Why would one battery of 3 be very low on water?

[TimLoon]

Have had the MH 5 years (2004 model) and the current set of batteries is 3 years old. I run 3- 6 volt(not looking for opinions on this unless relative) and have never had an issue. Today while getting ready to cover I decided to check battery fluid levels. Two were fine and the third was very low. The low battery was the independent battery wired in series. Rarely do I need to add water and MH is always plugged in when not on the road. Any ideas what could cause this?

[TimLoon]

Thank you to all the folks that offered constructive advice. I especially appreciate those that PM'd me. Best way to stay out of the fray. Not sure why one person seems to be on a vendetta of sorts to validate my statements by searching back several years. I guess that may be the same as calling me a liar. I am on several forums beyond this and can't say I have ever come away feeling like this. Might as well ask the moderator to close the thread as those that PM'd me fully answered my questions with great explanations.

[Bobbo]

I bet a dollar to a donut that the person who said this was a good idea was the one selling the three batteries. Suggestive selling. He upped his sale by 50%. Not bad.

[BCRacing24]

Bobbo wrote:
12v group 24 batteries run about 80 amp hours each, so 3 of them would give you about 240 amp hours.

12v group 27 batteries run about 90 amp hours each, so 3 of them would give you about 270 amp hours.

12v group 31 batteries run about 125 amp hours each, so 3 of them would give you about 375 amp hours.

6v golf cart batteries give you about 220 amp hours, so 2 of them give you about 220 amp hours.

This web site has useful general information:

http://www.batterystuff.com/kb/tools/bci-battery-group-sizes.html

You are spot on, another thing to consider the (3)-31's "should" only be discharged down to 60% which would give you 150 a/hrs of usable energy. While (2) GC2's can be discharged down to 40% conservatively which would give you 138 a/hrs. I would take 12 a/hrs less power for batteries that will charge faster via solar & last twice as long personally..... Agree??

[Boon_Docker]

There was a discussion here from 5 years ago about connecting three 6v's.

[mkirsch]

I want to know where the OP got a 50/50 response ORIGINALLY, three years ago, when he set this up. Not talking about this thread.

I really want to identify the ones who thought it was a good thing to do.

[2oldman]

Almot wrote:
Watch out, or your posts will disappear same as few mine....There was a condition in the very 1st post - not to offer opinions.

I had that happen on another thread yesterday. No opinions unless 'relative'. Maybe he meant only from his relatives.

[Almot]

2oldman wrote:

mkirsch wrote:
I would like to know on what planet was the opinion split "50/50" on whether your 3-battery configuration was ok or not.

It's called free advice.

NO! It's called "an opinion".
Watch out, or your posts will disappear same as few mine. There was a condition in the very 1st post - not to offer opinions. How the question on low water can be answered without offering an opinion on correct/incorrect wiring (or how could anyone other than half-literate salesman consider it correct) - is beyond me. I give up :), roger and out

[mkirsch]

2oldman wrote:

mkirsch wrote:
I would like to know on what planet was the opinion split "50/50" on whether your 3-battery configuration was ok or not.

It's called free advice.

It wasn't this forum. I searched the archives back to when the OP bought the motorhome, and the only battery related posts were regarding the ones that came in the coach originally. Nothing about a three-6V configuration.

[2oldman]

mkirsch wrote:
I would like to know on what planet was the opinion split "50/50" on whether your 3-battery configuration was ok or not.

It's called free advice.

[mkirsch]

The two that were in parallel are fine and in about the same condition. I bet you'll be able to get at least another summer out of running them in a two-6V-in-series configuration.

Take the third dead/dry battery out and save it for a core to exchange when it comes time for new batteries.

I would like to know on what planet was the opinion split "50/50" on whether your 3-battery configuration was ok or not. Right here pretty much 100% of us are scratching our heads asking, "WHY?"

If you received a 50/50 response, where are the people that said it was okay? They should be here arguing with the rest of 'em. The laws of physics have not changed in 3 years.

[MEXICOWANDERER]

One servant serving two masters dies early...

No one is getting this unfortunately. MEASURE the voltage across any one battery and compare it to the other two. This configuration will work for awhile but costs the common battery's lifespan. Like configuring a three wheel inline bicycle.

[Almot]

CA Traveler wrote:
you can get more AHs with 3 12s depending upon space and battery size.

But parallel batteries should be wired in a balanced manner for maximum performance and battery life. For 3 in parallel this means a completely different wiring setup setup for the batteries.

Yes. See Diagram #2 Here. #1 is Unbalanced wiring. #2 is "almost balanced" - much better than #1 and is not complicated, you can use the same interconnect cables.

[CA_Traveler]

TimLoon wrote:
Well, at least it was an interesting discussion. Last question: With 3 battery spaces, am I better off with the 2-6V or 3 - 12 volt?

You should be OK with 2 6s but you can get more AHs with 3 12s depending upon space and battery size.

But parallel batteries should be wired in a balanced manner for maximum performance and battery life. For 3 in parallel this means a completely different wiring setup setup for the batteries. Although unbalanced wiring will work this is just a FYI. Lot's of information available on balanced battery wiring.

[time2roll]

2oldman wrote:
I'll be darned if I can come up with any other way to make 12v from 3-6v batteries.

Leave one at the store....