Everything you need to know about house battery maintenance

[mpa24]

My dad is a proud owner of a 2006 Fleetwood Discovery Diesel Pusher, and he's still trying to figure out some of the basics since he doesn't use it much - while it's stored, it is plugged into 50amp shore power. It has four 6V deep cycle house batteries (Interstate). I kept telling him he has to check the water levels, but since all the battery terminal connections were in the way of the vent caps he didn't think he had to check. So new batteries it is! I saw there is a separate thread on here on installation, but i'm still confused on maintenance of the new batteries after talking to some battery folks and reading "The 12 volt side of life" article, so please bear with me on all the questions. My dad thinks some of the stuff i've heard/read is not what most folks really do, so i would really appreciate any feedback.

1) How often do you all really check your water levels - i've heard every 4-6 weeks or every other month. Since my dad is planning on traveling soon for about 6 weeks and it seems pretty hot everywhere, i told him he will need to check on his trip, but he disagrees and says they should be fine?

2) Do you all really go through the hassle of pulling off your battery cables or do you just use a battery watering system? If the latter, do you really leave a bottle of distilled water in the battery compartment for the pump - seems like there would be no room and it wouldn't be good for the water?

3) Was told since the batts were new, they should be cycled 15-20 times (to 50%, i think) by unplugging shore power and running appliances on the batts. Before my dad goes on his trip? Seems like it would be difficult to do 1 cycle since there would be enough power to last a couple of days boondocking? And wouldn't it be difficult to get to 50% normally b/c something would always be charging the batts - like the alternator when driving or the inverter/charger when plugged in?

4) I tried by turning on the Inverter (Xantrex Freedom Inverter/Charger) and running appliances, including the microwave. I read later some folks say doing that is bad for the microwave, so they don't use the inverter? (The Xantrex manual says the inverter provides power to the microwave.)

5) I also noticed the DC volts on the Xantrex turned from green to yellow and lit up only to 11.5V while the appliance was on. Is it okay to look at this reading to see where the state of the house battery bank is (which should not be below 12V for 50%)?

6) My draining efforts barely made a dent. I also noticed somewhere it is not good to leave house batts in a partially used state, so i plugged in shore power and let the inverter/charger do its thing.

7) How often do you equalize your batteries? Heard once a year is good, or checking with a hydrometer for a 10-point spread (usually every 2-3 months).

8) Finally, when the rv is being stored for a while on shore power, should the house battery disconnect switch be engaged to conserve the batt or should the inverter/charger just keep it charged?

Thank you for reading; apologies this turned out to be so long. Kudos to all of you for being so knowledgeable about so many complex things!!

[vsheetz]

We use our MH about once/month plus a couple three trips of a week or two each year. I check batteries before each trip or once a month if no trip. Coach is plugged into shore power all the time and do not use the disconnect switch. No cycling, equilizing, or similar activities.

Batteries are accessible to fill with water so don't have a filling system.

Four 6V Trogen batteries with 3000 watt inverter. Runs the microwave just fine.

Last set of batteries lasted 6+ years (don't know how long the plus is, the batteries came with the coach and don't know how old total). Current set is about 5 years old.

[vraines]

I leave my DP connected to shore power when not in use.
Check the batteries every couple of weeks until you are comfortable with how hard the inverter is on them. Very inexpensive to keep them serviced. I now check every month or so.
Keep the terminals clean and corrosion free. Good products in auto supply stores work well.
Safety first when checking and servicing. No jewelry, good ventilation.
There are some threads on this site for home made servicing kits. Check them out.
They should last more than three years if maintained. My dealer says to expect no more than three years, but my experience has been better than that.
I use Interstate, but have had smarter people than me say there are cheaper batteries that are just as good.
I have not dry camped, but would expect to get several days on a charge if no microwave and refrigerator on gas.
If you change them out, take a cell phone pic of the connections, or make good notes.
Again, lots of amps here. Get the ground disconnected first.
Good luck.

[vraines]

Oh,I have never equalized, and I leave the batteries connected when stored. No cycling required.

[RickO]

Hi and welcome to the forum.

My thoughts are:

1) I check my batteries about once per month. If I skip a month it's not likely to be a problem.

2) Your life will remain very difficult until you remove all of those battery cables, clean them, and then reinstall with them properly dressed and routed around the filler caps. Having to remove the cables to check the water is not acceptable. Watering systems are very nice to have. I don't believe folks keep a jug of water always attached to the system but rather attach one when checking water levels and then remove and stow it.

3) I've never heard of cycling new batteries 15/20 times.

4) I'm really surprised that your microwave is powered by the inverter and would be cautious when using it in that mode.

7) I don't equalized my batteries. I believe my inverter "conditions" them about every 10th cycle or so but it's done automatically.

8) When connected to shore power during storage, I wouldn't disconnect the batteries but rather let your inverter manage them. Just be sure to check water levels monthly.

Best of luck

Rick

[Triker56]

Originally Posted by mpa24

1) How often do you all really check your water levels - i've heard every 4-6 weeks or every other month. Since my dad is planning on traveling soon for about 6 weeks and it seems pretty hot everywhere, i told him he will need to check on his trip, but he disagrees and says they should be fine?
I check the water in mine every 45 days and have a reminder on my PC calendar.

2) Do you all really go through the hassle of pulling off your battery cables or do you just use a battery watering system? If the latter, do you really leave a bottle of distilled water in the battery compartment for the pump - seems like there would be no room and it wouldn't be good for the water?
I use Flow-rite RV Battery filling systems, Quick Fill, Qwikfill, profill, pro-fill, battery water level Camping World - Flow-rite RV Battery filling systems, Quick Fill, Qwikfill, profill, pro-fill, battery water level - Product - Camping World to fill mine in less then 5 minutes. Keep a gal of distilled water in another compartment Also use it if needed for radiator 50/50 mix.

3) Was told since the batts were new, they should be cycled 15-20 times (to 50%, i think) by unplugging shore power and running appliances on the batts. Before my dad goes on his trip? Seems like it would be difficult to do 1 cycle since there would be enough power to last a couple of days boondocking? And wouldn't it be difficult to get to 50% normally b/c something would always be charging the batts - like the alternator when driving or the inverter/charger when plugged in?
They don't need cycled as each cycle shortens the life of them.

4) I tried by turning on the Inverter (Xantrex Freedom Inverter/Charger) and running appliances, including the microwave. I read later some folks say doing that is bad for the microwave, so they don't use the inverter? (The Xantrex manual says the inverter provides power to the microwave.)
On some Discovery's the inverter is the only feed for the Microwave/Convection. And there have been no reported damage from it doing so.


5) I also noticed the DC volts on the Xantrex turned from green to yellow and lit up only to 11.5V while the appliance was on. Is it okay to look at this reading to see where the state of the house battery bank is (which should not be below 12V for 50%)?
The Yellow light means the battery bank is receiving a charge from the Inverter/Charger and is Normal.

6) My draining efforts barely made a dent. I also noticed somewhere it is not good to leave house batts in a partially used state, so i plugged in shore power and let the inverter/charger do its thing.

7) How often do you equalize your batteries? Heard once a year is good, or checking with a hydrometer for a 10-point spread (usually every 2-3 months).
My D's batteries are now 7 years old and they have never been equalized. I am plugged in to shore power 24/7.

8) Finally, when the rv is being stored for a while on shore power, should the house battery disconnect switch be engaged to conserve the batt or should the inverter/charger just keep it charged?
If it is plugged in. Never turn house or chassis switch off. And check water in house batteries every40-45 days

Thank you for reading; apologies this turned out to be so long. Kudos to all of you for being so knowledgeable about so many complex things!!

For a lot more info for a Discovery and support.
Check out DOAI MAIN PAGE

[Gary RVRoamer]

1) How often do you all really check your water levels - i've heard every 4-6 weeks or every other month. Since my dad is planning on traveling soon for about 6 weeks and it seems pretty hot everywhere, i told him he will need to check on his trip, but he disagrees and says they should be fine?

Best to check monthly until a usage pattern is established. With a quality inverter/charger, he probably won't have to add water that often, but until you know for sure how fast the water evaporates, it is best to check often.

2) Do you all really go through the hassle of pulling off your battery cables or do you just use a battery watering system? If the latter, do you really leave a bottle of distilled water in the battery compartment for the pump - seems like there would be no room and it wouldn't be good for the water?

You should NOT have to pull off wires to check water. Need to do some re-routing. Or add one of those watering systems if that is not practical. Just keep a jug of distilled water somewhere in the coach - does not have to stay connected.

3) Was told since the batts were new, they should be cycled 15-20 times (to 50%, i think) by unplugging shore power and running appliances on the batts. Before my dad goes on his trip? Seems like it would be difficult to do 1 cycle since there would be enough power to last a couple of days boondocking? And wouldn't it be difficult to get to 50% normally b/c something would always be charging the batts - like the alternator when driving or the inverter/charger when plugged in?

I've heard that mentioned recently for the very first time. Seems improbable to me. Lead acid batteries don't need to be conditioned like that.

4) I tried by turning on the Inverter (Xantrex Freedom Inverter/Charger) and running appliances, including the microwave. I read later some folks say doing that is bad for the microwave, so they don't use the inverter? (The Xantrex manual says the inverter provides power to the microwave.)

Pure hogwash. Running the microwave and other appliances is one of the reasons to have an inverter in the first place.

5) I also noticed the DC volts on the Xantrex turned from green to yellow and lit up only to 11.5V while the appliance was on. Is it okay to look at this reading to see where the state of the house battery bank is (which should not be below 12V for 50%)?

Sure, use the voltage display. That's what its there for. But remember that the volatge will be low wheile the inverter is drawing power. A soon as the load stops, e.g. microwave shuts off, the voltage will bounce back up again. The 50% discharge level is measured with the battery at rest, not under load.

6) My draining efforts barely made a dent. I also noticed somewhere it is not good to leave house batts in a partially used state, so i plugged in shore power and let the inverter/charger do its thing.

Right.

7) How often do you equalize your batteries? Heard once a year is good, or checking with a hydrometer for a 10-point spread (usually every 2-3 months).

I don't bother equalizing (I have AGM batteries), but if you choose to do that, your method is as good as any.

8) Finally, when the rv is being stored for a while on shore power, should the house battery disconnect switch be engaged to conserve the batt or should the inverter/charger just keep it charged?

If plugged to shore power, leave the disconnect in the On position (batteries "live"). No need to disconnect when shore power is available and in fact that might even stop the inverter from charging them (depends on the design of the electrical system).

[mpa24]

Lots of great input and clarification! Thank you for helping me understand better. Hmm, guess my dad was right - the whole thing is not supposed to be so complicated (with the cycling and equalizing, etc).

My dad tried to clear the vent caps during his install of the batteries, but the fit is kind of tight. Last time he had Camping World install the batteries & they ran the cables over the caps, so now he knows better. I also now see i misunderstood the "automatically sends water to low cells only" for the battery watering system - thought the system & pump filled automatically, hence the confusion about the water bottle placement.

[Muddypaws]

When I changed from Interstate to Kirkland 6V batteries I had the same problem with not being able to get the caps off due to the routing of the wires. Re-routing the wires was out of the question so I got 8 of these

Battery Doctor/Brass extender with nut for top post batteries (30600) | Battery Terminal End and Adapter | AutoZone.com_

to raise the wires up off the caps.

As far as adding water to the batteries goes I use a battery filler, but a bicyclist water bottle will work. I've seen people use turkey basters with success too. Distlled water only. If you're unsure how much water to put in get the battery filler.

If the tops of the batteries are dirty it's OK to spray them off with water, being careful not to spray it directly on the caps to much. Then let it dry before you remove the caps. Anyting that gets in the batteries that isn't distilled water is generally bad for them.

[Cat320]

A lot of this discussion concerns checking the water, moving cables, charging issues, etc. Those problems can be solved by getting Absorbed Glass Mat (AGM) batteries.

They don't leak, don't freeze, don't require any maintenance and can sit along time without recharging. The down side is that they are expensive.

AGM Battery | AGM Batteries | AGM Deep Cycle Batteries

[Jack1234]

Originally Posted by Cat320

A lot of this discussion concerns checking the water, moving cables, charging issues, etc. Those problems can be solved by getting Absorbed Glass Mat (AGM) batteries.

They don't leak, don't freeze, don't require any maintenance and can sit along time without recharging. The down side is that they are expensive.

AGM Battery | AGM Batteries | AGM Deep Cycle Batteries

You are so right....but at about 3x more expensive, I "wish" I could justify the $$$$$. Wishing just won't work for me, so the small amount of work to insure my charger is properly set-up, my cables are clean, my caps are unobstructed and the water levels managed, will have to do....besides more $$$$ for golf!

[justaroamer]

"Every Thing You Need to Know About House Battery Maintenance" ...Simple get AGM Batteries and ForGget auBoutit!
I agree totally with the previous 2 posts...AGM is the only way to go, have 11 of them, house (8) and chassis(3)...never need to do filling, etc. and don't have the "white battery mold" from constant outgassing as wet batteries do.
At an approximate cost of $2k for all, that is only $400 per year over a 5 year life span.
Yes the AGM's should and will outlast the wets, as they have a better life cycle and more deep cycle rating. Much of the outgassing comes from one bad cell/battery in the bank that will charge and "boil" the stronger cells/batteries, which leads to maintenance and which with the lack there of, shortens the life of the entire bank. AGMs charge to 100%, where wets only charge fully to 80% (to avoid outgassing/boiling). There is a reason that one needs to set the charging mode on your convertor/charger control panel as it needs to know what batteries it is dealing with.
If one worries with battery price, then one probably worries with fuel mileage...get out there and enjoy...
Life is better with AGM's.

[clyon51]

I really have nothing against AGMs and I understand why people like them. However, their cost is prohibitive for many especially when you compare Amp Hours vs $ and longevity. With a good smart charger like the Progressive Dynamics 9200 Series and some good Trojans or Interstate 6V CG batteries, they last 10 years. IE, I'm almost at 1 year with my new setup and have yet to add water to my Trojans and my coach is plugged in 24/7. I doubt you will find any serious boondocker who uses AGMs since they don't really compare in storage capacity.

On the other hand, if you just bop from campground to campground there's no real concern. AGMs are great for folks who want to add extra batteries, but have to put them in living space, along with those that don't have 30 mins a year to check their flooded cells It really boils down to the money you want to spend, what kind of RVing you do or, if you like to tinker or just drive and camp. As always, to each his own

[justaroamer]

Originally Posted by clyon51

I really have nothing against AGMs and I understand why people like them. However, their cost is prohibitive for many especially when you compare Amp Hours vs $ and longevity. With a good smart charger like the Progressive Dynamics 9200 Series and some good Trojans or Interstate 6V CG batteries, they last 10 years. IE, I'm almost at 1 year with my new setup and have yet to add water to my Trojans and my coach is plugged in 24/7. I doubt you will find any serious boondocker who uses AGMs since they don't really compare in storage capacity.

On the other hand, if you just bop from campground to campground there's no real concern. AGMs are great for folks who want to add extra batteries, but have to put them in living space, along with those that don't have 30 mins a year to check their flooded cells It really boils down to the money you want to spend, what kind of RVing you do or, if you like to tinker or just drive and camp. As always, to each his own

Ughhh... "AGMs since they don't really compare in storage capacity." You might want to check this a bit more.
Are the electric cars/hybrids using GC wet batteries? Wet batteries is a technology that is centuries old...time to change, many do. Cost is comming down on AGMs and I might mention that the capacity of a wet is at 100% and they only charge to 80%, where as AGMs are rated and charged to 100%. Do the math.
No offense and with all due respect....do you tow the Dolphin with the Super Duty or is the Super Duty your Toad???