Issue with house batteries

[bgosden]

Second issue we could use some help with. We are brand new to RV'ing and have a 2003 Winnebago Itasca Sunova.

We were noticing issues with the house batteries staying charged, so we replaced them with brand new ones as it had sat for awhile and we suspected they might be bad.

We took it out for the first time, and while driving for about 7 hours, we lost all power in the house and from our levels check looked like the house batteries were dead, leading us to believe the alternator on the engine is not charging the house batteries. With the generator running, we started to get some charge back on them but thought with that long of a trip the alternator would also be charging the house batteries. I feel like this may be a simple fix and be due to lack of knowledge on our part of how things work, but any insight as to what could be the issue would be appreciated.

[MrWizard]

A factory converter install
The converter is built into the load center that houses your circuit breakers and fuses

A stand alone inverter could be mounted anywhere between the transfer switch (switches power between generator and shore cord)
And the load center, normally installed not too far from the house batteries

Is there anything in the rv that needs 110vac that will work when the generator is off and the RV is not plugged into outside power
Example television, kitchen or bathroom outlet
Yes then you have an inverter some where
No then you do not, as you only have the converter behind the load center

Look for a hidden switch that is turned on
Perhaps you have holding tank heaters that are turned on, storage compartment lights that are on,
Defrost switch for the fridge doors, ??

The words inverter and converter are not interchangeable, they are different things that do the opposite of each other

[wolfe10]

bgosden wrote:


For the alternator- When we went on the trip, the person that sold us the new batteries had told us to move our trickle charger to the house batteries instead of the chassis. So we had batteries charging.. from themselves. I suspect this is why we lost all power when driving.

Sorry, the trickle charger has absolutely NOTHING to do with the alternator charging both battery banks when the engine is running.

You really need someone familiar with RV's to troubleshoot your charging system-- both from shore power/generator AND alternator.

[mchero]

wolfe10 wrote:
Duralast Marine and RV Deep cycle, 24MD-DL probably not a great choice in terms of either capacity or longevity.

I googled that model number and see it has 550
Cold Cranking Amps 😞

Also, My norcold 4 door has two 120VAC outlets on the backside. One off the panel and one off the inverter. The ice machine was plugged into the inverter side.

[MrWizard]

we should NOT be losing all battery power within a few days with the fridge on Auto and nothing else on
Wrong

Turn the fridge off, for testing your battery problem, unplug the 120v cord at the back of the fridge
The 12v controls draw very little power
But if it's running from the inverter, you are using about 30amps draw on the 12v
The electric heating elements in an RV fridge are around 340 watts of power, that's 3 amps on Shore power , but takes 30 amps 12v power into the inverter to make 3 amps at 120v
Plus conversion losses

[bgosden]

*I think* the alternator is, but the converter seems to be something that just keeps coming up, and I am not sure why I am having so much trouble finding it 🙂

For the alternator- When we went on the trip, the person that sold us the new batteries had told us to move our trickle charger to the house batteries instead of the chassis. So we had batteries charging.. from themselves. I suspect this is why we lost all power when driving.

When we got home and changed the trickle charger setup, someone else advised we test volts on the batteries which we did- 12 volts when engine was off, and then when we turned it on they went up to 13.6ish. This leads me to think the alternator is working as it should, but the trickle may have been the culprit on the drive.

Am I correct in thinking that with the batteries fully charged from shore power,then disconnecting, we should NOT be losing all battery power within a few days with the fridge on Auto and nothing else on, but of course things plugged in? Does this sound like an issue with the converter/inverter/charger most likely not slowly charging them?

Thank you all again.

[wolfe10]

Duralast Marine and RV Deep cycle, 24MD-DL probably not a great choice in terms of either capacity or longevity.

BUT, if they are being properly charged (engine alternator and/or from converter or inverter/charger when on shore power or generator, they are probably not the problem.

You need someone to help troubleshoot your charging systems. Sounds like neither your alternator nor your converter or inverter/charger are charging the batteries.

[mchero]

Your going to have to find that inverter/converter as well. The batteries are only half the story.

Of all the systems in these RV's I'd say the house batteries are the most abused. Hate to see people purchase new deep cycle 6v house batteries only to find them flat dead a few days later.
Soooooo bad to run deep cycle lead acid batteries flat dead!
I had a 93 Pace Arrow Diesel for 12 years before our current rig. One of the first projects was replacing the house batteries, 4 six volts from Sam's Club. Back then about 85/pop.
Replaced some of the battery cables and also replaced the "charger", the Pace had separate inverter and inverter. Purchased a Progressive Dynamics 60amp charger with charge wizard pendant. Got 10+ years out of those batteries. Over half those years I did'nt have the rig plugged in during out NH winters! When I winterized I'd fully charge the batteries and disconnect the neg. lead.
That converter or charger should hum. Perhaps if you make sure its absolutely quiet and listen for a hum where you think one inverter is.
It should be very close to the batteries. Dont want long cable run from house batteries to inverter/converter or charger.

[bgosden]

MrWizard,

I would think being plugged into the house for four days would fully charge them, but I am so new to this, maybe I am wrong.

There is an inverter/charger/converter somewhere, but I have yet to find it. The user manual says- The converter is located in the bottom of the galley, in a cupboard, or under a bed. I do not know exactly what I am looking for, but so far, cannot find it.

The fridge is set to Automatic right now, as we have been attempting to figure out a problem with that because it was fault coding. Could it just be that draining the batteries? How long can you run the fridge on just house batteries normally?

Have not checked the water heater yet, but will do.

Thank you!

[bgosden]

2003 Winnebago Itasca Sunova- New to us, second owners, our first RV.

We have not done any dry camping in it, or any camping at all for that matter. Trying to sort out the issues before we can do that, and have had it for about a month.

We thought we had solved the battery issue by replacing the batteries, but then decided to drive it to Colorado and about 4 hours into the drive we lost power in the motorhome, while the engine was running so that brought us back to something being wrong.

The new batteries are Duralast Marine and RV Deep cycle, 24MD-DL. There are two of them.

[wolfe10]

If you want us to comment on whether you have the correct batteries, you will need to tell us what batteries you have and how many?

Also, what RV and how much dry camping you do.

[MrWizard]

Assuming that the batteries did get fully charged
And you do have an inverter
You have something running on inverter and draining the batteries
Maybe the fridge set on automatic and switching over to 120v
Or maybe the water heater set on electric

[bgosden]

The batteries are brand new as of less than a month ago, as when we bought it we had the same issue and thought it would be the batteries as they were original from 2003 so replaced them.

Is it possible we bought the wrong batteries and that could be the issue? Knowing now that the tech that sold them to us told us to put the trickle charger on the house batteries instead of the chassis battery, I am wondering if perhaps he did not have the knowledge and sold us batteries that would not work for our setup, or is that even a thing?

[wolfe10]

bgosden wrote:
It appears something is draining the batteries, but I have no idea what or why they cannot stay charged even for a couple days?

Indeed, you could have EITHER bad batteries or significant phantom draw.

Start by fully charging the batteries. Then have them load tested.

Yes, if you have an ammeter you can search for any draw. But, I would only do that after proving the batteries good.

[bgosden]

Update here- Still have not located the charger/inverter/converter, but was doing some testing before continuing to try to find that.

We disconnected the trickle that was charged into the house batteries, and moved it back to the chassis, hoping that was the entire problem, but it appears not. Plugged into our house for three days and fully charged the house batteries, no issue there with charging- Disconnected it two days ago, and yesterday the battery showed 1/3 charge by end of day. This morning, battery is showing dead and have lost power to the microwave, but can still turn on the house lights. It appears something is draining the batteries, but I have no idea what or why they cannot stay charged even for a couple days?