Need new power converter?

Whatever charger/converter be sure it is `smart' and does not overcharge the batteries.

Boon Docker wrote:
Short answer, your converter will do just fine with two group 31 batteries. And yes, you assume correctly, the power converter is a battery charger.

"Fine" is relative - if the OP's trailer is equipped with a ubiquitous WFCO 8900 series converter chances are it will never go into bulk charging mode even though it is rated to do so @ 14.4 volts. I've owned several, including the 8955 in my current Coachmen, and I've never seen any of them actually go into bulk mode regardless of the battery SOC. With a substantial investment in dual G31s the OP may well want to switch out his converter to another than will correctly maintain them. ;)

ON EDIT:

I'm in a situation similar to the OP's ... I have a single G27 Interstate that's now 8 yrs old and although it still takes a full charge it's coming time to replace it. Since I added a 1000 watt PSW inverter to the trailer last year to power a few select 120 vac devices (hair dryer, toaster, coffee machine, fans, etc) at times when we may lose campsite power upgrading to a pair of batteries seems like the logical choice. However, the problem then is investing so much in a pair of batteries when the converter I own isn't capable of properly maintaining them. At the moment I'm reorganizing the trailer's A frame and have decided for the interim to just stick with my current G27 as I'm not prepared to sink so much into a new pair of batteries when I know my current WFCO converter is so inadequate.

Will you be charging with a generator? Is that a WFCO converter?

Beware WFCO frequently just trickle charges at 13.6 volts regardless of the sticker that says '3 stage charging'. Yes 55 amps is plenty big for six batteries but you need the 14.4v boost mode to get a decent charge in 2 hours instead of 10.

Your converter is rated to feed the wires coming out of it to the battery. Two batteries will double your capacity, but they will also take twice as long as one to charge.

I have a tiny voltage meter in my rig that tells me my battery voltage, so I can easily see how much I have used, and also how much I have left. After a while just looking at the voltage meter, I get used to understanding how long to charge to bring my voltage up to the desired level. I don't charge to the top with a generator, I only charge until I know I will have enough to go until I charge again.

Short answer, your converter will do just fine with two group 31 batteries. And yes, you assume correctly, the power converter is a battery charger.