Community Forums

av8tor2 · 11-08-2019, 11:45 AM

Quote:

Originally Posted by MSHappyCampers

We keep our coach plugged into 30A service when at home. I have tried to check the batteries occasionally and top them off with distilled water. Well, occasionally wasn't good enough! Yesterday I checked and I couldn't see any water at all! It took 2 1/2 gallons to fill them!

From this point forward I will be checking them when I do the monthly 30-minuted exercise drive!

You are not alone. I checked mine on June 1, and again on Aug. 1. They were totally dry. Added water, they died a week later, started to bulge and out-gas. They are out, awaiting replacement with AGM's. Can't believe they went dry that quick.

richard5933 · 11-08-2019, 12:25 PM

Quote:

Originally Posted by av8tor2

You are not alone. I checked mine on June 1, and again on Aug. 1. They were totally dry. Added water, they died a week later, started to bulge and out-gas. They are out, awaiting replacement with AGM's. Can't believe they went dry that quick.

You need to check the voltage of your charger/charging system. The only way they could go through that much water that quickly is if they are charging at too high a voltage.

Once the batteries are fully charged, the charger should reduce the voltage to around 13.2v for flooded cell batteries. This is a maintenance charge, and charging at this voltage level will greatly reduce the water use.

Even if you replace your batteries with AGM batteries, charging at too high a voltage can and will still do damage.

Most smart chargers will start at about 14.5v for the first few hours, then reduce to somewhere around 13.6v until the batteries are nearly fully charged. At that point the charger should go to a maintenance/storage voltage of around 13.2v (these are all for flooded cell - things may very for AGM so check your particular specs).

Many people think that their little trickle chargers are fine to leave on all the time because they only have 2 or 5 amps output. The amps will not destroy a battery, but if the voltage is too high damage will be done.

Ray,IN · 11-08-2019, 09:10 PM

Quote:

Originally Posted by richard5933

You need to check the voltage of your charger/charging system. The only way they could go through that much water that quickly is if they are charging at too high a voltage.

Once the batteries are fully charged, the charger should reduce the voltage to around 13.2v for flooded cell batteries. This is a maintenance charge, and charging at this voltage level will greatly reduce the water use.

Even if you replace your batteries with AGM batteries, charging at too high a voltage can and will still do damage.

Most smart chargers will start at about 14.5v for the first few hours, then reduce to somewhere around 13.6v until the batteries are nearly fully charged. At that point the charger should go to a maintenance/storage voltage of around 13.2v (these are all for flooded cell - things may very for AGM so check your particular specs).

Many people think that their little trickle chargers are fine to leave on all the time because they only have 2 or 5 amps output. The amps will not destroy a battery, but if the voltage is too high damage will be done.

Can't trust the inverter/charger readout, mine shows float at 14V, checked batteries with my Beckman meter and got a 13.4 reading @ 56°. Exide says my SLA battery model (31XPD) should float at 13.8V.That's too high IMO,but I'm not an expert.

richard5933 · 11-09-2019, 07:09 AM

Quote:

Originally Posted by Ray,IN

Can't trust the inverter/charger readout, mine shows float at 14V, checked batteries with my Beckman meter and got a 13.4 reading @ 56°. Exide says my SLA battery model (31XPD) should float at 13.8V.That's too high IMO,but I'm not an expert.

Good point. A working multi-meter is a must for every RV tool box so readings like this can be verified.

That said, if your inverter/charger is showing 14v and you measure only 13.4v, then possibly you have a voltage loss that needs to be addressed. Have you verified the voltage at the inverter/charger output? Would only take one or two dirty/corroded/loose connections to drop voltage like that. Or possibly just a single bad ground connection.

av8tor2 · 11-09-2019, 12:57 PM

Quote:

Originally Posted by richard5933

You need to check the voltage of your charger/charging system. The only way they could go through that much water that quickly is if they are charging at too high a voltage.

Once the batteries are fully charged, the charger should reduce the voltage to around 13.2v for flooded cell batteries. This is a maintenance charge, and charging at this voltage level will greatly reduce the water use.

Even if you replace your batteries with AGM batteries, charging at too high a voltage can and will still do damage.

Most smart chargers will start at about 14.5v for the first few hours, then reduce to somewhere around 13.6v until the batteries are nearly fully charged. At that point the charger should go to a maintenance/storage voltage of around 13.2v (these are all for flooded cell - things may very for AGM so check your particular specs).

Many people think that their little trickle chargers are fine to leave on all the time because they only have 2 or 5 amps output. The amps will not destroy a battery, but if the voltage is too high damage will be done.

Installed the new batteries. Charge rate shows within specs for the AGMs. And, the new DuraCell AGMs come with 18mo. non-prorated warrenty, so I should be good. Also, it was over 100 here, for over three months, lots of days over 110, maybe that's where the liquid went? I guess, we'll see.

96 Wideglide · 11-09-2019, 01:19 PM

Quote:

Originally Posted by Ray,IN

Can't trust the inverter/charger readout, mine shows float at 14V, checked batteries with my Beckman meter and got a 13.4 reading @ 56°. Exide says my SLA battery model (31XPD) should float at 13.8V.That's too high IMO,but I'm not an expert.

If your inverter/ charger has a battery temp monitor, it will increase charging voltage when the weather gets cooler. I'll often see 13.9V float charge with my Magnum charger.

Ray,IN · 11-10-2019, 10:41 AM

Quote:

Originally Posted by 96 Wideglide

If your inverter/ charger has a battery temp monitor, it will increase charging voltage when the weather gets cooler. I'll often see 13.9V float charge with my Magnum charger.

A said, trmp monitor read 56 atop battery - MH in garage outside temp was 43.
I saw the same float voltage with previous batteries too. These batteries are 5 yrs old, just had to add water 3 days once, the day of that reading.
i'll run an equalize tomorrow, it will be 23 and rain/ice/snow anyway,great time to fiddle with MH in the garage.