confused about my RV house batteries

I think it is important to know when the state of charge approaches the dreaded 50% where damage begins. The voltage method doesn't work until at least 8 hours after all charging has ceased. Measuring acid density is awkward. It seems to me the only practical method is a battery monitor that keeps track of the amp-hours of charge in the batteries. Even a cheap one is a big help.

classctioga73 wrote:
pnichols
whats the brand and make of the true deep cycle batteries you have in your coach. could yo possible give me the dimensions to see if they would fit in my battery storage compartment.

I'm have a couple these under the entrance step in our Itasca's battery compartment wired in parallel with each other. I use (large guage) double cables between their positive terminals and between their negative terminals just to make sure that there is never any voltage difference between them, as I want them to function as close as possibe as one large battery:

http://www.fullriverbattery.com/product/batteries/DC115-12

Here's some comments about these batteries and how I use them:

1. They aren't inexpensive ... but you get what you pay for (sometimes).

2. My last set of two AGM batteries in our Class C lasted around 8 years and weren't completely bad by any stretch, even then, when I took them out.

3. They require no maintenance other than dusting them off so that they keep their pretty blue color.

4. Their recommended float voltage is 13.6 volts, so I just keep them hooked up to our RV's stock single stage 13.6 volt converter all the time and it doesn't shorten their life at all.

5. AGM dry (suspended acid) batteries charge faster than liquid acid batteries for any given voltage you apply to them, so my AGM batteries get both floated and charged (fast enough for our camping style) on the same stock single stage 13.6 volt RV converter. I don't see any need to spend another $150-$200 just to replace our perfectly good stock converter - since these batteries do just fine with the stock 7345 Parallax converter that came in the RV.

6. These two batteries of couse get hit with greater than 14 volts from the engine alternator whenever were traveling, so they do occasionally see more volts than 13.6 from the converter.

7. They have no fumes, so they could be kept inside an RV's living area if needed.

8. I have them permanently wired to both an ammeter and a voltmerter that are Velcro'd onto the cab dash so that I know what their condition is at all times - even when going down the road because then the voltmeter will jump up to 14.XX volts - showing that they are getting properly charged from the alternator. (I have had this reading be too low at times when driving - which has been an advance warning of a serious trip-impacting problem that has occured twice in 10 years of owning our RV.)

pnichols
whats the brand and make of the true deep cycle batteries you have in your coach. could yo possible give me the dimensions to see if they would fit in my battery storage compartment.

It got down to 45 degrees the first night then about 50-55 the last nights we were there. My wife thinks she has all the luxury as home. I bundled up with sweat pants and hoodie sweater, she was in nightgown and no socks. We camped at manzanita lake campgrounds
I think it was partially that we were not allowed to run the generator longer than 2 hours a time, I didn't get sufficient recharge time off the generator to charge the batteries
I'm either going with two six volts or two 27 or 31 series 12 volt batteries

I just ordered all new led bulbs off the internet, very inexpensive and very affordable

How cold was it at Lassen N.P.?

We have two Group 31 12 volt true deep cycle batteries under our entrance step (that gives us 230 amp-hours of stored capacity). We keep our propane furnace set at 62 degrees at night and in about 38 degree outside temperatures the furnace is NOT on continuoulsy - it cycles ON/OFF all night so it's not using the batteries full time at all.

Our 230 amp-hours of battery storage can keep us going 2-3 days without recharging if the furnace is used only at night. We also have a couple of CPAP machines running off the batteries at night. However, using the furnace 24/7 would be another story. Our Class C is only a 24 footer, so your rig may require a lot more furnace run-time during the night .... but even so, two Group 31 12 volt true deep cycle (NOT marine/RV) batteries should be adequate for your needs if properly taken care of.

Our batteries do not give off any fumes, so it you used the same kind you could safely have a couple more of them (for a total in your rig of 4) inside your coach so that you wouldn't have to do any venting of them to the outside for removal of fumes. Personally, I'd never have regular batteries with liquid acid in them inside a living environment, vented or otherwise. Our batteries do not have liquid acid in them, as they are dry (AGM) batteries ... they cost a bit more but require no maintenance whatsoever and are free of fumes.

Modern converter chargers have quicker recharge and maintenance modes but will not recharge a discharged house battery in a few hours. The engine's alternator charges the house battery(s) more quickly while driving some distance, but running the engine for an hour won't do much. How long recharging takes will vary with the converter charger, condition of batteries, and amount of miles/driving time. Stock house battery setups will usually power interior lights and appliance controls for up to 3 days without running the furnace blower. RV's are designed to work on shore power in RV parks, not set up/equipped for off grid camping.

classctioga73 wrote:
cgmartine
What's the recharge time on the 6 volt batteries?
Would they charge off the generator?
I've been hearing a lot of good things about 6 volt but also that they take longer to recharge
Would I need to upgrade my converter?

It is TWO 6v batteries in series, to make one big 12v battery. You do not need to do anything to your converter (unless it is single stage and you want to upgrade to a three stage) and yes, they charge off the generator (as it simply powers the converter) and also will charge off the chassis system if it is so wired now. Yes, they are larger capacity, thus can take longer to recharge if you discharge them very low.

Charles

cgmartine
What's the recharge time on the 6 volt batteries?
Would they charge off the generator?
I've been hearing a lot of good things about 6 volt but also that they take longer to recharge
Would I need to upgrade my converter?

Yours might be different. Look for the closest spot that two 6v will fit. Keep in mind it's OK inside but you need to vent it outside.
Think using a plastic box. They have them all sizes. Mount the box, strap it to the floor etc. Use biiig cables. Any other questions?
Bob

There is a upholstered chair inside the door pass side. Behind that chair I mounted two 6v gc batts in a plastic box end to end. Two big cables to two more 6v gc batts under the stairs. I got a vent kit off the internet. Drilled a two inch hole in the wall for vent. Four is all you need. I have 550w of solar and a 2000w psw
inverter because I plan on installing a residential fridge when
my dometic dies.