Problem House batteries going dry

[thirdtimesacharm]

I searched but couldn’t find anything on this? Got our new to us coach end of June and checked house batteries (wet) and they were dry? Added 6 gallon of distilled water to them checked them today and they are almost dry again? The Magnum energy controller is showing Absorb Charging: 14.3 +103A?

 

[Greg and Mary Brannon]

I have 2 house battery systems that run inverters, one on a boat with 12, 6-volt GC2 golf cart batteries (10 years), the other on an RV with 4 GC2s (2 years), and I've never had to add that much water. Your battery cases are either damaged and leaking - look for signs, or they're being overcharged and boiling dry or nearly dry.

How old are your batteries and how many do you have in the house bank? How long did it take for them to go dry from when you watered them? How are you watering them? Were the batteries dry or refilled when you recorded the 14.3V/103A? Is your battery charging system always plugged in? I'd be curious to know what happens if you leave the charging system off or unplugged. Does the Magnum system have an inverter? If yes, have you ever used the inverter?

I suspect that the batteries need replacing no matter what you learn here. The batteries that were installed on my boat when I bought it lasted 6 years, but there was an overcharging problem throughout their lives. Still, I never had to add more than ~3 quarts to all 12 batteries and there were never plates exposed.

Best of luck! (Start shopping for new batteries.)

Greg.

 

[lostinfla]

I'm so happy I don't have to deal with wet cells anymore. If you had to add that much water, they are most likely toast. Go with AGM or Lithium for replacements. Lithium will save you a lot of weight and turn that dungeon of a battery compartment to a useful storage area.

 

[DennisT]

If the inverter is staying in absorption mode that is not helping. Should be in float normally.

Our Victron goes into absorption for an hour a week and is in float the rest of the time.

I know when we travel the higher voltage going to the house batteries from the alternator causes them to need more water when we stop.

 

[Wemustrv]

Check the configuration on the energy management system to see what the charge settings are. Make sure they are set for wet cell and not Absorption Glass Mat(AGM) or Lithium. Have you tested the batteries? This high of water usage is bad and to me indicates overcharging.

 

[thirdtimesacharm]

Thanks for the responses. I have been reading the manual and haven’t got deep enough into it for the settings? I’m thinking the batteries are cooked! I cannot find a date on them?I’m having a RV tech looking at it next week. Until then I have been turning the charger on and off. Thinking back when I would look at the controller it would be in Absorption mode so I’m thinking about reaching out to Magnum Energy for help. It is an 8 battery bank.

 

[redbaron]

This might help you

Simple Guide to Battery Life in Your RV

This guide explains the 12-volt battery system found in all RV’s and how to properly maintain them. There is specific information relating to Magnum Inverter/Chargers and Newmar motorhomes th…

newmarhoots.com

 

[Joe Hogan]

A summation of Internet knowledge:

12V Battery Water Depletion

A 12V wet acid battery, also known as a flooded lead-acid battery, can run dry quickly due to several factors. One primary reason is excessive heat exposure, which can cause the electrolyte fluid to evaporate, leading to a condition where the battery is "boiled dry" This situation can occur if the battery is not properly maintained, as the electrolyte level needs to be regularly checked and topped up with distilled water to ensure the lead plates remain submerged

Another reason could be improper charging practices. Overcharging can accelerate the rate of water loss through electrolysis, where water is split into hydrogen and oxygen gases, which escape from the battery Additionally, if the battery is not sealed properly, there is a risk of leakage, which can also lead to a rapid loss of electrolyte.

Regular maintenance, including checking the electrolyte level and ensuring proper charging, is essential to prevent a 12V wet acid battery from running dry quickly. If the battery does run dry, it may be possible to repair it by refilling with distilled water and recharging it slowly, but this depends on the extent of sulfation that has occurred on the lead plates

 

[Chuggs]

Well...looks like the perfect storm.

1) too high a charge rate. Interstate recommends C/10. So if you have 880aH bank...it would be 88A --- NOT 103A. Unfortunately, you can't do 88A. You have to enter a percent based on the 125A max of the unit. Set 70% for a while and see how that goes. Next is Absorb Time. Magnum has you set a number of minutes based on Bank size. Sometimes people add aH for all the batteries and come up with a number twice as long. If two batteries are joined in series, you add voltages together, you do not add aH together. If you routinely boondock...and draw your bank down to 50 - 80%...fine. Let them absorb for 3 hrs or whatever the manual prescribes...but if you plug in all the time... you do not need to absorb that long. Maybe half the time. My Victron Charge Controller absorbs about 30 minutes if the SOC was not drained too much. Final Charge, has an impact. And lastly, keep terminals clean...resistance adds heat...and consider mineral oil or "battery demister" to cut down on misting of electrolytes.

Hope you find a pearl in there.