Routing Water Lines

[Carl Brooks]

Howdy y'all,
Today I'm working on water lines in my lil love bug and several questions have popped into my fiberglass clogged brain.

Just how were the water lines run from under the sink to the water heater? Somehow I don't think holes thru the floor with bare 3/8 copper tubing running under the trailer is a factory build.
Was 3/8 the size used or should I consider going to 1/2''?
I'm planning on using stainless steel flex lines or would that be a bad choice? I can't think of any reason why they wouldn't be a perfect choice.

Inquiring minds want to know.
Carl

[tractors1]

Most, if not all, of modern plumbing AND trailers is done with PEX brand plastic tubing and either PEX connectors (takes a special crimp tool) or Shark brand fittings. You can play with these at the local big box (Loews, Home Depot.) One of the big advantages is that PEX has more expansion tolerance for freezing water in the lines without splittlng. Also good for hot or cold. WAY easier and cheaper to route than metal and has better flow rates because it's so smooth inside. I don't think I 've seen any in trailers with over 3/8 ID (fits standard plumbing connectors.)

Charlie Y

[Carol H]

Originally Posted by Carl Brooks

Just how were the water lines run from under the sink to the water heater? Somehow I don't think holes thru the floor with bare 3/8 copper tubing running under the trailer is a factory build.

I am assuming our hot water tank is also inside the tailer? In that case most fiberglass trailers have all their water lines and connections running inside the trailer. Normally around the bottom inside edge of the trailer to get to where ever the water needs to get to.

[tractors1]

Are you sure the external lines aren't the propane feed for the water heater or furnace?

[Bob Miller]

After 40+ years, hard telling what has been added and/or changed. I don't know what a 1973 Tri-Fab even looks like, but almost all of the earlier FGRV's were sans water heaters from the factory and yours may have been added in or at least changed out by a previous owner.

I have installed three water heaters in the past 2 years in FGRV's and in all cases I used PEX pipe & fittings and ran same inside the trailer. Besides the increased possibility of physical damage, water pipes run external to the trailer are at greater risk of freezing in cold weather.

Flex lines are tempting, but long lines may move around enough during travel to promote premature seal failure at the swivel ends. Most were intended for fixed, non-moving, applications except, of course, for those we have here in California where earthquakes keep things moving on a daily basis. I sometimes use flex lines from a secured PEX transition to metal fitting to a faucet, but they are usually no longer than 12"

[Robert Johans]

Totally agree with the above endorsement of PEX wherever possible. However, I would not fear the stainless IF they provide some ease to the install AND you keep the lengths short.

As to copper lines, kinda doubt that they are water lines, but I've sen some strange set-ups...

[Carl Brooks]

Originally Posted by Carol H

I am assuming our hot water tank is also inside the tailer? In that case most fiberglass trailers have all their water lines and connections running inside the trailer. Normally around the bottom inside edge of the trailer to get to where ever the water needs to get to.

Yes. Factory LP/Electric water heater inside trailer.

[Carl Brooks]

Originally Posted by tractors1

Are you sure the external lines aren't the propane feed for the water heater or furnace?

That's run on a 3/8 copper line also, right next to the waterlines.

[Carl Brooks]

"After 40+ years, hard telling what has been added and/or changed. I don't know what a 1973 Tri-Fab even looks like, but almost all of the earlier FGRV's were sans water heaters from the factory and yours may have been added in or at least changed out by a previous owner."


This is what I'm learning as I get more into this labor of love. It looks just like a Boler with minor differences. Tail lights, windows. It also has a shower and a potty built in.
An A/C was added in the back on the floor so I'm guessing that's why everything has been rerouted underneath.

[Reid Larsen]

I had a plumber help me plumb a '78 Trillium w/ pex a couple of years ago and when I ask him to help with my newer 79 that I have installed a water heater and pump and outside shower in he suggested brass fittings and stainless flex lines to plumb the whole thing. Have only used the trailer a couple of times since doing the plumbing but it works flawlessly. My plumber friend mentioned that if you have a pex fitting leak on the road you are in trouble but any plumbing or hardware store will have stainless flex hoses to make any repairs necessary- not that he thought they would fail. YMMV

[Jared J]

IIRC, home code around here requires 12" of metal line on the water heater output before pex is used, due to deterioration. I used copper flex line.

[Carl Brooks]

Originally Posted by Reid Larsen

I had a plumber help me plumb a '78 Trillium w/ pex a couple of years ago and when I ask him to help with my newer 79 that I have installed a water heater and pump and outside shower in he suggested brass fittings and stainless flex lines to plumb the whole thing. Have only used the trailer a couple of times since doing the plumbing but it works flawlessly. My plumber friend mentioned that if you have a pex fitting leak on the road you are in trouble but any plumbing or hardware store will have stainless flex hoses to make any repairs necessary- not that he thought they would fail. YMMV

Reid,
That makes a lot of sense. I believe I will go that way.
Thank you.

[Carl Brooks]

Went with PEX. Easier to work with.