Rv wiring help please!

Oct 31, 2011
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East KS
#1
Grandparents took the 5thwheel out and I have my son out with then this weekend camping.
Internet sucks so Google isn't helping.
So next best thing ask you guys.

Trailer is plugged into the 110 volt at the camp site. Plugs work inside. Microwave works. The 110 only lights work.
Every thing that can run off of 12 volt battery is still trying to run off of the battery. Can't find a switch.
Fridge a/c and some of the lights and waterpump are all trying to run off of 12v / gas.

Any ideas? ?
 

buffalowinter

Rick Jones MAJ, SF (Ret)
Mar 17, 2014
758
844
93
Llano, TX
#2
The switches in my trailer are all above the fridge on a panel that has a cover on it. It's a "hidden" drop down panel with a selector for 110/gas. Should be an ac/ gas switch somewhere. Check by the fuse box or by the battery to switch. No way fridge or A/C are running off the battery...look for a switch by the gas tank to switch to 110 or on the appliance myself. If the amp rating on the 110 outlet isn't sufficient, i.e. less than 30 amps, A/C and Fridge won't work.
 
#5
Some things never switch over to 120 VAC. Lights stay 12 volt all the time. Your fridge should have a button above the door that says, LP/ Auto. Press the button, and it will switch to 120 VAC all the time, or go to 12 volt (for the internal mother board only) and LP (for the heater-tube, that evaporates the ammonia. Regardless it will still draw from 12 volt, since that is how the mother board is powered. The 120 VAC simply heats the element. (Seems counter-intuitive to use heat to make cold, but that is how it works)
The water pump is ALWAYS 12 volt. No matter what you are plugged into. If you are hooked up to city water, then simply turn off the water pump, at the pump switch. City pressure will be enough.
Your water heater is able to run on propane and sometimes on 120 VAC, which is a little black rocker switch on the front of the water heater itself. Open the gridded cover outside, and look under the burner. If it has the little rocker switch, AND the tank is already full, then turn it on, and it will keep the water hot around the clock (ONLY if tank full, and coach plugged into 120VAC, also known as "shore power" )
If you leave it on propane, it will come on every once in a while. I save propane when boondocking, by leaving the water heater turned off until I need it for a shower. It will stay hot all day without running.
I have full timed in an RV for many years, on and off, and owned RVs for the last 40 years. There are a few tricks that once learned will tide you over on any RV you use.
Buffalowinter brings up an important issue: Many power supplies in RV parks have inadequate wiring, and or incorrectly wired power. I have a "Progressive EMS" which plugs into the post and into the power line going to the trailer. It automatically diagnoses the condition of the post, and if OK, show that on the read out, then allows electricity to flow. If there is an error (insufficient voltage, open ground, excess voltage, or other problem) it will show that, and then not allow power to flow. If you have a MultiMeter, then always check the post before plugging in.
Before plugging in, make sure the breakers on the post are thrown off, after testing and before plugging in. Inspect the plug holes for signs of arcing, and before you close the breakers, push in and pull out the plug a couple of times to make sure the fit is tight. A loose fit can lead to arcing, and can cause overheating or a fire, or other damage.
good luck.
 
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Oct 31, 2011
630
130
43
31
East KS
#6
Thanks guys.
I've played with the gas/power switch.
The ac won't run plugged into 110 the fan for it will run when I put jumpers on the battery.
Battery is not charging even with everything that runs off of 12 off.
110 volt only works.
I'm starting to think it's the inverter.
 

Foul Mike

Gunny Sergeant
Apr 18, 2001
1,491
548
113
Eastern Colorado
#7
I am betting the inverter is shithouse.
When I was doing it I carried a spare inverter for when times like this showed their ugly head.
That is where I would start checking. Don't miss my trailer at all. Too many people and hard to find a space to park in.
 
Likes: Slash0311
Oct 31, 2011
630
130
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31
East KS
#9
Since I have my son and my mom has a heart problem so she has to have the ac.
We just went home.
It's either the inverter or the power hook up at the campsite.
Thanks guys for the help I learned a few new things.
 
Nov 10, 2010
3,341
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UT
#10
A/C will only work with shore/generator power (110 volts/ 60 Hz) if you get home and it works off your house then campsite power was dicked.

PS. Sorry to hear about your get away being ruined. I have had many a camping trip like that.
 
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#12
Last couple of thoughts: Before changing a high dollar item like the Inverter, Check the battery (which isn't taking a charge: If it is only one battery and more than a couple of years old, it may be dead, as in unrecoverable. Check fluid level, and volts under a load, as well as using a hygrometer on the fluid. Should all test hot. Again, if only one battery, you really need two, so you have at least 200 amp/hours. Not a marine battery. I prefer 210 amp/hour 6 volt golf cart batteries hooked up to make 12 volts. Costco. 89 bucks each.
Next, use your multi-tester to check the post. It might be a screwed up instalation. and that is so common, I have lost count of how many times I have had to run on my generator and/or solar panels due to having to wait for another space because the maintanence guy wouldn't or couldn't fix the post and it's incorrect wiring.
The Roof Air Conditioner Is notorious for having a high draw on start up. Lots of You-tube stuff about putting in "Soft Start" modules so they can be run on 3000-4000 watt generators or 15 or 20 amp house plug. You have at least 30 amps, and probably 50 amps for a 5th wheel. One leg for each air Conditioner. I have a 5,000 watt Onan generator on board and it runs BOTH A/c's and the microwave and my tv all at the same time, with not even a noticeable draw-down (where the engine bears down) and that's with the elec water heater and fridge going. You should be able to do the same.
Finally, if thisis YOUR RV, get a Progressive EMS. spend 300 +/- bucks and save thousands in damaged electronics.
Checking your Inverter: You probably have a monitor, but may have to check function with a technician. do the battery, and post checks yourself. go from most inexpensive part to most expensive parts before you jump right into replacing the inverter.
The all-time master of RV electric is Brian Boone, on Facebook. He has several RV electrical and Solar power pages, with lots of files available for all that.
Best wishes, and good luck.
 
Likes: tea&jam
Nov 25, 2007
2,156
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Lithia, FL
#14
Battery problems are related to bad connections many times.
Example;
I live very near the coast.
My skiff had an issue with the two Oddesy 1500 batteries not wanting to charge. Since it was late, I unplugged it and waited until morning.
Now salt water is notorious for causing electrical issues, so my first check was to make sure the connections were not loose.

Not the problem.

Next check was to disconnect each wire and clean, lube with dielectric grease and reinstall.
Once done, everything worked like a champ.

If I had not done the simple things first I would have never found the actual problem, and I would have ended up replacing $450 in batteries or a $350 dual bank charger.
 
Likes: hankpac
Oct 31, 2011
630
130
43
31
East KS
#15
I know the ac is 110 but I still don't get why the only time the fan for it would come on was when I had the jumpers from the truck on the battery.
Plugged in the jack and slide would not work both 12v
The only things that would not work was the 12v.
My thinking is the battery shouldn't effect the 12v system if it's plugged in to 110 if the inverter is working.
 

Geno C.

Dirty Carnie
Oct 24, 2007
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Wautoma, WI
#17
Thermostat is most likely wired to the 12v circuit. That's why when you gave it 12v with the jumpers it would work. I've seen quite a few trailers wired that way.
First thing is the check the battery.

Next check that the inverter is getting power IN.

Next check that the inverter connections at the fuse panel are tightly connected.

The inverter outlet connections should be 12v or higher. The connections at the fuse panel should be the same.

If all that checks out, pm me your number and I can walk you through anything else I can think of
 

Geno C.

Dirty Carnie
Oct 24, 2007
2,506
2,830
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34
Wautoma, WI
#18
I know the ac is 110 but I still don't get why the only time the fan for it would come on was when I had the jumpers from the truck on the battery.
Plugged in the jack and slide would not work both 12v
The only things that would not work was the 12v.
My thinking is the battery shouldn't effect the 12v system if it's plugged in to 110 if the inverter is working.
If the battery has a dead or shorted the inverter won't power the system
 
Likes: 2ndamendfan
Nov 25, 2007
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Lithia, FL
#30
Get a wallmart battery, I grantee it will go out before warranty goes out.
Bought some for my boat had 8-9 years worth of free replacements.
Been there, done that way too many times. Those cheap assed batteries always fail at the worst possible time.
I have Oddessy 1500 batteries for my trolling motor. The only reason the main battery isn't the same brand is because it failed and wouldn't even jump start on a weekday fishing trip. Rough week and I needed to be on the water.
Bought a replacement at advance auto. When it fails, and it will, I'll buy another Oddessy.
 
Likes: barneybdb

Snuby642

Sergeant of the Hide
Feb 11, 2017
814
381
63
#31
Oddessy bateries are not sold at every podunk crap hole in the US in case it needs replaced.
I can probably buy 3 wallys for the price of one oddessy.
I used to fish 3 days a week minumum, rain or shine tournaments on the line.
Just why dont you tell me about a damn battery.

Expendable shit, throw extras in the truck and troll on.
 
Nov 25, 2007
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Lithia, FL
#32
I don't do tournaments, nor do I want to carry spare batteries around.
What I do want is total reliability and long life with really long run times. I have that with these batteries.
I understand being able to buy three Wally world batteries for the price of one, but I can't afford cheap shit.
Fortunately, with all the different brands out there, we have choices to meet our needs and budgets.
 
Likes: barneybdb

Snuby642

Sergeant of the Hide
Feb 11, 2017
814
381
63
#33
Seems like if given enough abuse all batteries take a dump eventually.
Bad roads, jumping waves, hitting stumps, heat and cold can kill even the best of batteries.
Then while fishing offshore you dont want to know the stuff we broke.

Many a day I loaned or sold my cheap ass spares to competitors.
I didn't have a battery sponsor, that would have been nice.
In general the "good batteries " last longer have more power, I will give you that.
But are not as expedient to replace, they all die.
 
Nov 25, 2007
2,156
1,680
113
Lithia, FL
#34
I run a pair (24v) in the front hatch of my skiff.
The hull on my Hewes is flat bottomed with a modified V.
With the hull design, batteries take a huge beating whenever I'm running in more than a 1' chop.
Running in the mangroves or up/down river doesn't pose a problem, but crossing the bay or running out to fish a wreck isn't a pleasant experience on most days.
Lesser batteries would have died many deaths by now.


With your experience running off shore, I'm sure you have taken a few beatings due to wind and wave action.
 
Nov 25, 2007
2,156
1,680
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Lithia, FL
#35
Funny thing about cheaper batteries.
My Cadillac CTS needed a battery so I bought the gold series from Advance Auto. It came with a 3yr warranty.

At 2yrs, 11 months, it died.

They replaced it, no questions asked. Just under 3yrs later, yep, dead again, so another free battery. Two days before I got rid of it the battery was dead and they did another swap.
I got my $160. Worth out of it.

My wife's van is on her second replacement and it will probably die this fall.

For cars and trucks with low vibration applications, I'm all in buying lower priced units.
The funny thing is my diesel truck batteries are 4yrs old.
No warranty left on them.:(:(
 
Likes: barneybdb

Snuby642

Sergeant of the Hide
Feb 11, 2017
814
381
63
#36
Maybe a premium battery would be a good idea in an rv, I dont guess many people
Off road them, or jump hills with them.
My son bought some expensive batteries for his k5 for off roading.
They lasted longer but still broke at places no where near a dealer.
Had to get "wally class" replacement anyway.

I just got so used to breaking batteries, I opted for convenient replacement of mid grade "wally" stuff. They are certianly not the longest running.
 

Geno C.

Dirty Carnie
Oct 24, 2007
2,506
2,830
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Wautoma, WI
#37
Batteries are very unpredictable in the last 10 years. Used to be the high dollar ones would for sure last longer. I wouldn't bet money on it now. I have cheap batteries that have 15 years in them and going strong and I have expensive ones that haven't hardly made a season.

Our batteries in general see a lot of starting compared to running and sit for 6 months with no charging. It's actually a pretty rough life for a battery. Most of the stuff I buy for my personal stuff is the higher end interstate because I have a friend that's a dealer and get decent pricing. Company stuff gets whatever O'riellys has available. They're a good balance of price/longevity/ and availability.