Battery problem

[Sue and Henry]

Leaving home this morning, we unplugged from the house and switched over to direct current as usual. It all looked good at that point. Our new battery reader was at 20.2

After a four hour drive to our campsite, before disconnecting from the car, we opened the casita door and found the the reader down to 11.3, the clicking sound from propane lighting attempts and the light on the refrigerator battery/electric/propane controls flashing along with the interior lights (flashing) when turned on.

We switched over to plug in power three hours ago and the battery reader is up to 13.77 now. All the clicking and flashing stopped as soon as we went to shore power.

Our next stop is a boondock spot and we were planning to go battery power for a few days. Yikes!

Anyone know what is going on?

[Raspy]

First, what do you mean by 20.2? Volts? Yikes.

Second, you weren't getting power from the TV to the trailer battery and it went dead while driving and trying to run your accessories. It also sounds like you may have a small battery that will not be adequate for "a few days".

It sounds like you need to figure out the TV power wire, be sure you have an adequate battery for your needs and manage your power use.

[Sue and Henry]

Hi Raspy,

You are right. I must be miss-remembering the starting reading. The battery reader is a very new toy for me and I'm not really understanding it yet.



I just switched back to battery again to see if it was still doing the flash and it is not - but it is now charged to 13.79 and according to the picture, that's in the green zone. 11.8 and lower is the red zone - so maybe I've messed up my relatively new battery - and all lights blink and the propane clicks when the battery is low.

[ninklink]

We have 2 interstate deep cycle batteries but they seem to go down too fast while boondocking recently. I left my wife and dog at Kilby Campsite on the Harrison River in BC while I had to work. Got a call that she was in the dark - no power. Even though we have a 40w solar panel it wasn't enough to top the batteries during full sunny days. The camp host helped her out with a noisy genset but I decided to buy the Yamaha 2400Inverter genset which I brought out and it got the batteries up and powered the Bigfoot but the batteries did not hold charge until morning. Either I have a mystery draw like maybe the radio or the 5 year old batteries are finished or both. I read the other post about a battery switch to isolate batteries. I' thinking of buying a couple new batteries and switching out the radio so that when its off no lights are visible. Which 12 volt Deep cycle batteries would anyone reading recommend? Also which Bluetooth radio with USB charger would anyone recommend? We're in BC but I have a shipping depot in Sumas WA.

[Raspy]

Sue,

If you have a smart charger, it will bring the battery up to about 14.1 volts and then go into float mode which will settle down to about 13.2 volts. This is normal and good. If you disconnect the battery for a period of time, several hours or overnight, it will then read about 12.6 to 12.7 volts.

If you have an older design converter, it will have a constant voltage output of about 13.2 to 13.5 volts. These are not very good for batteries and might be the reason you have a low apparent battery capacity. Don't know what battery you have or your continuous amp draw is, so I'm only guessing.

If your battery is older and has been allowed to get repeatedly discharged to near dead or sit dead for a period, it is probably not useable anymore. If you are not sure, you could take it to an auto parts store and have them do a load test on it. In normal use the battery should not be pulled down to a reading of less than about 12.2 volts. That means it would read 12.2 on your volt meter with no other load on it.

[Joe Romas]

Sue.

Were you running the refrigerator on DC (battery)?

If so that explains all your problems.

Most TV's are not wired well enough to charge your trailer battery and run the refrigerator at the same time and your trailer battery will quickly be run down.
The refrigerator on my 1999 17' Casita draws 14 amps

[padlin00]

Ninklink, I've always had good luck with Interstates. Other top brands are Trojan, and Lifeline but they are harder to find. A Pair of 6 volt batteries hold more then a pair of 12 volt, but cost more. If you go 6 volt you need to wire them differently.

If you don't have one, get a digital voltage meter of some sort, they have them that plug into a lighter socket, and look up how to tell your battery charge level from the readout. Try and avoid going below 50% charged.

Sue, you might want to forget about heading to a boondocking site today if you're still having battery issues. Electrical problem troubleshooting can be pretty involved and time consuming to find, especially via the internet.

For a start, check your connections to the batteries, make sure they are not loose. Check the water level of the batteries. Charge then batteries for 24 hours, disconnect the charger or disconnect from city power if you are using the converter. Turn off all loads, let the trailer sit for a few hours and check the voltage level at the battery posts. Should be about 12.6

[C&G in FL]

Don't want to open up the can of worms debate again, but after going through the discharged battery problems, several years ago I took a deep breath and started running the refrigerator on propane (as a large number of people do) and have had no problems with batteries since then. Yes, I was reluctant to do so and worried a bit at first, but now I am comfortable with running on propane. You've got to do what makes you at ease, but running a refrigerator on 12v (unless you have modified the charging system) will almost always have a detrimental effect on the battery/batteries.

[Mike Magee]

Optima batteries are well thought of also.

[Sue and Henry]

I'm going to try running the refrigerator on propane and see if that cures the problem. I rarely travel more than four or five hours a day so I'll stock up on freezer ice packets for the traveling time and go propane when I'm parked.

Traveling with the the fridge off, I was surprised that the battery reader dropped from 13.82 when I started today to 13.3 when we arrived 3 and 1/2 hours later. Nothing was running on the casita battery and I thought it should be charging from the car a bit.

Oh, so much to learn! Than you for the help and ideas you guys. You are the best.

[Sue and Henry]

Bob,
I have given up on the boondock option this time around. It's dropping to 32 tonight and that's chilly for me - especially if I am having electrical challenges. Thanks for the "how to check it" advice. It's unplugged from city power now and I'll be checking the little guy in a couple of hours. Thank you!

[Glenn Baglo]

After unplugging the trailer/battery from shore power, you need to wait an hour or two for the 'surface charge' to dissipate. Then you will get an accurate reading.

[Raspy]

Just unplugging the trailer and then checking the voltage later, shows the affect of any unknown loads and the battery integrity. If the battery is bad, it needs to be checked independently by getting fully charged, the battery cables disconnected, and then checked after resting. That test can be done and then another test with the cables connected. The difference is caused by loads.

The suggestion that the fridge was running on 12 volts while driving is a good one and could explain the problem. Running the fridge on 12 volts while towing does not always work out and I never do it with mine. A resistance heating load on a battery is not a good idea unless and only if there is a proven charging amperage strong enough to handle it. Running the fridge on propane is much better and assures the battery will be fully charged when you stop for the night.

[gordon2]

Originally Posted by Sue and Henry

...

Oh, so much to learn! ....

start here:
The 12volt Side of Life (Part 1)

Judging battery state of charge by voltage alone is a crude and often inaccurate method. The suggestions above to disconnect the battery and let it stabilize and/or dissipate the surface charge before reading voltage are correct and will increase the accuracy of the reading. A more accurate method is using a hydrometer and that should be done if you suspect the battery has been damaged or over-discharged.

If you install a shunt and meter that reads the actual current going in to or out of the battery then you will know what the load is. This includes when hooked up to the tug, even if running the fridge. If you then find that you have a negative current flow from the camper's battery while the tug is connected, running and the fridge is on, then you can figure out how fast that would kill your battery (defined as over 50% discharge).

[Joe Romas]

Sue

The drop from 13.8 to 13.3 you saw is normal.
As Glenn and Gordon said you were seeing the "surface charge" bleeding off.
This can take as long as overnight with no load or less with a load applied.
A fully charged battery minus the surface charge is somewhere around 12.6 that you were way above. Go to Gordon's link, print out the chart and tape it to the cabinet by your meter.

One brand of trailer, don't recall what one, only has a 2 way refrigerator, AC and Propane, that totally eliminates the problem

Joe

[steve dunham]

Originally Posted by Joe Romas

Sue

The drop from 13.8 to 13.3 you saw is normal.
As Glenn and Gordon said you were seeing the "surface charge" bleeding off.
This can take as long as overnight with no load or less with a load applied.
A fully charged battery minus the surface charge is somewhere around 12.6 that you were way above. Go to Gordon's link, print out the chart and tape it to the cabinet by your meter.

One brand of trailer, don't recall what one, only has a 2 way refrigerator, AC and Propane, that totally eliminates the problem

Joe

I have often wondered why the refrigerator has a 12 VDC mode .
It seems after reading these forums it creates a ton of problems and solves none
When traveling, if we're only going a short distance we leave the refrigerator off , when we are going to drive all day we run the refrigerator on propane. So far our system has worked great.

People go through all these elaborate, complicated, expensive steps so they can run their refrigerator on 12 VDC but why , for what gain ?
(Dual Batteries , rooftop solar , running a #2 charge wire , remote bluetooth battery monitors, quad batteries , a gazillion watts of solar . AGM batteries etc etc etc.

A friend of ours just bought an expensive 5th wheel trailer and his refrigerator is only a 2 way. 120V AC / propane.

[Snoopwagon]

I have A casita also I use the 12 v dc to travel on fridge but turn it down to 2 seems to do ok but you should have atleast a 120 ah batt/ 😊

[Snoopwagon]

13.82 it was bulk chargeing 13.2or 3 is going to float voltage seems ok as long as your not below float

[gordon2]

Originally Posted by steve dunham

I have often wondered why the refrigerator has a 12 VDC mode ...

My understanding is that the 12 volt mode is designed and intended only to maintain the temp of a pre-chilled fridge while in transit and while getting power from the tow vehicle, and while not being opened.

Originally Posted by Joe Romas

..
One brand of trailer, don't recall what one, only has a 2 way refrigerator, AC and Propane, that totally eliminates the problem
..

Well any brand of trailer could have one way, two way or three way.. my model of Scamp comes with a smaller 3 way or a larger two way (no 12 volts). Those are both options since an ice box is standard equipment which of course also totally eliminates the problem.

[steve dunham]

Originally Posted by gordon2

My understanding is that the 12 volt mode is designed and intended only to maintain the temp of a pre-chilled fridge while in transit and while getting power from the tow vehicle, and while not being opened.



Well any brand of trailer could have one way, two way or three way.. my model of Scamp comes with a smaller 3 way or a larger two way (no 12 volts). Those are both options since an ice box is standard equipment which of course also totally eliminates the problem.

I agree that the 12 VDC system is designed to maintain temperature while traveling.
My point was that often running the refrigerator on 12 VDC
while traveling slowly drains the trailer battery . After a long day of driving you can end up arriving at your campsite with a depleted battery. ( Our experience)
Why take that route when you can run the refrigerator on propane and arrive at your destination with a cold refrigerator and a charged battery.
If the average tow vehicle could supply enough power to run the refrigerator on DC and charge the trailer then it might make some sense but that's not usually the case.