Update, leaks and spray in foam ugggh!!

[Bex]

OK, so where to start.
I had a plan, start with re-sealing all windows as per Andy (and others) suggestions.
Now what to do whilst I wait for seals and other items to be ordered/sent.
Re-check the floor in the rear, lino is curled, sure sign of moisture. Sure enough, floor is rotten in a small section, not sure if its condensation (as PO's son suggested) or from the outside.
Pulled half the floor to expose a section at rear about the size of a pea where water has been coming in.
At the same time, checked the frame, it's got some rust but not needing anything replaced.
Create another shopping list:
POR 15
Aluminum sheet (some panels could be replaced)
Rivets, nuts, bolts
Ply.
Need to run new water line to outside, anyone that recalls me asking "what's this" in a previous post? Well, it was a hole punched through the interior exterior to make way for a 3/4 inch galvanised pipe for Town water supply. It poked out the side a good 6 inches. How it never cought on anything I really do not know. Whilst disconnecting the battery to remove outlets from the interior skin I noticed a bunch of spray foam insulation in the wheel well area almost completely covering two shut off valves for the (still copper) water lines. I guess I need to remove the belly to access these lines for replacement. Thats a job for this weekend. As well, the copper pipe to be replaced.
Anyone got a water plumbing schematic? I might post this question elsewhere but whilst I am here, would I run 3/4 inch inlet (Town) Pex then reduce to 1/2? Is there any need? If so, at what point do I reduce it.
Anyway, I will update again later when I have done a bit more.
Cheers

Bex

[Argonaut20]

Unless someone has 'modified' it, the water lines are above the floor. Depending on where things are placed, they may run under the shower pan, but above the floor. Less chance of freezing. I have the city supply, water heater, and pump on street side, then branches to all the other stuff. Most of the branches are 3/8.

1/2 inch line is good for the main line from the city feed and pump, but 3/8 usually works for appliance feeds. The brass pressure regulator, check valve, and pop off near the city inlet need to be braced if you use pex and the slip on fittings.

[Bex]

For sure it's been modified then, they run under/across the trailer from the wheel arch (curbside), to the center bathroom on the street side.
So perhaps what I need to do is run them in to the pump, then back around the back of the trailer (along the same side) and into the bathroom?

Bex

[Argonaut20]

If the pump is on the street side, then think of a line from the street supply to the pump as a sort of 'trunk' line with a check valve on either end (check valve is usually in the pump on that end, a separate fitting after the street supply). Everything branches off that line to go where it needs to go. Hot water is a separate feed out of the heater that you branch off to the points where it's needed. I don't know how your Argosy is laid out, so I am pretty general here. If the kitchen is on the curb side and the bath is on the street side, for example, you will likely run hot and cold supplies around the back of the trailer to avoid crossing the doorway. There is usually plenty of area to run the water lines what with beds, gauchos, built ins, etc along the walls. Tie pipes to the floor or the wall to keep them in place.

[Bex]

Thanks!
My next question is how does that all tie in with the freshwater tank? Is it "just" through a tee into the the same line to the pump?

Bex

[Argonaut20]

The fresh water tank has a flexible line to the pump, then the 'trunk line' comes out of the pump. That way, if you are hooked to city supply, the check valve at the pump keeps the water from running into the fresh water tank. If you are using the fresh water tank and pump, the rear check valve keeps the water from draining out the hose connection. It might do to think of the 'trunk line' as running from the city supply hose connection to the fresh water tank with the pump inserted near the fresh water tank and a check valve inserted near the city supply, before any branching for various supplies are done. All the branches are between the pump and the rear check valve. The pump acts as the front check valve as it usually has a check valve built in on the outlet side.

[Bex]

Perfect, thanks
on another post I submitted a diagram that I found elsewhere (from an Airstream shop manual, apparently) and have tried to understand it but without success.
What size lines should be run from the City and tank to the pump, then around the trailer and finally to the outlets?

Bex

[Argonaut20]

The trunk could be 1/2 inch pex, tee off whatever size the water heater needs for supply, use either 1/2 or 3/8 for the rest. I used 3/8 to distribute the water to where it was needed, but my Minuet is small. I find I have plenty of water wherever with the 3/8. I kept the copper inlet for the city as I kept a pressure regulator, check valve, and pressure relief valve at the rear. I then went to pex for the trunk and used 1/2 inch there. I can't recall what I had to use to supply the water heater.

[Bex]

OK then, with the info I have from my other post I think I am set.
Guys, my sincere appreciation and thanks for the input.

Bex

[BigAl]

Just for your information, half inch copper pipe is half inch inside dimension, and pex is half inch outside dimension.
That is a really big difference!!!!
Al

[Bex]

What difference will the internal diameters make to water flow in the trailer?

Bax

[Argonaut20]

I can only speak from my experience using pex: I have more than enough water flow at all points. I don't use two faucets/shower at once as a rule. 1/2 and 3/8 work fine for me.

[Bex]

Cool, thanks!
Bex

[Bex]

OK, so yesterday and today I replaced 90% of the plumbing, with success!
The bits I left alone were the tank to pump and the bathroom copper connections to the faucets. There were plastic tubes to the toilet and toilet sprayer so I left those alone too. Incidentally, I am not sure if its standard or not but there is a gizmo between the cold water line running to the bathroom faucets and the toilet spray, it appears to be a stop valve; it prevents water flow when the spray is off, I suppose it relieves pressure on that little plastic spray fitting. I decided to leave it in place.
There was copper running under the center of the trailer and I am not really sure if that was original or not. I could not figure how to get at it easily so I left it there and ran pex from a tee off the hot water tap outlet on the water heater, right back around the rear of the trailer and into the bathroom. It all works and will be hidden when I rebuild the bed in the rear. I also installed a new Town water inlet using the hole a PO had (literally) punched through the skin og the trailer and poked a piece of galvanised pipe through (about 7 inches) with hose connector attached. Functional, but not to pretty.
Anyway, tomorrow is a bit of clean-up, install two drains for the water system, install new shore power connector and remove the old copper pipe that I can get to without pulling the trailer apart.
Before I did this the only DIY I ever did was...........nothing, not a single thing that I can remember. Three months ago I was not even looking for a trailer. I have actually spent more money on tools that supplies and the trailer put together (well, almost).
My thanks to all that have responded to my various questions thus far. I do have another question pending concerning the waste tank access and hope to get to that next week as well.
I can't wait to retire, work is starting to get in the way.

Bex