dual batteries drain quickly

This may sound absurd, but probably has been done in an RV somewhere sometime:

Do you have a battery charger or converter trying to the charge the RV batteries that somehow got hooked up in such a way that the battery charger is powered by an inverter that is powered by the batteries?

shane102.sc wrote:
I cant find anything that is wrong. Any ideas????

Buy a DC clamp meter like this one. With everything turn off inside the RV, place the clamp around the positive battery connection. Unplug each fuse one at a time until and watch for the current to drop to zero.

That is where your power is going.

MEXICOWANDERER wrote:
Searching while blindfolded is definitely "not the hot setup".

Amen, brother !

Searching while blindfolded is definitely "not the hot setup".

Do you have a gauge or meter to tell you the drain in amperes?

If you do anything in an attempt to fix the problem do you have a way to know other than waiting to see if the batteries drain again?

One comment:
I have not far from me a 12 volt battery.. 25 amp hour. I have two more even smaller.

I have one pair of GC-2 230 Amp Hour

I have several in the 100 amp hour range give or take 5-10

What size are your 12 volt batteries?

shane102.sc wrote:
Well, I have a multi meter and cant find any draws on the battery as of yet. obviously some thing is draining battery. But how do you check if the inverter/converter is draining the battery?

At least two people have suggested that your batteries are not being CHARGED anywhere near enough.

And now I make 3.

It is not "obvious" that something is draining the battery.
That is only one possibility.
There are several.

For instance, new batteries often come 50% charged or less.....and the alternator in the chassis or tow vehicle often doesn't really provide much charge when going down the road (sometimes none). New batteries should ALWAYS be manually charged before installing.

And what are you seeing that makes you think that the batteries are DEAD ??

And just for curiosity, are they connected is series (6 V) or parallel (12 V) ?

Well, I have a multi meter and cant find any draws on the battery as of yet. obviously some thing is draining battery. But how do you check if the inverter/converter is draining the battery?

I would bet you are not getting charged properly, assuming the batteries are OK.

Do a few voltage checks to see what might be.

Check the unit batteries with nothing connected:
Check the unit batteries with the engine running:
Check the unit batteries with the unit plugged in to shore power:
Check the converter output right on the converter itself to see what the converter is putting out:
Check the vehicle battery when off:
Check the vehicle battery when running engine:

Most likely, there is a very loose wire somewhere, and while you think the unit should be fully charged, you have a loose connection and the charge voltage is just causing a loose connection to heat up.

In my case, everything was like you said, but I found the negative wire at the converter negative terminal to the battery was so loose it was barely connected. It had heated up and melted a bit of insulation, would not charge the batteries and worked fine with a couple of turns on the screw head.

Google battery parasitic battery draw ... should provide the basics for diagnosing. Yours sounds like something major ... the one time I had an issue it was the electric step motor which did not shut off. Providing some basic info about your rig - model, age etc might help.

something else IS ON
you just have to find it

possibilities
whole house inverter is on..fridge is set to auto instead of LP, get power from inverter and drains batteries
same for water heater on electric

short circuit connection in battery control center

individual components, converter and inverter
both on, converter trying to charge batteries, using inverter power from batteries equal constant drain loop

batteries NOT getting charged, you only think they are getting charged while driving

buy a digital multi-meter, learn too how to use it, keep it in the RV
must have for all 'modern' RVs