Replacing four CG 6 volts with two Group 27?

I would stay with the GC-2 batteries.
I would check on your converter to insure it is more of a spart charger. I replaced the converter and was surprised on how much lower batteries last.

Four six volt GC=2 is 440 amp hours of which 220 are usable

Two group 27's is about 200 amp; hours of which you can use 40-50

Are you sure you don't want to remember to water more often??????

I vote for two AMG 6ers since you seldom dry camp.

Maintenance free means you can't add water. If your converter is cooking batteries and you can't add water your problem will be worse. I'd get a better converter first. After that. If you never dry camp any ole battery will do.

Go for it.

KD4UPL wrote:
Maintenance free means you can't add water. If your converter is cooking batteries and you can't add water your problem will be worse. I'd get a better converter first. After that. If you never dry camp any ole battery will do.

My maintenance free start batteries are on the same converter (Xantrex Freedom 3 stage) and are good at 8-9 years. That’s what prompted the thought.

"Two group 27's is about 200 amp; hours of which you can use 40-50'"


More internet fuzzy math... {Keep in mind that there are 3 kinds of people on this planet, those that can do math and those that can't.} :B Two group 27's that offer a total of 200 amps give you 100 useable amps, not 40 - 50.

Most folks overestimate how much DC they actually use {Spending lots of time and money searching for a solution for which there is no known problem... the government does this a lot}.
:S

Our two, 4 year old, Interstate Group 27 {true} deep cycle batteries give us an easy 3 - 4 days of normal use off of the grid. Since we rarely stay in one place for more than 3 or 4 days and driving just a few hours tops them up nicely we rarely run the generator. Our coach is 7 years old and the genny has 85 hours on it and yes we are off the grid most {60 - 70 percent} of the time.

We don't have slides or electric steps, don't watch TV or movies, just a couple of hours of lights at night - I read and my bride journals {absolutely no reason to spend the $$ for LED's}. The water pump draws so little as to not even be a consideration.

The one big draw is the furnace {the squirrel cage fan} but with a 35K BTU furnace it runs so little as to not be much of a factor and then only for a few months of the year {yes we RV year round out here in southern Arizona}.

My batteries require regular topping up and that frankly is a PITA. I may spring for AGM's when these finally start to go but at more than twice the price I will probably suck it up and keep watering them.

One thing I learned in 35+ years of boating is that the two biggest lies in the English language are:

Waterproof and maintenance free.

As always... Opinions and YMMV

:C

Desert Captain wrote:
"Two group 27's is about 200 amp; hours of which you can use 40-50'"


More internet fuzzy math... {Keep in mind that there are 3 kinds of people on this planet, those that can do math and those that can't.} :B Two group 27's that offer a total of 200 amps give you 100 useable amps, not 40 - 50.

Most folks overestimate how much DC they actually use {Spending lots of time and money searching for a solution for which there is no known problem... the government does this a lot}.
:S

Our two, 4 year old, Interstate Group 27 {true} deep cycle batteries give us an easy 3 - 4 days of normal use off of the grid. Since we rarely stay in one place for more than 3 or 4 days and driving just a few hours tops them up nicely we rarely run the generator. Our coach is 7 years old and the genny has 85 hours on it and yes we are off the grid most {60 - 70 percent} of the time.

We don't have slides or electric steps, don't watch TV or movies, just a couple of hours of lights at night - I read and my bride journals {absolutely no reason to spend the $$ for LED's}. The water pump draws so little as to not even be a consideration.

The one big draw is the furnace {the squirrel cage fan} but with a 35K BTU furnace it runs so little as to not be much of a factor and then only for a few months of the year {yes we RV year round out here in southern Arizona}.

My batteries require regular topping up and that frankly is a PITA. I may spring for AGM's when these finally start to go but at more than twice the price I will probably suck it up and keep watering them.

One thing I learned in 35+ years of boating is that the two biggest lies in the English language are:

Waterproof and maintenance free.

As always... Opinions and YMMV

:C

Thanks.

My old 97 Holiday Rambler had one Group 27 and we ran the furnace all night on it, never had a problem.

We just don’t go where there is no electric.

The Tampa RV show every three years or so.

And you run your gen during the day.

My big concern would be could the 2000 watt inverter could damage the batteries if someone ran the microwave and I think they could handle it.

It just me a DW and she’s pretty smart.

Big Katuna wrote:
My four six volt batteries need replacing Again. Five years again and shot. I have a watering system but I leave the rv plugged in all the time and I forget to water them and they dry out.

Im pretty sure Im going to replace them with two Group 27 12vdc dual purpose maintenance free batteries. I chose those as the have the same footprint as the CGs and fit the rack.

I just replaced my 8 year old Group 31 starting batteries.
They were starting her just fine but I felt they were too old

We never boondock, we dry camp maybe once a year. I have replaced all the light bulbs with LEDs and the tv is LED too.

It has a 2000 watt inverter which might get used with tv. The microwave would get unplugged if boondocking.

Crazy? Stupid? Saves about $300 and some maintenance. Easier to change out, too

Whatever you decide, I'd go with AGM's.
Our coach came with four 12 AGM's that someone changed to 6v wet cells. I changed it back again, like the OEM.
Hate fooling around with watering and checking and especially when there's not a lot of room for doing so.
Not only that, our rig has the inverter/charger in the same compartment, with a rubber seal and some vents behind the batteries.
Don't like that either and even if fumes, might not be a problem.
Already had a chassis battery go bad and overheating enough for producing fumes and for setting off the propane detector inside the coach.
Had two boiling house batteries in a previous coach, so again, not very fond of wet cells of any kind and should have probably not replaced my chassis batteries with the standards and even though, they're maintenance free. If for no other reason, I'm beginning to wonder how the charger likes charging unlike cells in parallel, when the big boy relay is closed.

Go over to Royal Battery in Holly Hill and buy 2 Full River GC2 DC250-6 batteries, set the inverter charger for them.