changing old 120v wiring in 54 year old trailer

OK see you there thanks

mark b. wrote:
To all interested, I thank you for your help and suggestions on this rewiring project. I do now have it complete with a 120v side and a 12v side--all up and functioning well.

Next step: figuring out my propane floor heater and oven/stove. Should I start a new forum for that??

Yes, a new post will get more relevant answers than changing subjects on this old thread.

Good to hear the wiring part is done and working!

To all interested, I thank you for your help and suggestions on this rewiring project. I do now have it complete with a 120v side and a 12v side--all up and functioning well.

Next step: figuring out my propane floor heater and oven/stove. Should I start a new forum for that??

OK, great insights....I think I can use the 14 GA I am using for the rest of the electric in the trailer...Thanks!!

I have never heard of 6-8 gauge wiring for an RV water pump. I have not heard of everything by a long shot, granted, so they may exist, but are not typical. My water pump circuit has a 15A fuse and I think 14 gauge wire.

mark b. wrote:
That's awesome...it had seemed from my reading that even 6-8 gauge wire was needed for a water pump..but not sooo?

IIRC, there is a single, larger wire on a separate circuit leading out of the converter for the water pump. It could be AWG 10 or AWG 12. A larger wire isn't needed in my case since I have a pressure tank and the "water pump" is a small compressor. I'd bet it doesn't draw over 5 A. You could check specifications on supply pumps and see how large a wire is needed.

The Shur-flo pump for a spray tank on my lawn tractor is connected with 14 AWG. Modern water supply pumps for RV's are very similar but checking specs is the best practice.

That's awesome...it had seemed from my reading that even 6-8 gauge wire was needed for a water pump..but not sooo?

I rewired my '71 Starcraft, both 120 VAC and 12V DC. I used a 75 amp load center I found on sale at Home Depot for the 120V and my old PD converter had fused break-outs for 12V. Since I now have solar charging and am always inverting 12V, I have a pretty sophisticated distribution panel with connections to two battery banks. The distro panel has (3) master disconnect switches to separate service to 12V devices and choice of battery bank. I used stranded 14 awg for all 12V power. All my lights are LED and there are a few power ports around the bunks, furnace, etc. I did run a discrete 12V (-) phase wire to all 12V devices. 12V troubleshooting can be difficult enough without worrying about loss of ground continuity. The separate (-) phase wire eliminates that.
Good luck on your electrical work!

Excellent pointers thanks Drew! Should a water pump have a dedicated line to battery? What gauge wire would you use for lighting circuits vs water pump?

The trailer frame certainly can be the 12V negative return, as for a car. It's also reasonable to run all the returns to the 12V panel (or some other convenient place) and thence back to the battery. In any case, the 12V negative should be bonded to the trailer frame, even if it's not the main return path.

Typical 12V wiring would be a circuit breaker or fuse close to the battery positive connection (within 18" is the standard, I think), then a relatively heavy connection to the 12V distribution panel via a disconnect switch. Most often the converter is also connected at the distribution panel, but it's okay and not uncommon to connect it elsewhere if that seems more convenient. From the 12V distribution panel, fuses protect the individual circuits.

There are a few things that have dedicated connections to the battery or to a buss bar or similar in that vicinity. Any unusually high draw device, such as a generator starter or sizable inverter, would not go through the distribution panel. The breakaway brake system for the trailer should also be wired directly so it can't be accidentally disabled.