Question How to figure out which battery I need?

[Rosy]

I suspect this is probably a stupid question but I need a new battery and I'm not sure how to figure out what size/rating I need. This is for my 2018 Coachmen Freedom Express 25SE. I looked through all the paper manuals I have and also went to the Coachmen website and looked through the manual they have on there for my trailer but didn't find any battery specs. Is there a way to confirm which battery is supposed to be in the trailer or do I just have to assume that the one the previous owners had in there when they sold it to us is right and buy something equivalent?

 

[A-Texan]

I typically assume its correct, and then put what I would like to have in it when replacing one. For example mine came with a 24 series battery that only had 47 amp hours (baby battery), so I upgraded to a 105 amp hour battery when replacing it, this did require me replacing the battery box too that it sits in, but it was pretty easy to do so, the box is just held in with a couple of self-tapping screws in the base of it (deep cycle flooded battery).

Considering that is a pretty good size trailer, I can't imagine it would have anything smaller than 105 amp hour on it, do you know what series it currently has installed, and is there one or two batteries?

 

[Rosy]

I typically assume its correct, and then put what I would like to have in it when replacing one. For example mine came with a 24 series battery that only had 47 amp hours (baby battery), so I upgraded to a 105 amp hour battery when replacing it, this did require me replacing the battery box too that it sits in, but it was pretty easy to do so, the box is just held in with a couple of self-tapping screws in the base of it (deep cycle flooded battery).

Considering that is a pretty good size trailer, I can't imagine it would have anything smaller than 105 amp hour on it, do you know what series it currently has installed, and is there one or two batteries?

It's only wired for one battery right now. I don't really think I need a second since we pretty much only camp (with the trailer) in full service sites and I'm pushing up against the payload capacity of my truck.

Here are the numbers on the battery that was in there. I guess that must say 80 amp hours?

 

[A-Texan]

Well 80 amp hour sounds decent, that is a lot larger than the one that came in my trailer so its probably the right size, especially if you are plugged into shore power most of the time, That's what I would replace it with if it were me. The only reason I upgraded is because on long trips I run our 12v fridge and we needed the extra power for dry camping without electricity, otherwise I would have stayed with the small one I had too.

 

[TheLooks]

The main reason for a battery besides being without plug in power, is to provide the working amps to run things. The convertors can run everything but when amp draw is large a good strong fully charged battery makes sure the current and voltage stay within correct ranges. Furnaces and slide motors are the real hogs. Most times it is the dealers that put the battery in and they cheap out on it to save a nickel. It would not hurt one bit to have more capacity, but can hurt to have to little. Having said all that, it depends on your potential loads and how it has worked for you with the current battery.

 

[Rich W.]

The main reason for a battery besides being without plug in power, is to provide the working amps to run things. The convertors can run everything but when amp draw is large a good strong fully charged battery makes sure the current and voltage stay within correct ranges. Furnaces and slide motors are the real hogs. Most times it is the dealers that put the battery in and they cheap out on it to save a nickel. It would not hurt one bit to have more capacity, but can hurt to have to little. Having said all that, it depends on your potential loads and how it has worked for you with the current battery.

Agree and my rule of thumb for this is to use the battery of greatest capacity that will fit in the box. This might end up being 5-10lbs more but that is negligible compared to having sufficient power to run everything efficiently.

 

[Rosy]

The main reason for a battery besides being without plug in power, is to provide the working amps to run things. The convertors can run everything but when amp draw is large a good strong fully charged battery makes sure the current and voltage stay within correct ranges. Furnaces and slide motors are the real hogs. Most times it is the dealers that put the battery in and they cheap out on it to save a nickel. It would not hurt one bit to have more capacity, but can hurt to have to little. Having said all that, it depends on your potential loads and how it has worked for you with the current battery.

Good points. It's hard to say because I think this battery was probably weak when we bought the trailer. I'm not sure how well the previous owners took care of it. I noticed on our first trip that the converter was running for quite a long time after we finished getting set up. I'll talk to the folks at Battery World and see what they recommend.

 

[TheLooks]

If you could get a look at your convertor it is rated for x amount of amps. Most I have dealt with are 45 to 55 or 65 amps. Larger campers and motorhomes have larger ones I am sure. I would trust the original design not what the dealer put in. The battery box also came from the dealer so it does not indicate what is needed. Personally, I have a 26 ft TT with no slides and I have a 27 series battery rated at 122 amp/hrs. I also removed a 24 series and upgraded. You know that even the original design was right at the edge of what they could get away with so a little extra omph with the battery can't hurt.

 

[Rosy]

If you could get a look at your convertor it is rated for x amount of amps. Most I have dealt with are 45 to 55 or 65 amps. Larger campers and motorhomes have larger ones I am sure. I would trust the original design not what the dealer put in. The battery box also came from the dealer so it does not indicate what is needed. Personally, I have a 26 ft TT with no slides and I have a 27 series battery rated at 122 amp/hrs. I also removed a 24 series and upgraded. You know that even the original design was right at the edge of what they could get away with so a little extra omph with the battery can't hurt.

No specs in my converter manual. I'll have to see if there's anything on the converter itself next time I'm at the trailer.

 

[B52Bombardier1]

Simply replace the plastic battery box with the largest box that the battery store has that will fit the location of the box inside your RV - some measurements required. Then buy the largest amp-hour 12 volt battery possible that has the battery terminals of the style and arrangement that you need for your RV cables.

This took two trips to the battery store for me but it was worth it - I got a very large diesel truck 12 volt battery that I could adapt my travel trailer wiring to - new and different connections required for me. And now this battery is treated kindly all the time by being on a set of two Harbor Freight solar panels (of 4 from their kit) when my trailer is not in use.

And all four panels together are very helpful on even a cloudy day to keep this battery topped off when camping with no commercial power.

Rick