Assumption - The Mother of All Screw-ups (Coach Batteries)

[Xplorer]

In at attempt to avoid the Assumption Label, I need to replace the 2 - 6v batteries in the below picture and replace them with 1 - 12v battery.

If my research is correct, all I need to do is connect the positive terminal wire to the positive post on the 12v battery,and the negative terminal wire to the

to the negative post on the 12v battery.

Am I missing anything?

We don't do a lot of boondocking, more than one night at a time while traveling. I assume, there's that word again,,,,,,that a 12v battery would be sufficient for our needs.

Again, if I'm missing something, help me prevent the Assumption Label.

Thanks in advance for the assistance and comments.

IF, another little troublemaker word,,,,,I am correct. Any suggestions on a 12v battery as a replacement for the 2 - 6v ones????

As you can see the below batteries are NAPA,,,,,2 years and 1 month of service........

[wolfe10]

If you want to replace the two 6 VDC with a single 12 VDC battery you are exactly correct on how to do it.

House ground, now on left battery negative would go to 12 volt battery negative.

House positive, now on right battery positive would go to 12 volt battery positive.

But, since you are already set up for 6 VDC batteries, and golf cart batteries are the least expensive way to get deep cycle batteries, I am not sure what you will gain by the move.

Assuming you occasionally want to be able to overnight without shore power/generator, 220 amp hrs at 12 VDC (approximately what you have in the two golf cart batteries) is really about a minimum anyway.

Brett

[Xplorer]

Brett, thanks for the quick response.

I thought I would be able to cut costs with the one 12v battery.

Seems the most service I have been able to get out of any of the "mainline" batteries is 2 years.

Based on what you are saying, Maybe I'm looking in the wrong places for the 6v batteries.

Next ???, where is the best and most economical location to purchase the 2 6v batteries/

I'm not confident I would get more than 2 years out of any battery regardless of the cost.

I looked at the sites for the high end batteries, trojan, etc., and retailers are not conveniently located.

If, I have an issue before warranties expire, I would like the convenience of locating a dealer almost anywhere.

Thanks again for your confirmation in ensuring I don't contribute to the Assumption tag.

Regards

John

[wolfe10]

John,

As long as you are not severely overchaging them or allowing then to be very deeply discharged and keep water level up, they should last a lot more than 2 years.

Many buy golf cart batteries at Sams/Walmart, as they have locations everywhere.

I go a different direction when it comes to batteries and use high-end AGM's-- Lifelines for house and Optimas for starting. Both are 7 years old and going strong. BUT, they ae not abused by incorrect charging or deep discharging.

It is VERY difficult/expensive to find a quality 12 VDC deep cycle battery. Much easier to find them in 6 VDC, as that is what golf cart batteries are. Said another way, I suspect you will pay as much for a quality deep cycle 12 VDC battery of lesser capacity as you will for two golf cart batteries of the same quality and the golf cart batteries will have more capacity.

Brett

[Xplorer]

I keep the MH plugged in while in storage which at the most is 3 months, and not very often. We can't sit for 3 months unless we are involved in some volunteer endeavor.

We do stay put for 3-4 months at times between trips. I clean and use the battery spray for the terminals if I notice any corrosive buiidup, etc.

I regularly check the water level and use distilled water when needed.

I keep the fridge on, as we keep items in the freezer, etc ready to go. Although plugged in, typically it has some drain with the fridge.

I use a bayonet disconnect on the Chassis battery, and I never have any issues with it.

Thanks for all your input on FMCA. Good sound advice. I'll take a look at the Walmart Golf cart batteries.

Thanks again.

[wolfe10]

Use a digital voltmeter to check charging voltage at the battery. Should be in the 13.2- 13.5 VDC range if left plugged in.

How often do you have to add how much water?

[Xplorer]

I'll do that on the voltage check.

It varies, the last time i had it in storage, I added distilled water once during the 3 months.

When park at an RV site, I have gone 6+ months with the water level ok.

It seems as though when in storage more water is used. I had it in storage for 4 months from December to April, and because we went east, I did not leave it plugged in during that time, because I would not be able to check the batteries. The water level was fine when I left.

It has been plugged in since May, with the exception of a short one week trip, and all was well. Returned plugged the unit in. That's when I again checked the water level and added a little water.

Since returning from the one week trip, the battery monitor kept declining over the last weeks or so. I expected the batteries were going bad. Now, they aren't charging. There is still enough power to operate the steps, and dull lighting. That may be a result of still being plugged into a 15 amp circuit.

Anyway, this is basically the same thing that happened the last time I replaced the batteries, except we were using the Motorhome fultime at that time.

Maybe there is another villain I need to look at.

Thanks again for the comments.

[Xplorer]

On the primary battery or the right battery its 13.2

And the left or secondary its just over 12 if Im reading it right.

[wolfe10]

To check the batteries in the photo, negative lead on the negative of battery on the left side (where cable goes to house ground) and positive on the positive of right battery (where house positive connects). Fully charged battery (actually two together)= 12.7 VDC. Anything above that suggest the converter is working (with converter on, should be 13.2-13.5). 12.2 is a 50% discharged 12 VDC battery.

If you were talking about another battery bank , "just over 12" shows a mostly discharged battery (12.2 VDC is a 50% discharged 12 volt battery as measured with the battery at rest). If you don't have a way to charge that battery, suggest you get one.

Brett

[RVerOnTheMove]

If you were measuring each batteries voltage they would read somewhere around 6.6V if fully charged. Since you are measuring the 2 together as one bank then the voltage is read only on the + post on one battery and the - post on the other battery.

[Xplorer]

To check the batteries in the photo, negative lead on the negative of battery on the left side (where cable goes to house ground) and positive on the positive of right battery (where house positive connects.

If you were talking about another battery bank , "just over 12" shows a mostly discharged battery (12.2 VDC is a 50% discharged 12 volt battery as measured with the battery at rest). If you don't have a way to charge that battery, suggest you get one.

Brett

If you were measuring each batteries voltage they would read somewhere around 6.6V if fully charged. Since you are measuring the 2 together as one bank then the voltage is read only on the + post on one battery and the - post on the other battery.

Back to battery school tomorrow. I'll redo the testing as indicated. I tested across each battery, and also as Brett indicated. Obviously I'm doing something wrong or reading the meter incorrectly. I do have a charger. Why wouldn't the converter maintain the charge if the batteries were ok?.

I understand the basics of the 12v system, it's just the innards I'm not sure about. I have an IOTA converter.

I appreciate the education, at the expense of looking foolish. I am going to understand this stuff one way or another, testing, etc.

Thanks again.

[RVerOnTheMove]

Please don't take anything post here by anyone as an indication that we think anything you have said or done is foolish. Learning is a process and we are all willing to help you learn. Once you are done learning about batteries there will be something else and then something else and then......

[Xplorer]

Please don't take anything post here by anyone as an indication that we think anything you have said or done is foolish. Learning is a process and we are all willing to help you learn. Once you are done learning about batteries there will be something else and then something else and then......

Thanks for the comment, and patience you and Brett have demonstrated.

As indicated, I have a battery charger. Can the batteries be charged while still connected to the MH?

If, so, I assume (that word again), I would unplug the coach before charging.

AND,

Would the charger be connected to the right positve side of the battery bank, and the negative to the negative cable connected to the coach, causing both batteries to be charged, or do the have to be charged individually? By connecting the charger to the positive and negative post on each battery one battery at a time.

[RVerOnTheMove]

If you are going to use a 12V charger, I would just disconnect the + and - connections that go to the coach, leave the center jumper and connect the charger to the posts you just disconnected. This will isolate the batteries and allow them to at least attempt a charge. If you think the coach will need to have 12V power while you are doing this then you would want to unplug or disconnect the converter and leave all of the battery cables connected. I suspect that you are going to find that one battery is good and one is bad based upon one of your earlier posts so you may want to take them to a local battery store and have them load tested. If you find you have to replace one, you really need to replace both. Something like this 225AH battery would be a good choice.

http://www.ebay.com/...ain_100&vxp=mtr

So others (cheaper and not) can be found here:

http://www.google.com/products/catalog?hl=en&rls=com.microsoft:en-us:IE-Address&q=trojan+t105+battery&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&biw=1171&bih=572&wrapid=tlif134023832826510&um=1&ie=UTF-8&tbm=shop&cid=14829542272397574964&sa=X&ei=6WniT-qQBeKC2wXIg5ncCw&ved=0CJUBEPMCMAM#scoring=tp

[Xplorer]

If you are going to use a 12V charger, I would just disconnect the + and - connections that go to the coach, leave the center jumper and connect the charger to the posts you just disconnected. This will isolate the batteries and allow them to at least attempt a charge. If you think the coach will need to have 12V power while you are doing this then you would want to unplug or disconnect the converter and leave all of the battery cables connected. I suspect that you are going to find that one battery is good and one is bad based upon one of your earlier posts so you may want to take them to a local battery store and have them load tested. If you find you have to replace one, you really need to replace both. Something like this 225AH battery would be a good choice.

http://www.ebay.com/...ain_100&vxp=mtr

In the past, I've just taken them in, thought I would work through the process as far as I could this go around, but the simple solution may be just to take them in.

Just curious, can batteries be load tested while in the MH? Or do they have to be removed?

I have some time before we take off again, that's why I'm playing around trying to resolve and learn something at the same time.

I have sure learned a lo from the 2 forums I track, over the years.

Again, I sincerely appreciate you and Brett taking the time to educate me in this process.

When I get it all resolved, I'll post my final results.

Thanks again.

[RVerOnTheMove]

Batteries can be loaded tested in any location as long as they are disconnected from each other and from any other load (+ and - cables disconnected).

If you can take them in and charge them with a 6V charger separately that would be best as the batteries must be fully charged in order to do a proper load test. If a battery will not properly charge you are done and the battery needs replacing.

[Xplorer]

Batteries can be loaded tested in any location as long as they are disconnected from each other and from any other load (+ and - cables disconnected).

If you can take them in and charge them with a 6V charger separately that would be best as the batteries must be fully charged in order to do a proper load test. If a battery will not properly charge you are done and the battery needs replacing.

Lest I forget to say thanks again for all the 12v battery education.

Thanks for yours and Brett's responses.

I'll resolve the battery issue today or tomorrow.

Thanks again.

[Xplorer]

Thanks again for all the comments and insight.

I decided on 2 Trojan t105's I found at a local golf cart dealer.

Trojan website didn't list them.

Wally did not carry any 6 volt batteries.

The napas were dead.

Hopefully when I install the trojans all will be good.

Thanks again.

John

[wolfe10]

Yes, the Trojan T105 is a very popular and good quality golf cart battery. The two in series will give you 225 amp-hrs @12 VDC or up to a usable 112 amp-hrs if the batteries are fully charged before you should recharge them (discharging below 50% charge materially shortens a battery's life).

From Trojan's website: http://www.trojanbat...ts/T-1056V.aspx

[Xplorer]

Installed the 2 Trojan T105's, and the battery monitor sure is purty.

Everything seems to be working according to Hoyle......

The fridge is on, I'll check it in a few hours to see if it will cool the Lone Star, Mexican Ice Tea, Sangria, et.al.

Between picking up the batteries, and installing them,,,,

Had the fan clutch and water pump replaced on the Jeep. I'm doing my part for the economy. I helped keep someone employed today.

Everything done by 1:30 p.m,,,,,fed the deer, kicking back in the lounger with feet up watching the clock until the big hand is on 12 and the little hand on 5.

It has to be 5pm somewhere,,,,,,,In the meantime, life is good.

Thanks for all the help, advice and education.......

[Xplorer]

Life was good,

Assumption The Sequel:

Went over to the MH to check the power, fridge, etc.....

Well, the battery monitored showed nothing. The fridge lights were off. The 110v power meter plugged into the socket showed power.

Reset the 12v house power switch. I know it was on when I left.

After resetting the 12v switch, the 12v power monitor returned to fully charged. The lights on the fridge were on, other 12v pumps, lights worked.

What would cause the 12v house switch to go off, if that is what happened?

I'm going back and recheck later.

If the 12v switch has to be reset again, what would cause it to automatically turn off. Is it a bad rocker switch? Or something else?

Just when I was looking forward to 5pm.

Again, any thoughts are appreciated.

[RVerOnTheMove]

Where is the cutoff located. I have seen coach's where it was very easy to brush against it on the way in our out of the coach without noticing.

I am not aware of anything that would "trip" that kind of a switch.

[wolfe10]

Depends on what kind of control you have for your battery disconnect switch.

Assume this is a switch controlling a solenoid, not mechanical switch.

Did it "turn itself off" after the new batteries were installed and all connections tightened? If so strange. If this happened when the old batteries were taken out and new ones were installed, it is possible that loosing all 12 VDC turned the solenoid off (depends on the type of solenoid).

I would monitor it and see if it reoccurs. If it does, get us more information on what battery disconnect switch and solenoid you have.

Brett

[Xplorer]

Bill & Brett,

It's a rocker switch in a row of rocker switches for the steps inside/outside light; located inside the doorway at the bottom of the cabinet.

I just got back from checking again. Everything is on and fine.

If it continues, I'll check the info and provide more detail info.

I am positive it was on the first time, because I checked the fridge, monitor before walking out the door.

I thought it was strange as I knew it was on.

In the past DW shut it off by mistake. That was interesting before I remembered to check it.

I will probably go over and check again before dark.

Unless,,,,,,,when I turned it back on after installing the new batteries it was not seated and the vibration of closing the door, etc, caused it to shut off. Just grasping.

sure was weird to go in and find all 12v off. oh well, that's life in the RV Lane.

Thanks for your thoughts on this continuing saga. Electrical gremlins.

[RVerOnTheMove]

That's the exact location of the switches I have seen accidentally shut off as I suggested above. Since the DW has done this in the past I would put my money on the fact that you did it as well. Hopefully, you will find that when left alone, the power will remain!

Let us know.