Full Chassis Batteries until unplugged

[Domtomac]

A 12v battery has 6 "cells". Each cell generates approximately 2.1v when fully charged. You're battery voltage is rapidly dropping to 10.5 volts because one of the cells is dead.

[BaldDaddy]

So I was finally able to purchase the 4 Lifeline L16T batteries from a place down in Miami. Will be picking them up next Friday. Lifeline is having supply production issues and all of the other places I contacted were sold out, saying they don’t anticipate any new stock for 4-6 weeks. FYI.

Two questions: I need to remove the old batteries to swap out for the new ones to avoid having to pay core charges. (Got the batteries for $608 each). Once I remove the old batteries, can I put the coach back on shore power to keep the systems running (A/C, refer, 12v, etc.)? Second, after cutting shore power, turning off inverters via the basement dials, and cutting 12V via the salesman switch, are there any other tips/tricks to removing/replacing these batteries without getting “bitten”. I am not a fan of getting shocked, nor want anything to damage the coach systems. My plan is to follow Larry’s recommendation regarding mapping out and identifying the myriad of cables, working my way front to back to remove, and vice versa to replace.

Thanks!

[LWBAZ]

Eric, I’ll take a shot at answering your questions, but you may want to get more than one opinion.

Regarding activating shore power with no house batteries in place, I wouldn’t do that. You might get away with it if you turned off the breakers for both inverters, but even if that works you won’t have 12 volt DC power, hence no lights and no water pump. And you won’t have 120 volt AC power to anything that is powered by the inverter, meaning your refrigerator isn’t going to run. You might be able to run the AC units, but with no 12 volt power you probably won’t have a live VegaTouch panel, hence to way to adjust the set points.

Rather than even try it, I’d be inclined to pay the core charges when you pick up the new batteries, assuming the selling dealer will agree to refund the core charge money when you bring the old batteries to him within X days. That way you can do the removal of the old batteries, followed immediately by the installation of the new batteries.

For what it may be worth, there is a potential “work-around” that I’ve successfully employed a couple of times in years past. I usually have one or two (or more) slightly/lightly used 12 volt batteries in my shop/RV garage. For example, when our 2018 Cornerstone was fairly new, I replaced the original pair of engine starting batteries with higher-rated NorthStar batteries. I still have the original batteries, with each one connected to a CTEK charger to keep them charged up.

In a situation like yours, I have removed old house batteries, put a 12 volt battery in the battery bay, and connected the main hot cables and main ground cables to that battery. Such a battery wouldn’t last very long without shore power, but the idea is that having it in place allows shore power to be connected to the coach, thereby allowing the various electrical loads to function. It’s also important to lower the house battery bank Amp Hour setting so the inverters don’t over-charge the single 12-volt battery.

If you don’t already have a spare 12 volt battery sitting around, it wouldn’t make a lot of sense to buy one just for this purpose. But if you do, this approach might be something to consider. Even so, I still think the best approach is the one I outlined above. I realize it means two trips to the battery shop (which may or may not be all that close to where you are), but all things considered I still think that approach will be your best option.

Regarding what all to turn off before starting on the battery removal/replacement project, the only thing I’d add to your list would be to turn off the breaker on the generator. While it’s unlikely the generator would start on its own while you’re removing & replacing batteries, turning the breaker off will ensure that no 120 volt AC power from the generator reaches the coach if the generator should start for some weird reason.

Those are my thoughts. I’m sure others will chime in with additional advice.

[BaldDaddy]

Thanks Larry for your insight. I was thinking the same thing but figured I would ask anyhow. Unless someone else chimes in that it is doable, I will do the disconnect on Thursday late afternoon and just leave the coach powerless until Saturday morning when I can get the new batteries installed. I don’t see any harm in that other than defrosted refrigerators. Please correct me if I am wrong. The batteries are located 80+ miles away so would prefer not to have to do that up/back twice unless absolutely necessary.

[brobox]

Originally Posted by BaldDaddy

Thanks Larry for your insight. I was thinking the same thing but figured I would ask anyhow. Unless someone else chimes in that it is doable, I will do the disconnect on Thursday late afternoon and just leave the coach powerless until Saturday morning when I can get the new batteries installed. I don’t see any harm in that other than defrosted refrigerators. Please correct me if I am wrong. The batteries are located 80+ miles away so would prefer not to have to do that up/back twice unless absolutely necessary.

Here's a thought on the refrigerator. If you store where there is power, plug the refrigerator in with an extension cord. On the B model the refrigerator plugs in under the dinette table, not sure on the A.

[BaldDaddy]

Originally Posted by brobox

Here's a thought on the refrigerator. If you store where there is power, plug the refrigerator in with an extension cord. On the B model the refrigerator plugs in under the dinette table, not sure on the A.

Thanks Chuck for keeping things simple . Sometimes looking at the big, more complex picture, we are blind to the easy fixes. Coach is parked at my house so an extension cord will solve that inconvenience. Thankfully winter has finally made it far enough south for a few days that A/C won’t be necessary. Now to locate that plug!

[drwaynesmith]

The other two items you can disconnect that I didn't see mentioned are throw the battery interconnect lever, so you don't somehow get juice from the chassis batteries, and disconnect the wire from the solar charge controller, if you've got sunshine. Get a can of battery terminal cleaner (essentially, spray baking soda) and some fine sandpaper to clean the terminals. No need to put on a terminal protectant, they are not in a corrosive environment.

[brobox]

Originally Posted by BaldDaddy

Thanks Chuck for keeping things simple . Sometimes looking at the big, more complex picture, we are blind to the easy fixes. Coach is parked at my house so an extension cord will solve that inconvenience. Thankfully winter has finally made it far enough south for a few days that A/C won’t be necessary. Now to locate that plug!

Same situation the other day. Bedroom TV in the MH was mounted with screws that were to short, which split the 1x2 when it pulled loose. I was going to make a major woodworking project out of it. My neighbor looked at it and said, why don't you just use longer screws. Two heads are much better than one when looking at something damaged.

For others information, that damage was caused when I left the coach at a shop and they test drove it. Exactly why I rarely leave my coach. I won't make that mistake again.

[BaldDaddy]

Originally Posted by drwaynesmith

The other two items you can disconnect that I didn't see mentioned are throw the battery interconnect lever, so you don't somehow get juice from the chassis batteries, and disconnect the wire from the solar charge controller, if you've got sunshine. Get a can of battery terminal cleaner (essentially, spray baking soda) and some fine sandpaper to clean the terminals. No need to put on a terminal protectant, they are not in a corrosive environment.

Battery interconnect lever? Is that also behind the false panel in the basement near the house batteries? Where the ME-RVC Bridge is.

Larry — Checked the ME-RVC bridge version. I am on v1.2 as you mentioned. Going to reach out to Entegra on Monday and see what can be done about getting it updated, or should I say, how much is it going to cost me. Ha! Will also get their input about battery swap procedures and let you all know if they vary from what has already been mentioned.

Chuck — Unfortunately on the “A” the refrigerator plug doesn’t appear to be as obvious. The subwoofer is plugged in beneath the dinette. Murphy’s Law screwing up a great idea again. Will ask Entegra that question as well. Sorry to hear about the split 1x2 on a brand new coach. Happy that it was an easy fix.

[brobox]

Originally Posted by BaldDaddy

Chuck — Unfortunately on the “A” the refrigerator plug doesn’t appear to be as obvious. The subwoofer is plugged in beneath the dinette. Murphy’s Law screwing up a great idea again. Will ask Entegra that question as well. Sorry to hear about the split 1x2 on a brand new coach. Happy that it was an easy fix.

Just looked at the A floor plan, is there a plug in the pantry?

[BaldDaddy]

Originally Posted by brobox

Just looked at the A floor plan, is there a plug in the pantry?

Unfortunately not that I saw, nor in the overhead cabinets near the refrigerator. I suspect it may be behind it, similar to a residential installation. If that is the case, not worth the headache pulling it out.

[BaldDaddy]

So I installed the four (4) Lifelines this past weekend and was monitoring how the coach was behaving. Unfortunately it looks like I may have a problem with the outdated ME-RVC bridge. The coach has been in Absorb mode now for better than 6 hours but the batteries never get to the 14.3v it is set for.

In addition, being on 50A shore power, I check the coach each morning to find that one, the other, or both chargers on the VegaTouch showing as Not Charging. Is Not Charging the same as Full Charge with the Magnums? I have the VegaTouch in custom mode with 14.3v for Absorb, 13.3v for Float, and 15.5v for Equalize per the Lifeline spec.

Finally, I noticed that the Vegatouch is reporting a different battery voltage than the remote monitor above the door. Which too believe?

Thanks all.

[757driver]

Originally Posted by BaldDaddy

So I installed the four (4) Lifelines this past weekend and was monitoring how the coach was behaving. Unfortunately it looks like I may have a problem with the outdated ME-RVC bridge. The coach has been in Absorb mode now for better than 6 hours but the batteries never get to the 14.3v it is set for.

In addition, being on 50A shore power, I check the coach each morning to find that one, the other, or both chargers on the VegaTouch showing as Not Charging. Is Not Charging the same as Full Charge with the Magnums? I have the VegaTouch in custom mode with 14.3v for Absorb, 13.3v for Float, and 15.5v for Equalize per the Lifeline spec.

Finally, I noticed that the Vegatouch is reporting a different battery voltage than the remote monitor above the door. Which too believe?

Thanks all.

It does sound like the RVC bridge is not working properly. Not charging on the Vegatouch is the same as Full charge as long as the charger is enabled.

To know which voltage is correct measure at the batteries with a DVM.

[drwaynesmith]

My Vegatouch behaved like that with regard to absorb right after I put in 4 new Lifelines a few weeks ago. I do have an updated bridge. It seems to be ok now. The things I did along the way, in no particular order, was reboot, turn the chargers off and let the voltage drop gradually just from lights and pump, and then turn back on. The other thing I did was stop using custom, which I needed for my previous batteries, and use AGM1, which is Magnum built in setting for Lifelines. It only differs by 0.1 volts from your custom settings. That might be helpful, essentially with the old bridge.

I haven't tried a deeper discharge now to see how long absorb goes, but it's staying nicely in float/off.