House Batteries need replacement

[discus277]

I have 2 yr old coach with (4) 6 volt deep cycle house batteries. Also have 120 volt refrigerator so inverter supplies power. Last winter power got left on and so batteries were fully discharged then below freezing for several days.....I think they are toast....so I only have power if connected to shore power or engine running

I think AGM batteries is what I want....any suggestions as to brand I should get and where?

Also, any concerns about charging....apparently they can be ocercharged. My coach is a Fleetwood Excursion 33 ft diesel pusher.    Has a Magnum inverter.  I am assuming it has an intelligent charger

Any thoughts appreciated

Thanks

 

[John From Detroit]

THe biggest advantage to AGM batteries is the profit the company selling them to you makes.
THey are not DRY but "Starved" and I'm not sure how well they do forzen and discharged. Generally for any rechargable battery a full discharge is not a good thing.

ONE thing may have saved you on your existing batteries (Do not write 'em off till you test 'em)

THe inverter has a low DC voltage shutdown feature.

 

[Gary RV_Wizard]

I'm not negative on AGMs as John is, but they are indeed pricey.  The zero maintenance is really convenient, though. No water to add and no corrosion from venting acidic gases.  They won't hold up any better than those flooded 6v's though, if you let them run down and freeze. It's still a lead-acid battery. If you are willing to pay the price for the AGM convenience, its a solid choice.


Charging them on a standard multi-stage charger is not a problem. Tour Magnum probably has an AGM charging profile that is selectable, but the standard profile is only slightly sub-optimal and should have no significant impact. There are so many factors in RV battery usage that can negatively impact battery life that it's pointless to worry over each little thing.  I got 8 years from a set of Trojan AGMs using a Xantrex inverter/charger and standard charging profile.

 

[Kevin Means]

I'm another fan of AGMs. We didn't have them in our previous two motorhomes, but they are OEM with Winnie Tours, and I'll never go back to standard lead/acid batteries. There are a fair amount of tasks that I perform to maintain our coach, but thankfully, battery servicing is no longer one of them. They're trully maintenance free, and the only thing I do is keep the dust off them and make sure their cables are tight.

We have eight Group 31, 105 AH house batteries, made by East Penn, and I just replaced them six months ago. The original set lasted 7 & 1/2 years, but they were starting to take a bit longer to recharge. We boondock a lot and we rely heavily on our batteries and solar, so I monitor their SOC closely. I don't let them go below 75% SOC and I fully recharge them the next day. I'm convinced that that extends their life.

Like Gary said, they're pretty pricey, but in my opinion, they're worth it.

Kev

 

[Jim Godward]

In 2010 I bought a set of "WaterMizer" caps for my flooded cell batteries.  I replaced the batteries last January due to a problem with my solar system allowing them to completely discharge.  In that time I only needed to check the cells for water every 3 months or so and hose them off about once a year.  The caps cost about <$75 and I am still using them on the new batteries.  Several of my friends have done the same thing and all have been happy with them.  They are a great alternative to the high price of the AGMs in my mind.

Check them out on the internet as a lot of solar systems use them instead of the AGMs.

Just an alternative approach,

 

[Larry N.]

I'm using the Pro-Fill battery watering system. I literally hook a small hand pump to the Pro-Fill, putting the other end in a jug of distilled water, squeeze a few times, and I'm done. It takes less than 10 minutes, including getting out the water jug and pump, and putting them away. Beasts the dickens out of the two to three hours it took in my previous rig without the Pro-Fill.

 

[John From Detroit]

My "New" 4 years ago DEKA G-20's needed water.. For the FIRST TIME.  This spring.

 

[Gary RV_Wizard]

The frequency of replacing the water in a flooded cell battery depends largely on the quality of the charging system, followed by typical ambient temperatures. A decent multi-stage charger won't boil the batteries much.  Frequent deep charging in hot weather can cause a lot of water loss, whereas light use and cooler temps are kind to batteries.

 

[Jim Godward]

The frequency of replacing the water in a flooded cell battery depends largely on the quality of the charging system, followed by typical ambient temperatures. A decent multi-stage charger won't boil the batteries much.  Frequent deep charging in hot weather can cause a lot of water loss, whereas light use and cooler temps are kind to batteries.

Gary has it right and that is what the "WaterMizer" caps do in that they tend to condense the liquid that comes from the charging and recycle it to the cells thus retaining the water longer.  This also prevents the gases from getting into the air and causing the corrosion that normally occurs around batteries thus the clean battery compartment I mentioned.

 

[discus277]

The biggest advantage to AGM batteries is the profit the company selling them to you makes.
They are not DRY but "Starved" and I'm not sure how well they do forzen and discharged. Generally for any rechargable battery a full discharge is not a good thing.

ONE thing may have saved you on your existing batteries (Do not write 'em off till you test 'em)

The inverter has a low DC voltage shutdown feature.

How do I test them? ......When I tried to start the coach last winter after the cold weather the batteries were completely dead...both the house and chassis batteries....got started by attaching charger to engine starter battery overnight....

After looking at prices and reading all your comments I?m inclined to stay with t

 

[billwild]

A 2 year old coach and the batteries are dead. Sounds like another example of not having power to charge batteries or having a solar charger, when parked for a long time. I learned the hard way as well. It would be worth it to install a solar system and probably cheaper in the long run saving on batteries.

 

[A Traveler]

Count me in as another convert to AGM batteries. Buy ?em, install ?em and forget ?em. That convenience and lack of any harmful gasses is worth every penny of the extra money. I, too, would never go back to regular lead-acid batteries.

The charging voltage for AGM?s is slightly different. Your Magnum will have a setting for charging AGM batteries. Dig out the manual and check it out.