Wire Nuts (factory) vs splice

[mleekamp]

We just picked up a new Class C (see sig). Out of the half doz TT's we used to have and now this C, the wiring for the tanks always seems half done from the factory. The small wires are connected with wire nuts vs. a sealed splice.

I've fixed my units in the past, but is it necessary? Do any of you fix the sometimes weird stretched wiring, wire nut connections that seem like a 15 year old in hurry did them?

[Lynnmor]

Ideal is a large manufacturer of wire nuts, their instructions are:

Installation Instructions
1.Turn off power before removing or installing connectors.
2.Strip connectors to the correct strip length per the chart
3.Straighten and align frayed strands.
4.Hold wires together with ends even. Lead stranded wires slightly ahead of solid wires.
5.Pre-twisting acceptable, but not required. For pre-twisting;
strip wires long, hold wires together with insulation even,
twist wire ends together, trim to recommended strip length.
6.Insert bundle into connector and twist clockwise until tight

[myredracer]

mike-s wrote:

myredracer wrote:
I have to disagree with your disagreement. Wire nuts, aka "marettes", are used in buildings all the time including critical installations like in hospitals.

Name where in a hospital, and subject to frequent vibration, they're properly used.

Where in a hospital is there frequent vibration in the building structure? All I've ever seen in any building construction in commercial to institutional (incl. hospitals) is standard marettes (and def. not residential grade) for branch circuits. Meets CSA, code and gov't requirements (where applicable) and engineers specify conductors to be pre-twisted.

[Dusty_R]

Not all wire nuts are created equal. I've had wires come out from wire nuts when tucking them the into junction, even though they had been tested by tugging them after the wire nut had been turned on, and they would not pull out from the joint.

[drsteve]

DrewE wrote:
...the worse that can happen is that your tank level meter fails to give an accurate indication...

It will do that even if the wire nuts remain in place...

[mike-s]

myredracer wrote:
I have to disagree with your disagreement. Wire nuts, aka "marettes", are used in buildings all the time including critical installations like in hospitals.

Name where in a hospital, and subject to frequent vibration, they're properly used.

[myredracer]

robatthelake wrote:
There is absolutely no way that wire Nuts should be used in any RV wiring! Those things are barely adequate in a stationary building! I found them used to connect the Furnace and Air conditioning in our Rig and hidden inside compartments that normally would never be opened for inspection!

I have to disagree with your disagreement. Wire nuts, aka "marettes", are used in buildings all the time including critical installations like in hospitals. The problem is that they are often not correctly used. The professional way to use them is to pre-twist the wires with linesman pliers, trim the end off as needed and then install the wire nut.

RV factories do terrible workmanship when it comes to wiring like the splice in the 1st photo. This was found in the 4x4 junction box in our A-frame. The wire nut was upside down and filled with water (as were a few others in the same box). I moved all the splices in the A-frame area into a watertight PVC box. Third pic is the mini-breaker in the A-frame and from the main + wire off the battery. The splice wasn't even close to being done right and the wire fell right out of the ring terminal when I touched it! The metal boxes RV factories typically use in A-frames are for use in indoor dry locations only.

Splicing stranded wires with a regular wire nut is not easy to get right and needs more care. I prefer to use "vibration resistant" wire nuts in that case for a better and more reliable connection for 120 volt splices, as in last pic. For 12VDC splices, there are a number of methods that work fine *IF* they are executed properly.

Splices for ALL 120 volt connections are required by code to be accessible and cannot be hidden behind coroplast or anything else.

Although there is the NEC that has a section specific to RVs, the problem is that they never get inspected and there is no gov't agency to complain to. I can't believe some of the electrical issues I've seen. :M

Bad workmanship - pls don't get me started, pffft...

[mike-s]

ScottG wrote:
I crawled around under our new TT and siliconed a bunch of splices for lights. Otherwise they would have filled with rain and coroded.
They should do things better.

Silicone RTV should never be used on an electrical connection, unless it's specifically labeled for such use. A lot of them produce acetic acid when curing, which can corrode the connections you're trying to protect.

[2manytoyz]

I spent a weekend helping a friend rewire his Airstream Land Yacht. All the tail light wiring had wire nuts. Only half the lights worked. I used a waterproof splice to fix all the connections. But the more we looked around his camper, the more we found.

Wire nuts should NOT be used on DC wiring on a moving vehicle. Sooner or later, they'll become an issue.

I chose to replace all the ones I can find on my rig, at my convenience, while at home, rather than on the side of the road, or some remote campsite.

Here are the terminals I use: https://www.amazon.com/Connectors-Waterproof-Electrical-Terminals-Automotive/dp/B075TYSD26/

And here's one of the crimpers I use: https://www.amazon.com/gp/product/B0069TRKJ0/

My other crimper is an Amphenol Model 59250. These cost over $1K new. I use these in the aerospace industry. I bought a couple of used ones on eBay for $100-$150. For the average person, these would be overkill.

You can be proactive, or reactive. You decide what's right for you.

[robatthelake]

There is absolutely no way that wire Nuts should be used in any RV wiring! Those things are barely adequate in a stationary building! I found them used to connect the Furnace and Air conditioning in our Rig and hidden inside compartments that normally would never be opened for inspection!
This was in a Newmar Dutch Star!

[DrewE]

My 20 year old class C has wire nuts for a bunch of the wiring in many places and I don't believe I've seen any evidence of one failing or having failed as yet. Coachmen did generally tape them to prevent unscrewing from vibration.

Particularly in this case, where the worse that can happen is that your tank level meter fails to give an accurate indication, I would leave well enough alone for now and maybe change things if a repair becomes necessary later.

[azrving]

Ralph Cramden wrote:

nayther wrote:

Ralph Cramden wrote:
Now if it had coroplast they could have hidden even more shoddy assembly from view, including Jacob Yoders half eaten ham sammich.

Been wondering that on my new one too. How much crappy work is hidden from view above that ****. First "enclosed" underbelly rig I've owned.

I had an Aerolite hybrid with the coroplast, had to drop it to weld a spin fitting on the water tank. I found more hardware inside there than aisle 11 at Home Depot, and a nice almost new pair of Klein dikes. Sort of a bonus. That coroplast adds nothing. Its a piece of cheap plastic marketing. All it adds is a headache when you need to access someting which at some point you will most likely.

I rigged out an older FW for my son and it had a sheet metal belly with plywood backer glued to it. I cut holes and made covers in several places so the valves, slide motor and a few other things could be reached. It was all crimped at the joints to form one piece under a 35 ft bunk fw. To remove the whole thing the springs had to be dropped. Insanity with absoluety no concern for repairs that are needed later.

[Ralph_Cramden]

nayther wrote:

Ralph Cramden wrote:
Now if it had coroplast they could have hidden even more shoddy assembly from view, including Jacob Yoders half eaten ham sammich.

Been wondering that on my new one too. How much crappy work is hidden from view above that ****. First "enclosed" underbelly rig I've owned.

I had an Aerolite hybrid with the coroplast, had to drop it to weld a spin fitting on the water tank. I found more hardware inside there than aisle 11 at Home Depot, and a nice almost new pair of Klein dikes. Sort of a bonus. That coroplast adds nothing. Its a piece of cheap plastic marketing. All it adds is a headache when you need to access someting which at some point you will most likely.

[Papa_Steve]

Mortimer Brewster wrote:

DutchmenSport wrote:
If everything is working, why mess with it?

It’s a preventative thing. For example, we had our dog fixed even though everything was working fine.

Did you splice his wire nuts?

[beemerphile1]

I am short of time to accomplish all the work I need to get done. I don't create extra work fixing things that aren't broke.