Help with plumbing

[thompsondr1]

I’ve spent the last few days taking stock of my new (to me) 1978 Sovereign. I’ve been trying to leverage the other posts here (and am a newbie) but still have some questions I’d love help with. Please forgive the number of questions but I thought it was more efficient to gather them in one thread versus a bunch of individual ones (and please excuse my ignorance of plumbing terminology).

Picture 1 (Black.grey connection) – We are going to use a composting toilet so I was already planning to combine the two tanks. Today I tested the tanks and neither leak…but the Thetford valve leaks on the black tank. Should I just cut all this out, make a T connection out of pipe (connecting the two tanks and then flowing out) and then put a valve on the outside of the Airstream (so if it breaks I don’t have to pull apart the belly pan to fix it)? Do these tanks have any specific threading on them? Anything else I should watch out for? I have 22 and 26 semi-opaque tanks. Any reason I can’t use SeeLevel monitors on these?

Picture 2 (Fresh water) – I think I’ve identified everything here but please correct me if I’m wrong. After the water goes through the pump it goes into the copper pipe which has a T going to “mystery section” (question on that in next pic) and other side coming in on left of pic. It splits to the spigot, behind which controls a 4 inch tube going out the trailer. I assume this is the fresh tank drain(?) Would it not make sense to move this outside the trailer for ease of working on it and so I don’t to leave this section exposed? The yellow continues to the red outlined plastic pipe and looped around to feed the hot water heater (I think).

Picture 3 (Mystery copper pipe) – As mentioned above, this comes out of the water pump, does some zig-zagging and then goes to the outside of the trailer and is capped right behind the dump valves. Any clue what this is and do I need it?

Picture 4 (Bent gas line) – I inspected the whole gas line and it nearly all looks good (no bends/cracks) and I plan to use the soap test. That said, these bends are about 1 foot from where is starts down the A part of the trailer frame. Any reason I can’t just cut it here and replace the short section between here and the tank? Seems like it would be a waste to pull out the whole thing if this ends up being the only compromised section.

Not pictured – Currently my fresh water inlet is just a hole in the side of the trailer (i.e., no threaded screws). Should I replace it with a threaded one? I was just wondering if there were ever issues running into hoses without threaded ends (or in a pinch from plastic tanks). Also I was wondering how to know when it’s full (if the tank monitor is inside)(?)

Thank you all so much for your help! I really appreciate it and definitely couldn’t do it without you!

Ryan

[TheGreatleys]

1. Vintage Trailer Supply sells replacement Thetford valves and repair kits. Don't rip it all out if you don't have to. If everything else is good, I'd just replace the valve.

SeeLevel monitors will work great. You need the "junior" senders (shorter ones).

2. Anything you move to the outside of the trailer is susceptible to freeze damage, so I'd keep any water pipes and valves inside the heated envelope if possible.

3. My city fresh water connection was at the back by the dump valve. That sounds like what you're describing, and it may have been capped off because it broke.

4. Yes, you can cut out and replace just that section. Just try to keep all of your joints in the gas line outside of the trailer. Old gas lines sometimes do get gunked up over the years. I replaced all of my gas lines while I was redoing everything else. It's really not that much work. But yes, if everything else is in good shape, you don't necessarily need to replace it all.

5. Your fresh fill should be a gravity fill. You need air space around the hose for air to escape, so you don't want a threaded fitting for the fill. You'll know when the tank is full because the sound will change (like how a the sound of a glass of water changes pitch as it fills), and if you don't stop, water will back up the fill line and spill over the side of the trailer.

[Bill M.]

Me, I would replace both waste valves and leave the original setup. Then if you want to use both tanks for gray water you can add one of the twist on valves to the hose connection and connect the 2 tanks by opening the valves. And the trailer stays usable for normal use.
On the water inlet: you do not want a threaded connection. That kind of setup will blow up the tank from water pressure. I check the tank monitor inside when filling the tank and stop around 3/4 so that the water is below the inlet hose level.
I would not consider replacing a whole gas line a “waste”.
I have no idea what the water line is for. I would replace all the water lines with PEX and run them where I wanted them. I would not run an outside faucet from the trailer.

[thompsondr1]

This all makes a ton of sense. I also now get the distinction between city water and fresh (I had seen that on new trailers but since mine didn't have a city water intake labeled as such I had not researched it). The gas line certainly doesn't look new so I'll play it on the safe side and replace that as well. Thanks again!