Upgrades - Water heater and 12 volt system

[55AS]

Like most trailers of this vintage, mine came with no 12 volt system and an electric water heater.
In the short term I have replaced the non-functional water heater with a 6 gallon electric model and and the only 12 volt consumer so far is the control board for the new fridge (which I am powering off a small cigarette lighter type plug). This allows me to camp now while on shore power.
To boondock, i will need to do the following:
1. Replace electric water heater with LP model. This will require a cutout in the shell for venting. Logical location is rear street side (under the rear bed). Not excited about cutting the shell nor about the ugly painted door on the Atwood water heater. I guess I will get over the fear of cutting the shell and I can paint the door silver.
2. Since i want a DSI (rather than pilot light) model, I will need to run 12 volts to the water heater. More on this later.
3. Add fresh water tank and 12 volt pump. Logical location is under front gaucho, although plumbing runs will be long and hard to hide.
4. Add a battery, 12 volt converter/charger, and 12 volt distribution panel. This is the hard part to figure out. Ideal battery would be LiIon due to light weight and no venting but a large enough one for extended boondocking is simply too expensive ($1200). AGM battery seems like a good compromise but where to put it and do I vent it?
I understand that placing AGM's indoors is acceptable and no venting is required if they are left open to a large space to dilute any possible hydrogen produced during overcharging.
Option 1: Under the rear bed. This is close to the shore power connection and running wiring to the water heater and fridge is doable. There is no good place for the panel though and I hate to keep adding weight so far from the axle.
Option 2: Under the fridge (curb side midships). Could mount panel in forward wall near the floor and weight is directly over the axle. Concern is possibility of hydrogen gas near ignition source (fridge burner). I suppose one option is to use a sealed battery box vented to the outside but even that puts the gas near the fridge intake panel.

Anyone solved these issues on their early 50's FC?

[54fuselage]

Hi BambiTex, I'm way behind you in the upgrade process but have been doing a lot of research. Like you, I'm not in favor of cutting the shell to vent and perhaps you've already made the cut. If not, there's this solution - precision temp 550 is a tankless heater that has a floor vent. No cutting of the shell, and the floor vent is less susceptible to wind. I've seen the reviews, and some love it and some hate it. My only concern is that it sounds like the company doesn't stand by it as well as they should, but I love technology like this so may give it a try. The idea of having a long hot shower seems to win out, even though this unit isn't cheap.

Also, it doesn't sound like we should be too concerned with overcharging the AGM, if everything is set up properly. I'll be doing everything possible to keep mine close to the axle. It sounds like both locations you have are less than ideal, tough decision. Maybe another option further forward?

[55AS]

Thanks for the reply. I am aware of the precision temp "NSP" (No Sidewall Penetration) model but not sold on it yet. First, they are over $1000. Second, tankless heaters seem to be tricky to use. My previous trailer had a 6 gallon Atwood which cost less than $350 and worked flawlessly. Never ran out of hot water but always staggered our showers 20 minutes or so. The 6 gallon model has a very fast recovery time. Just going to bite my tongue and cut into the shell when I install it:-)
I think an AGM battery under the fridge is the best option due to short wiring runs, optimal weight placement and convenient spot for panel. Sure wish lithium battery prices would drop some more:-)
What model AS do you have?

[54fuselage]

Yes, price is up there and with the tankless models often being finicky it is a gamble. That decision is a ways off for me. Cutting the shell isn't the end of the world, and after its done you'll be able to enjoy it. Hear ya on battery prices too!

I've got a 54 Flying Cloud and have been enjoying all the great threads here. Have learned a ton over the past few months, have been stocking up on supplies, and finally started into the project last month. Shell is off and frame is stripped bare and waiting for the media blaster's schedule to free up. Really overdue with posting updates and I've got lots of things to work through. My plan is to make this almost identical to the design of the Orvis trailer that you've probably seen. Right now I'm designing a dropped rack that will support tanks below and within the belly pan, of which the Orvis trailer has.

[mandolindave]

You could rivet an aluminum plate on to the door and paint the exposed edges silver

[55AS]

Or spring for the $125 stainless door at VTS...

[55AS]

Ended up going with a Suburban water heater that just fits under the bed. Shell cutout turned out ok. Painted white door silver. Still contemplating battery options...