Follow-up to 12-volt roof air and refrigerator question. What are the best batteries?

Dear Dave,
I know you have probably covered this but I can’t locate info on the best lead acid batteries for RV life. Can you direct me to the location? —Alicia, 1989 Winnebago Warrior

[The original question from Alicia and post covered replacing the standard air conditioner and refrigerator with 12-volt models. After sending her the rough draft, I got some additional information:]

Dave,
I see I didn’t give you all the info… We have the Class A model with the 454 motor. All original except for the A/C unit. One battery for the truck and two for the RV—lead acid.

We’re not really planning on boondocking, just trying to become more efficient and quieter.

We are pulling the ginormous propane tank (space to add more batteries when we add a floor) and the boat anchor of a Onan generator. We have removed the cooktop/oven and replaced it with more storage and purchased a Duxtop induction 2 burner unit. There is now a lovely teak countertop in place of the old propane burners. The microwave will be upgraded, as well, as it is the original with the dial.

The generator replacement we are still shopping for (maybe a Firman Inverter 3650W), but maybe we can find something to fit in the Onan space or mount it to the bumper. (Firman has a remote.) As of now you have to go outside, plug in the shore power cord to the generator then start it! The plug is in the cubby where you coil the power cord for travel…things were way different in “89”!

We are ready to install the Dometic 4101. Looks like a good fit and we made the space way more sturdy. We will add trim to the sides and have the blessing of the door opening enough to move shelves as needed.

The OutEquipPro [air conditioner], which we will buy directly from OEP, is still on the table as 8 holes will need to be drilled in the roof (kinda yikes). But I believe we will go with it due to the less power needed and the quietness. They have been very quick to return responses to my questions. The one we have now is a newer unit, Coleman-Mach 48000 Series 115volt, but still runs at 75db. Even on low you cannot have a conversation. Why have they not addressed this with ductless models? There has been 12v A/C’s in automobiles since the 60’s!

Off topic…We have a U-shaped window unit (Midea) in the shop and you can barely hear it on full. The OEP Glacier Pro on full is 60db.

So that is it for now. This is our first complete redo for an RV. Previously we have done remodeling on other units for maximizing storage but not a complete appliance RnR.

I am so glad I came across this magazine. It is very enlightening, entertaining and in some cases lifesaving!

Looking forward,
Ali

Back to her current question

Dear Alicia,
Thanks for the follow-up information and the opportunity to address flooded lead acid (FLA) batteries.

You are upgrading quite a few features to use 12-volt power. The FLA batteries should only be drained to 50% State Of Charge (SOC), so, if you change your mind and decide to do some boondocking, you would not be able to do it and run everything!

The first thing I would suggest is to take a look at your converter, which is the device that will provide the 12-volt power when connected to shoreline power. Your unit most likely has the all-in-one distribution center that has a very small amp converter, which would be  insufficient to power all the new “stuff”. This is a photo of the one from our 1996 Salem trailer with the converter on the bottom. I believe it was only 30 amp and was not very efficient.

I would suggest contacting Progressive Dynamics and upgrade and get a higher amp model, as well as the more efficient and quieter digital models. You can get one that slides into the lower opening; however, it does require a new fuse board and control module. We found it was just easier to get a new stand-alone model like this one.

If you plan to use FLA batteries, I suggest NAPA, as they are very durable and what Winnebago uses now. They have top-quality lead plates, connections, and other materials. They will last longer, and if you get a Progressive Dynamics converter, will not sulfate as much or as fast.

If you do have to survive even one night without power, you will need to make sure you get enough amp hours to supply everything. However, if you do add the generator/inverter, you can use that if it’s big enough to handle the load.

Calculate the energy draw from the new appliance you are installing and take a look at what battery power you will need. If you definitely are not boondocking much at all, then you can go with a cheaper battery such as Interstate, or even a discount store, as the converter will provide the power if you get the right model.

 You might also enjoy these posts from Dave 

• Can different type and age RV batteries be mixed? Can I add a lithium battery?
• Will RV’s house batteries ‘play nice together’ if I replace chassis battery with lithium?
• Understanding everything about 12-volt house batteries
• What is best brand of FLA batteries for RV? How do I add water to them in a tight compartment?
• My RV’s 6-volt FLA batteries are dry, but service manager says they should be good

DAVE HAS ANSWERED MORE THAN 1,000 readers’ maintenance and repair questions. Read a directory here. There is so much to learn!

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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