house batteries OK?

[RRodda]

Four 6 volt house batteries, topped with distilled water as needed, then plugged in RV overnight. Let is sit 2 days and got the following readings:

Voltages 6.25 to 6.31, set of 4 at 12.58
According to the Trojan chart that is 83 to 90% per battery and 87% for the bank.

Is a load test still needed? Should I take specific gravity readings?

Batteries are Interstate U2200 and are 5 years old, we dry camp extensively.

[pianotuna]

Hi Bob,

Get a better SG unit, one with a float and with temperature compensation.

That said the one battery sounds as if it is in trouble.

[cbr46]

I have 2 cells in one 6V battery with poor SG (all balls don't float). This is after resting for a day. Batteries might be original (13 years old). I was planning to replace them in the fall . . . .

Does the on-board charger (whatever Fleetwood provided in 2002) have an automatic equalization mode? Typically I DON'T leave the RV plugged to 120VAC.

They do seem to hold charge longer if RV is left plugged in but I didn't want to overcharge them or run over the cord with the lawn mower . . . . .

Should I plug in and forget?
(checking water occasionally)

Best,
- bob

[pianotuna]

Hi,

Charge them for another 2 days then let them sit for 12 hours before reading the voltages.

A good temperature compensated specific gravity device is a much more reliable indication of state of charge than voltage.

[wolfe10]

Good idea to occasionally check SG-- that will tell you if you have a cell getting weak and would be a good indicator of when to EQUALIZE.

[korbe]

My 7 yr old Trojans read 6.39 after a recharge.

[2oldman]

I wouldn't bother with those tests. Put a load on them and see how they do. 5 years is getting up there.