Replacing 12 volt house batt
- Thread starter Cuervo1
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Gizmo100
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Cuervo1 said:
YES
You wire two six volt batteries in series to make one BIG 12 volt.
Lou Schneider
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Welcome to The RV Forum!
Yes you can, and many people have done this. Just connect the two 6 volt batteries in series to make a single large 12 volt battery.
Parallel connections are like you have now. Two wires, one going from each battery's (+) and (-) post to the same on the other battery.
Series connection is a SINGLE wire going from the (+) post on one battery to the (-) post on the other. This makes the two 6 volt batteries into a 12 volt battery. All of the wires going to the RV connect to the remaining (+) and (-) posts.
Yes you can, and many people have done this. Just connect the two 6 volt batteries in series to make a single large 12 volt battery.
Parallel connections are like you have now. Two wires, one going from each battery's (+) and (-) post to the same on the other battery.
Series connection is a SINGLE wire going from the (+) post on one battery to the (-) post on the other. This makes the two 6 volt batteries into a 12 volt battery. All of the wires going to the RV connect to the remaining (+) and (-) posts.
John From Detroit
Well-known member
Not only can they (USUALLY) but it is also usually a good idea.. I will list the considerations and the reasons
Why did I say they USUALLY Can?
THe GC-2 is the most common six volt battery two of them in series makes for one BIG (220 amp hour give or take a bit) 12 volt battery.. In fact once you have them in place think of them as a single 12 volt... Roughly a 4D. IN SOME CASES however. there is not enough room for them as they are TALLER than most 12 volt batteries so before you buy. use a tape measure to measure.
YOu also hook them up in series lIke this -{6v}+==-{6V}+
where the 12's are hooked in parallel
-{12 volt}+
-{12 volt}+
There are some additional advantages to a true DEEP CYCLE battery like a GOlf Car (GC) over a MARINE/deep cycle which is what most (not all) RV 12 volt batteires are.
THe other consideration is capacity. For DEEP CYCLE you can safely use half. or 110 amp hours per pair of GC2 For most MARINE/deep cycles you can safely use 1/4
Group 24 are about 70-75 amp hours
Group 27/29 just under/over 100
Group 31 130 Most of these Group # are MARINE/deep cycle (See 25% comment above)
4d And 8D around 200-240 (Same as GC-2 pairs) These are fairly easy to find in DEEP CYCLE as well as other types. But heavy and expensive.
GC-2 are also very very very poplar as every golf course from here to there and back again buy's em by the pallet load...
SO they are cheaper
Why did I say they USUALLY Can?
THe GC-2 is the most common six volt battery two of them in series makes for one BIG (220 amp hour give or take a bit) 12 volt battery.. In fact once you have them in place think of them as a single 12 volt... Roughly a 4D. IN SOME CASES however. there is not enough room for them as they are TALLER than most 12 volt batteries so before you buy. use a tape measure to measure.
YOu also hook them up in series lIke this -{6v}+==-{6V}+
where the 12's are hooked in parallel
-{12 volt}+
-{12 volt}+
There are some additional advantages to a true DEEP CYCLE battery like a GOlf Car (GC) over a MARINE/deep cycle which is what most (not all) RV 12 volt batteires are.
THe other consideration is capacity. For DEEP CYCLE you can safely use half. or 110 amp hours per pair of GC2 For most MARINE/deep cycles you can safely use 1/4
Group 24 are about 70-75 amp hours
Group 27/29 just under/over 100
Group 31 130 Most of these Group # are MARINE/deep cycle (See 25% comment above)
4d And 8D around 200-240 (Same as GC-2 pairs) These are fairly easy to find in DEEP CYCLE as well as other types. But heavy and expensive.
GC-2 are also very very very poplar as every golf course from here to there and back again buy's em by the pallet load...
SO they are cheaper
Kevin Means
Site Team
All good replys. The only thing I'd add is, make sure you measure your battery compartment before you buy 6 volt GC batteries. They're taller than the 12 volt batteries that are typically installed in RVs. They won't fit in our battery compartment - too tall.
Kev
Kev
Bobtop46
Well-known member
Thanks, found GC-2 at Sam's for $90. I will get them after I measure the comprtment. Hope they will fit. If not it will be 12 volt again, mine have had it. I have Exide now, lasted 5 years. Is there a particular brand that anyone would reccomend?
John From Detroit
Well-known member
Trojan is considered best
Interstate or Deka (More on Deka shortly) are good.
Lifeline if you go AGM
Avoid Optima
Excide used to be a battery I would not recommend but from what I have heard they have impoved over the last decade or two.
DEKA is East Penn Battery company.. There is one company in the US that can process raw lead into the final product (Smelting it's called) and that is East Penn Battery companuy All others import their lead. MY GC-2's are DEKA and are 4 years PLUS old.. I've had to add water (distilled) to them once. this spring. in that 4 years.
The Interstates they replaced lasted 9 years and needed annual watering when new more frequent as they aged.
Interstate or Deka (More on Deka shortly) are good.
Lifeline if you go AGM
Avoid Optima
Excide used to be a battery I would not recommend but from what I have heard they have impoved over the last decade or two.
DEKA is East Penn Battery company.. There is one company in the US that can process raw lead into the final product (Smelting it's called) and that is East Penn Battery companuy All others import their lead. MY GC-2's are DEKA and are 4 years PLUS old.. I've had to add water (distilled) to them once. this spring. in that 4 years.
The Interstates they replaced lasted 9 years and needed annual watering when new more frequent as they aged.
Arch Hoagland
Well-known member
Might I suggest you take a picture of the current setup BEFORE you disconnect everything.
The new 6 volt batteries are going to be wired differently but in case you have to go back to the original setup you will have a picture of how it was.
The new 6 volt batteries are going to be wired differently but in case you have to go back to the original setup you will have a picture of how it was.
Lou Schneider
Site Team
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Duracell brand lead acid golf cart and automotive batteries are made by East Penn.
Isaac-1
Well-known member
One other thing to keep in mind, GC2 6 volt batteries are also slightly wider than typical 12V automotive batteries (7.125 inches vs 6.8 inches, with slight brand to brand variation). When I installed mine it was so tight I had to clean out the dirt and grime from the steel battery tray, and even then I had to spread the edge apart slightly (1/16'th of an inch or less) as only one end of the battery would go into the groove (close enough to be within manufacturing tolerance on the welded steel battery tray)
Utclmjmpr
Well-known member
IF you have the room,, place a 1/4 inch (or more) separator (wood) between the battery cases to improve cooling.>>>Dan
Gary RV_Wizard
Site Team
That 1/4" separator should be to be a narrow strip rather than the full size of the battery sides. The idea is to enable air flow between the sides of the adjacent batteries.
However, that spacing is not needed as long as the batteries are in good condition and the charger is reasonably "smart" (3-stage charging). The batteries won't get excessively warm if those conditions are met. If they really need extra cooling, it's arguably time to replace then.
Another note: Better quality chargers have temperature compensation and the best have a temperature sensor that goes between the batteries or sticks to the side of one of them. It adjusts the charge voltage to the optimum level for the actual battery temperature.
However, that spacing is not needed as long as the batteries are in good condition and the charger is reasonably "smart" (3-stage charging). The batteries won't get excessively warm if those conditions are met. If they really need extra cooling, it's arguably time to replace then.
Another note: Better quality chargers have temperature compensation and the best have a temperature sensor that goes between the batteries or sticks to the side of one of them. It adjusts the charge voltage to the optimum level for the actual battery temperature.
While six volt golf cart batteries are a popular option to replace one or two 12 volt batteries, most of the advantages are lost if replacing with AGM batteries. AGM 12 volt batteries are true deep cycle, weigh less than comparable six volt AGM golf cart batteries, cost less than 6 volt AGM , and have close to the same amp hours (two six volt for 220 amp hours or 200 amp hours for two 12 volt). The 12 volt AGM are close to the same size as flooded 12 volt. And, if installed in pairs, if one 12 volt goes prematurely bad, just remove the bad one and continue your trip.
Gary RV_Wizard
Site Team
LTG is right on target, except that the amp-hours of a 12v AGM vary with the case size. To get 100 AH each in a 12v AGM, a Group 27 size is needed. A Group 31 would be around 112-115 AH each. And most 6v GC2 AGMs are about 200 AH (vs 220-225 for a flooded cell GC2 6V).
The advantage of a 6V GC2 deep cycle vs a 12v deep cycle is strictly price. 12v deep cycles are a limited production specialty battery and relatively high-priced, whereas the 6v GC2 "golf car" battery is a high volume sales item with much better pricing.
The advantage of a 6V GC2 deep cycle vs a 12v deep cycle is strictly price. 12v deep cycles are a limited production specialty battery and relatively high-priced, whereas the 6v GC2 "golf car" battery is a high volume sales item with much better pricing.
John From Detroit
Well-known member
LTG I will make one comment on the "Weigh less" part.
THough we talk about Amp Hours.. It is WATT HOURS that count... (Watt hours = 12 times amp horus. Linier for the most part)
So a batery with 110 amp; hours at 12 volts holds the same watt hours as one that is 6 V at 220 amp hours (GC-2) .... But of course two of either = Identical power .
AND no matter if AGM or Maintenance free Or Flooded wet cell. 220 amp hours at 12 volts will be within one pound of each other.. two at the most. Not enough to even notice.
I looked at teh DEKA Chart a G-10 (One of their GC-2 size) is 210 AH at 6 volt and 60 pounds so for 210 AH at 12 volt you'd have 120 pounds.
A pair of 31Ms (AGM) 105 AH each woudl be the ame 210 amp hours but 135 pounds.
So they would be a NEGATIVE 5 pounds lighter (That's 5 pounds heavier)
Same manufacture Same AMp hours.> NOTE I have G-20's in my house (more power more power).
THough we talk about Amp Hours.. It is WATT HOURS that count... (Watt hours = 12 times amp horus. Linier for the most part)
So a batery with 110 amp; hours at 12 volts holds the same watt hours as one that is 6 V at 220 amp hours (GC-2) .... But of course two of either = Identical power .
AND no matter if AGM or Maintenance free Or Flooded wet cell. 220 amp hours at 12 volts will be within one pound of each other.. two at the most. Not enough to even notice.
I looked at teh DEKA Chart a G-10 (One of their GC-2 size) is 210 AH at 6 volt and 60 pounds so for 210 AH at 12 volt you'd have 120 pounds.
A pair of 31Ms (AGM) 105 AH each woudl be the ame 210 amp hours but 135 pounds.
So they would be a NEGATIVE 5 pounds lighter (That's 5 pounds heavier)
Same manufacture Same AMp hours.> NOTE I have G-20's in my house (more power more power).
John From Detroit,
Would the two 220 Amp Hour 6 volt batteries in my post weigh less than the two 100 Amp Hour 12 volt batteries in my Post? I specifically used 27 group batteries as an example in my post because I doubt if the OP's Forest River motorhome has group 31 batteries.
Would the two 220 Amp Hour 6 volt batteries in my post weigh less than the two 100 Amp Hour 12 volt batteries in my Post? I specifically used 27 group batteries as an example in my post because I doubt if the OP's Forest River motorhome has group 31 batteries.
John From Detroit
A Deka GC2 6 volt AGM battery is 190 Amp Hours at the 20 amp hour rate and weighs 70 pounds. A Deka group 31 12 volt AGM battery is 105 Amp Hours at the 20 amp hour rate and weighs 69 pounds. This from the Deka website. So, two group 31 AGM batteries have 20 more amp hours and weigh 2 pounds less than 2 GC2 AGM batteries.
A Deka GC2 6 volt AGM battery is 190 Amp Hours at the 20 amp hour rate and weighs 70 pounds. A Deka group 31 12 volt AGM battery is 105 Amp Hours at the 20 amp hour rate and weighs 69 pounds. This from the Deka website. So, two group 31 AGM batteries have 20 more amp hours and weigh 2 pounds less than 2 GC2 AGM batteries.
Utclmjmpr
Well-known member
There is really no magic about it,, more lead is more battery.>>>D
