Need help with electrical issue

[Landscapephoto]

Hi every one. I need help it seems like my batteries run down to fast. The last time I took my trailer out I had it plugged into the house for over 24 hours then drove 4 hours to the campsite. At about 7 that night I went in and turned on the furnace for about 15 min to warm up the the camper. Then turned it completely off. We went to bed at about 10 and battery indicator already showed 1/3. By 10:30 the alarm on the co/propane monitor was showing low voltage. In order to sleep that night I had to disconnect that alarm. The next day I ran my generator to put some charge on the batteries. By ten that night it was already back down to showing empty and then 1/3. When I got back from the trip I took the batteries out to be tested. They tested good at the auto store. But were discharged to about 27% which I know is not good for them. They recharged them. And they have been holding the charge. I took the trailer to the dealer and they could find nothing wrong with the trailer or my tow vehicle. They kept my camper over night. Still could not find anything wrong. The only thing they did not do is level the camper and turn on the fridge. I have been reading the forms and have seen where the domestic fridge can draw down batteries. For batteries I have 2 12 volts. I don't think I should run out of power in less then 8 hours with conservative use of all electrical systems. Has anyone had similar issues and found a problem.

[Cypressloser]

I think your batteries are fine, you may just not have true deep cycle batteries, aka marine batteries, which can be drained below 80%. You may want to try and get this information off of your batteries and post it here. Also, for a generator to charge your batteries to 100% it would take a full day, that's what battery chargers are for. Having said that, a slow charge at 10 or 20 Amp is preferable over a fast charge, let's say 60 Amp. Battery technology is a science.

[landsail]

RV refrigerators should always be run on propane when dry camping. Better efficiency and minimal use of propane.
Charging from the tow vehicle should charge the batteries but it depends on the wire size and vehicle connection of that conductor in the 7 pin trailer socket and trailer cord. Sounds like your trailer batteries are not deep cycle. Outside portable solar modules can really help recharging while dry camping , such as Zamp Solar units that come in different sizes, have an onboard charge controller, and padded carry bag. They also offer roof mounted modules that have a good weatherproof entrance housing. Mark

[Landscapephoto]

I have 2 12 volt rv marine batteries group 24. Also the fridge was in auto. From reading the manual it says it should switch to propane when it does not detect a 110 volts ac.

[camaraderie]

Originally Posted by Landscapephoto

I have 2 12 volt rv marine batteries group 24. Also the fridge was in auto. From reading the manual it says it should switch to propane when it does not detect a 110 volts ac.

You have a pair of 70amp hour Group24 DUALPURPOSE batteries. This lets you use 70 amp hours before your batteries are at 50% and need recharging...if new and undamaged. Yours obviously have less.
FORGET voltage readings in use...they tell you nothing about battery state of charge...ditto the little red lights.
It is also not clear to me that you understand the charging process.
1. Rolling down the road with the RV connected to the TV does not charge the batteries...at best it maintains them.
2. Once the batteries are at 50% then it will take at LEAST 4-6 hours on a generator or plugged into electric with your converter/charger before they are fully charged again.

If you are going to be boondocking...you're gonna need more and bigger batteries if you're typical...true deep cycle ones.
The other thing you need to do is figure out how much electric you use when boondocking OR merely sitting there without being plugged in.
I strongly recommend getting a $150 true battery monitor now...before you buy more batteries and installing it so you know how much you use daily and where all those amps are going! If you can't afford the real monitor at least get a clamp ac/dc amp meter ($50) and clamp it on your positive battery wire when nothing is running.
This will show you your parasitic loads and if anything is amiss and draining your batteries.
Next turn things on that you normally use...like the fridge, overhead lights, etc. and take readings so you know how much they draw. Then...in use you can tell how long you can use those things without killing your batteries.
Don't know what kind of charger you have but it should be a 3 or 4 stage with the capability of 25% of your battery amp hours....right now that would be 35amps ...but if you upsize your battery banks...you'll want a bigger one. It is absolutely NOT true that slow is better than fast...you want as much as the battery can take in bulk mode which is 25% of Capacity in wet cells. Then...after you are 80% full...that will taper gradually down during the absorbtion phase and then go down to just a few maintenance amps...that's the 3 mode charger. Helpful to have a 4 mode charged with an Equalization phase to help prevent battery sulphation over time.
Hope this helps.
Hope this helps.

[UT_Grandpa]

We have a new Rockwood Mini Lite 2509S and the battery rack in the tongue had no room for Group 27 batteries, so we have a pair of Group 24 batteries.

The big draws in new trailers with LED lights are the furnace and water pump. If you have incandescent lights then leaving a couple lights on can take a quarter of your storage in a few hours.

I suppose if you have a bad connection or two in the distribution then the battery gauge might look worse than it is. Take the readings at the actual battery terminals. A bad connection at the battery, the junction box, the power distribution panel can give a low voltage indication. It really doesn't take much to do this.

Good luck. Also, I change batteries every 5 years whether they indicate bad or not. 12 Volt cells go bad almost overnight with little warning.

[Bama Rambler]

Something else to check. You didn't accidentally have the tank heaters on did you?

Also, you don't have a 3-way fridge do you?

[bikendan]

Originally Posted by Bama Rambler

Also, you don't have a 3-way fridge do you?

The OP has a Flagstaff Micro Lite, so it should be a 2-way fridge.

[pmsherman]

If your Dometic fridge has a door heater strip, then the fridge will draw over 1AH/hour for the heater strip. The electronics board in the fridge also draws a little bit of power. Other devices in your rig also draw power, often called parasitic loads because they draw power even when the devices are turned off.

When I boondock, I go the fridge control board and unplug the light/heater wire from the board. This eliminates the power drain for the heater strip. An alternative is to remove the fridge light to get to the wiring behind it and add a switch next to the light to control power to the heater strip.

My house batteries needed replacing this year so I replaced the two 12V marine (hybrid) ones with two 6V golf cart deep cycle batteries. I figure that I increased the capacity of my battery bank by at least 30% with this change. This increase does not include any additional capacity available by discharging the new batteries below 50%, something that golf cart batteries are better able to handle than the usual hybrid batteries. My house batteries are also located in a location where it's almost impossible to check the water level in them. I replaced the caps on the batteries with ones that have visible float indicators and allow remote refilling of water when necessary.

Phil