If it can not be shut off and drained before winter ? most hose bibs are 12" to 18" stubbed out from house that self drain when shut off .

[NJKris]

Mine runs about 12 feet under deck. I turn off valve in basement, and open bib on outer edge of deck before freeze, never had an issue. I don't know if it is sloped enough to drain, as I don't see much water drain out after shutting off inside valve and open outer bib.