House batteries

[zzpopz76@gmail.com]

Is it possible as I have been told by RV dealer to replace my 4-6v house batteries with 2-12v batteries? he said if I didnt boondock for more than a week at a time the 12v batteries would do fine as we would be drawing the same amps as 4-6v? we dont boondock more than a week at a time anyway so its a way to go.we are fultimers and usually are in a park with full hookups.

[wolfe10]

Is it possible as I have been told by RV dealer to replace my 4-6v house batteries with 2-12v batteries? he said if I didn't boondock for more than a week at a time the 12v batteries would do fine as we would be drawing the same amps as 4-6v? we don't boondock more than a week at a time anyway so its a way to go.we are fultimers and usually are in a park with full hookups.

Welcome to the FMCA Forum.

I would question the advice you have received. There is NO battery bank of 4 6VDC or 2 12 VDC batteries that will last a week while dry camping unless you are EXTREMELY frugal.

The least expensive quality deep cycle batteries (the proper battery for the house battery bank) are 6 VDC golf cart batteries.

Yes 12 VDC deep cycle batteries are available, but are quite a lot more expensive per amp-hr as they are relatively unique compared with golf cart batteries. And 12`VDC deep cycle batteries come in a wide range of sizes (in amp-hrs), so, depending on what 12 VDC battery was recommended, you may or may not be stepping down in capacity. Marine or combination start/deep cycle batteries are a BIG step down for deep cycle use from true deep cycle batteries. Avoid them.

Most define their battery bank size as "proper" if they can go overnight without discharging the batteries below 50% (1/2 their rated amp-hr capacity). If dry camping very often, the equation becomes overnight while discharging the batteries from 85% to 50%. That is because it is a lot less efficient to top off the last 15% than to run them from 50% to 85%. And discharge below 50% materially shortens battery life.

Check with your local Sams and Cosco as well as golf shops. I will pay a little more for Trojan T105's than "standard" GC batteries.

If you don't plan to run much on an inverter or run the furnace (the furnace fan is a 12 VDC power hog), you may be able to get away with a single pair of GC batteries (around 220 amp-hr capacity @ 12 VDC).

To give you a good starting point for comparing, most 6 VDC golf cart batteries are around 220 amp-hrs. So you currently have about 440 amp hrs @ 12 VDC. If you discharge to 50% that gives you a max of 220 amp hrs @ 12 VDC available. Add up your electrical needs and see if you can do with less.

Brett Wolfe

[kalynzoo]

Good advice from Wolfe. My rig has 2x12volt plus 12v engine batteries. We seldom, very seldom, dry camp. Perhaps a single overnight with a group, but then most time is spend outside and food is prepared outside, so little power is required. During our Tracks experience in Mexico we went 5 days without hookup, but, the batteries were purchased just before the trip, and we ran the generator for a couple of hours every day, and again we judiciously conserved electric power. Last year we did not do a day without shore power, even when staying at a friends ranch we had 15amps available. Therefore, for us, the cheap deep cell from Costco or Walmart works just fine. I am now 30 months into the 36 month batteries, and it is time for new one. So this spring, before our next trip, I will probably purchase 2 cheap batteries, hopefully less that $100 each, and they will last a couple of years again.

This works for me.

Happy Trails.

[wolfe10]

Good advice from Wolfe. My rig has 2x12 volt plus 12v engine batteries. We seldom, very seldom, dry camp. Perhaps a single overnight with a group, but then most time is spend outside and food is prepared outside, so little power is required. During our Tracks experience in Mexico we went 5 days without hookup, but, the batteries were purchased just before the trip, and we ran the generator for a couple of hours every day, and again we judiciously conserved electric power. Last year we did not do a day without shore power, even when staying at a friends ranch we had 15amps available. Therefore, for us, the cheap deep cell from Costco or Walmart works just fine. I am now 30 months into the 36 month batteries, and it is time for new one. So this spring, before our next trip, I will probably purchase 2 cheap batteries, hopefully less that $100 each, and they will last a couple of years again.

This works for me.

Happy Trails.

And before buying two more 12VDC batteries (VERY hard and expensive to find deep cycle 12 VDC batteries) look into two 6 VDC golf cart batteries that you would install in SERIES instead of PARALLEL-- well under $100 each and true deep cycle batteries. Around 220 amp-hrs @ 12 VDC. Cosco, Sams, Golf cart shops, etc stock them.

Brett Wolfe