Batteries and more batteries?

[Choxnpinz]

I apologize if this has been addressed in the past. I did a forum search and was inundated with hits, but none matched my situation. It's a rookie question, actually.


2018 Thor Chateau 31W Class-C. During the first year, it was in and out of the dealer repeatedly, and each time they left the house battery switch on, so invariably, they'd be dead as a door nail when I picked it up.



The two house batteries will only keep the residential fridge going for 10-hours before kicking the inverter offline. Other owners tell me it should be a lot more, even without solar.


I'm thinking of replacing the two 12v batteries with FOUR new ones (since the rack holds four). My question is: Does the charging system have any switches or adjustments that need to be made when going from two to four batteries, or does it just feed power to them until they're happy?



Eventually, I'd like to add solar and lithiums, but that's a whole other kettle of fish that I'll deal with when I can afford it. For now, I just need to know if there's anything I need to do aside from letting the system do its thing. Many thanks!! You guys rock!

[16ACE27]

Originally Posted by Choxnpinz

I apologize if this has been addressed in the past. I did a forum search and was inundated with hits, but none matched my situation. It's a rookie question, actually.


2018 Thor Chateau 31W Class-C. During the first year, it was in and out of the dealer repeatedly, and each time they left the house battery switch on, so invariably, they'd be dead as a door nail when I picked it up.



The two house batteries will only keep the residential fridge going for 10-hours before kicking the inverter offline. Other owners tell me it should be a lot more, even without solar.


I'm thinking of replacing the two 12v batteries with FOUR new ones (since the rack holds four). My question is: Does the charging system have any switches or adjustments that need to be made when going from two to four batteries, or does it just feed power to them until they're happy?



Eventually, I'd like to add solar and lithiums, but that's a whole other kettle of fish that I'll deal with when I can afford it. For now, I just need to know if there's anything I need to do aside from letting the system do its thing. Many thanks!! You guys rock!

A 14 cubic foot residential fridge draws about 30 DC amps when running through an inverter so considering a 50% duty cycle you would use 150 AHs at 12 VDC over 10 hours. Probably close to normal depending on the size of your batteries.

But, more batteries will definitely last longer and the converter doesn't care if you have one or four batteries - it will supply the current to charge them until they are fully charged - it will just take longer.

[Choxnpinz]

Originally Posted by 16ACE27

A 14 cubic foot residential fridge draws about 30 DC amps when running through an inverter so considering a 50% duty cycle you would use 150 AHs at 12 VDC over 10 hours. Probably close to normal depending on the size of your batteries.

But, more batteries will definitely last longer and the converter doesn't care if you have one or four batteries - it will supply the current to charge them until they are fully charged - it will just take longer.

Thank you, kind sir. I appreciate you taking the time to reply as well as your insight. Four new batteries, coming right up :-)

[Chateau_Nomad]

You'll soon discover with lead-acid batteries if you (or an uncaring RV dealer) abuse them they will have a VERY short life. I strongly urge you to stick a minimum of solar panels on the roof to keep your batteries topped off. Do this BEFORE you get new batteries. Once you run them below 12 volts a few times, sulfation starts killing them.

Lithium is a game changer... if you can afford it. Most of the lead-acid woes disappear when you go there.

P.S. It REALLY pi#$&@ me off when dealers TRASH RV batteries! Of all people, they SHOULD know better... but I think it's just that they really don't care... it's a low priority.

[Choxnpinz]

Originally Posted by Chateau_Nomad

You'll soon discover with lead-acid batteries if you (or an uncaring RV dealer) abuse them they will have a VERY short life. I strongly urge you to stick a minimum of solar panels on the roof to keep your batteries topped off. Do this BEFORE you get new batteries. Once you run them below 12 volts a few times, sulfation starts killing them.

Lithium is a game changer... if you can afford it. Most of the lead-acid woes disappear when you go there.

Yeah, I really can't afford the lithiums, and I was told the charging system has to be replaced with something made for lithiums, or it will only charge up to 85%. I guess I'll go to the local dealer and discuss my options for solar. I know the rig is wired for it (the connectors are on the roof) but that's where my knowledge of solar ends. Thanks a bunch!!

[Chateau_Nomad]

Originally Posted by Choxnpinz

Yeah, I really can't afford the lithiums, and I was told the charging system has to be replaced with something made for lithiums, or it will only charge up to 85%. I guess I'll go to the local dealer and discuss my options for solar. I know the rig is wired for it (the connectors are on the roof) but that's where my knowledge of solar ends. Thanks a bunch!!

My rig came pre-wired with a connection on the roof. Without doing the math, I have less than $300 in two 100 watt Rich Solar panels, and a 40 amp MPPT charge controller... I replaced the wimpy 10 amp controller that came with the rig. The bonus is you can also use that controller when you switch to lithium... just tell the controller what type batteries you have, and it knows how to cycle for them to keep them "healthy".

YouTube is your friend... many detailed install videos. I'm in Ohio, and the two panels keep my batteries constantly at 13.6 volts. The MPPT controller has a benefit over a simpler PWM controller in that it occasionally cycles to bulk charging at 14+ volts to help prevent sulfation of the battery plates.

Honestly this was one on the easiest RV projects I've ever done. And worth every penny... I NEVER have dead batteries anymore... and don't even think about it much.

[Choxnpinz]

Originally Posted by Chateau_Nomad

My rig came pre-wired with a connection on the roof. Without doing the math, I have less than $300 in two 100 watt Rich Solar panels, and a 40 amp MPPT charge controller... I replaced the wimpy 10 amp controller that came with the rig. The bonus is you can also use that controller when you switch to lithium... just tell the controller what type batteries you have, and it knows how to cycle for them to keep them "healthy".

YouTube is your friend... many detailed install videos. I'm in Ohio, and the two panels keep my batteries constantly at 13.6 volts. The MPPT controller has a benefit over a simpler PWM controller in that it occasionally cycles to bulk charging at 14+ volts to help prevent sulfation of the battery plates.

Honestly this was one on the easiest RV projects I've ever done. And worth every penny... I NEVER have dead batteries anymore... and don't even think about it much.

Since I'm completely uninformed on the subject, can you post a link to (or make/model) for the MPPT and panels you have, please? Mine has the roof wiring as well, but no idea where the wires go once they slip below the sealant.


Ironically, as much of an engineer as I was, electricity is still something I don't like to mess with, so I'm VERY reluctant to try this at home. Thanks!!

[Chateau_Nomad]

Here is an overview of my solar install:

Inside the door on our class C was a pre-installed 10 amp solar charge controller:


I replaced it with a 40 amp MPPT charge controller from Rich Solar, which is more robust and deep cycles the batteries... read up on the difference between MPPT and PWM controllers:


If you decide to swap controllers:
When you remove the mounting screws holding the old controller to the wall, pull it out slightly. You'll notice there are 4 wires attached. The connection terminal screws are labeled on the back side of the controller:

Battery "+"
battery "-"
solar panel "+"
solar panel "-"

BEFORE REMOVING WIRES!! Using a piece of masking tape (or similar) mark the wires - write on a piece of tape and attach it to each wire... then use your phone and take a CLEAR pic of the wires.

Then carefully remove each battery wire from those terminals - tape the metal ends with electrical tape as you remove them so they don't touch anything and short your battery.

The other two wires are connected to the installed solar connector on your roof. If you don't have a solar panel installed yet, just disconnect those wires - no taping needed - they won't short because no panels are supplying voltage to them yet.

Next connect the solar terminals to the appropriate terminals on the back of your new controller. Then carefully attach each battery terminal. Finally screw the new controller to the wall.

IMPORTANT!!
Depending on the type of batteries you have, you need to change your controller settings to reflect that. It shows how to do that in the instructions which come with your charge controller. Lead-acid batteries require a different type charge cycle than lithium.

This is the solar panel I purchased. I bought 2 of them. If you use 2 panels like I did, you will also have to purchase a "Y" parallel solar panel connector (search Amazon).




I also purchase mounting kits from Renogy. This has the angle plates and screws for attaching to your roof.



You will also need at least one tube of Dicor self leveling roof sealant.

After attaching the mounting bracket hardware to the panels, position them on the roof where you want. Then dab some Dicor sealant on the screws and screw them down. Finally, use a liberal amount of the sealant and COMPLETELY cover the mounting brackets where they contact the roof This is a pic taken last winter... I was checking the seal.


Then plug the panels into the connector - the plug only goes in one way. Use the Y adapter if needed. For a "tidy factor", I taped the wires down to the roof with some EternaBond RV Mobile Home Roof Seal Sealant Tape to keep them from flapping in the wind.

All items I purchased came from Amazon... so you can search there.

GOOD LUCK!

[DavidEM]

Good explanation CN. One thing I would change however. Is you wire your two panels in series rather than parallel as you did, this doubles the voltage and cuts the amps in half. Watts are the same either way.

With lower amps the voltage drop and wiring power losses are less. Only works with an MPPT controller though.

David

[Chateau_Nomad]

Originally Posted by DavidEM

Good explanation CN. One thing I would change however. Is you wire your two panels in series rather than parallel as you did, this doubles the voltage and cuts the amps in half. Watts are the same either way.

With lower amps the voltage drop and wiring power losses are less. Only works with an MPPT controller though.

David

Actually I misquoted that... Mine ARE wired in series. I just went out and checked - the controller is showing 20.9 volts (and it's overcast here in Ohio) being fed from the panels into the controller. I was going by "feeble" memory...

[dkoldman]

Is the goal here to double the battery capacity and/or to install a solar system so that when the RV is left at dealer and House Batteries are still on; the residential fridge will stay on 20 hours before batteries go dead; and/or that the solar panels will supply sufficient capacity to overcome the fridges 30 amp DC draw?

Why not simply ensure the residential fridge is OFF before dropping off at Dealer. I get even with House switch being off when you leave, dealer may have to turn it on to do something and forget to turn it off; but why leave something on with that kind of load? I don't see the Dealer needing to turn on a Residential fridge. What am I missing?

[Choxnpinz]

Originally Posted by Chateau_Nomad

Here is an overview of my solar install:

Inside the door on our class C was a pre-installed 10 amp solar charge controller:

Mine has the connections on the roof, but nothing installed inside (that I know of).

[knucklehead]

Originally Posted by Choxnpinz

I apologize if this has been addressed in the past. I did a forum search and was inundated with hits, but none matched my situation. It's a rookie question, actually.


2018 Thor Chateau 31W Class-C. During the first year, it was in and out of the dealer repeatedly, and each time they left the house battery switch on, so invariably, they'd be dead as a door nail when I picked it up.



The two house batteries will only keep the residential fridge going for 10-hours before kicking the inverter offline. Other owners tell me it should be a lot more, even without solar.


I'm thinking of replacing the two 12v batteries with FOUR new ones (since the rack holds four). My question is: Does the charging system have any switches or adjustments that need to be made when going from two to four batteries, or does it just feed power to them until they're happy?



Eventually, I'd like to add solar and lithiums, but that's a whole other kettle of fish that I'll deal with when I can afford it. For now, I just need to know if there's anything I need to do aside from letting the system do its thing. Many thanks!! You guys rock!

I replaced the 2 batteries in my 2018 Thor Windsport 29m after almost 3 years. I upgraded our Norcold fridge to a 12v system from JC Refrigeration in Indiana and love it. Problem was the batteries wouldn't stay above 12v over night when boondocking because the fridge gets power from the batteries only. I got AGM's at first and did not see ANY improvement. Napa refunded me the difference on there flooded RV/Marine batteries and they worked OK but still needed more amps. I removed the metal plate in front of the battery and the hold down and access hole piece so the tray was flat and easily installed a 3rd battery. WORKS GREAT!!!!!!!!!!!!!!!! Also I'd highly recommend the Quick-Fill system. Low water in batteries is a death sentence and it is sooooo much easier than trying to fill them with a battery fill bottle. Just attach the hose, put the end in a gallon of distilled water and pump til it's full. You can replace flooded batteries twice for the cost of AGM's and I swear I didn't see any diff!!!! Bob Trice

[blw2]

Yeah, if you don't have solar or some other way to plug in and charge while in storage
an absolute MUST is a battery post mounted disconnect switch.

After replacing far more batteries than I care to admit on boats and RV's over the years...it's now the 1st mod I'll do on anything with a lead acid battery. Disconnect even if parking only for a day.....

[dkoldman]

Originally Posted by knucklehead

I replaced the 2 batteries in my 2018 Thor Windsport 29m after almost 3 years. I upgraded our Norcold fridge to a 12v system from JC Refrigeration in Indiana and love it. Problem was the batteries wouldn't stay above 12v over night when boondocking because the fridge gets power from the batteries only. I got AGM's at first and did not see ANY improvement. Napa refunded me the difference on there flooded RV/Marine batteries and they worked OK but still needed more amps. I removed the metal plate in front of the battery and the hold down and access hole piece so the tray was flat and easily installed a 3rd battery. WORKS GREAT!!!!!!!!!!!!!!!! Also I'd highly recommend the Quick-Fill system. Low water in batteries is a death sentence and it is sooooo much easier than trying to fill them with a battery fill bottle. Just attach the hose, put the end in a gallon of distilled water and pump til it's full. You can replace flooded batteries twice for the cost of AGM's and I swear I didn't see any diff!!!! Bob Trice

You left out what type of capacity battery you had before, and what capacity battery you bought with AGM?

Doesn't matter what kind of battery you purchase; AH capacity will decide what you can and cannot do based on what you need.

I suspect you did note one difference, because a Quick fill system should not have been needed for AGM?

I got rid of my NAPA Dual FLA because I no longer wanted to do water or any maintenance after 1 year (Quick fill or not). I wanted to run a fridge overnight as well. So I dumped 2 60ah NAPA batteries and bought 125ah AGMs; so I doubled my AH capacity and got rid of all the maintenance. Yes I spent $500; but you would have to tell me how much does 2 125ah FLA cost to see ho wmuch more I paid? (if they even make them) Additionally my batteries as pure AGM has 3 to 4 times the duty cycles and can last up to 8 years. One other key point, I raised my AGS settings from starting the genset to charge batteries from 12.2vdc to 12.5vdc because I can go overnight and NOT hit 12.5 vdc with the AGMs, and be assured that I never cycle down to below 50% which is bad for both FLA and AGMs.

[knucklehead]

Originally Posted by dkoldman

You left out what type of capacity battery you had before, and what capacity battery you bought with AGM?

Doesn't matter what kind of battery you purchase; AH capacity will decide what you can and cannot do based on what you need.

I suspect you did note one difference, because a Quick fill system should not have been needed for AGM?

I got rid of my NAPA Dual FLA because I no longer wanted to do water or any maintenance after 1 year (Quick fill or not). I wanted to run a fridge overnight as well. So I dumped 2 60ah NAPA batteries and bought 125ah AGMs; so I doubled my AH capacity and got rid of all the maintenance. Yes I spent $500; but you would have to tell me how much does 2 125ah FLA cost to see ho wmuch more I paid? (if they even make them) Additionally my batteries as pure AGM has 3 to 4 times the duty cycles and can last up to 8 years. One other key point, I raised my AGS settings from starting the genset to charge batteries from 12.2vdc to 12.5vdc because I can go overnight and NOT hit 12.5 vdc with the AGMs, and be assured that I never cycle down to below 50% which is bad for both FLA and AGMs.

I'm glad your happy with the AGM's. I really was hopeful they would work for me. Based on the volt read-out on the wall of my coach, they never even fully charged. Not sure why but I was not about to pay more and get less. I'd rather pay for 3 more batteries in 3 or 4 years than spend twice as much for an AGM. Maybe if I could get them to charge and last as long as flooded, I'd go back?!?!

[dkoldman]

Originally Posted by knucklehead

I'm glad your happy with the AGM's. I really was hopeful they would work for me. Based on the volt read-out on the wall of my coach, they never even fully charged. Not sure why but I was not about to pay more and get less. I'd rather pay for 3 more batteries in 3 or 4 years than spend twice as much for an AGM. Maybe if I could get them to charge and last as long as flooded, I'd go back?!?!

If new AGM batteries would never charge, they would certainly be defective. Surely you wouldn't broad brush all AGMs batteries and all AGM Mfgs based on those 2 NAPA batteries you received defective?

Just so you know, there was nothing wrong with my 1 year old NAPA FLA 60 ah batteries. I just didn't want to do the water thing anymore, and I knew I was going to over /under with water anyway. Also I did NOT pay twice as much for my AGM batteries over FLA. I bought a different product; so to speak. My new batteries have 125ah capacity each and rated for 8 years, I more than doubled from 60ah how long I can run offline ( 20 - 24 hrs vs 6 - 8 hrs). A equivalent FLA may be $150. You purchased a 3rd battery and concede that you will buy more batteries in 3 - 4 years, an argument could be made that I actually paid a lot less, but got more.

Note: All AGMS are not made the same, so unless you specify make or model it is hard to compare. I can get very good AGMs for $180 Duracell Grp 31. I paid $250 Vmax tank Grp 31 SLR125 because I did not mind paying $60 more for Pure AGM Deep Cycle batteries with no automotive posts. My coach batteries will never be used for cranking; so a Marine dual purpose was not the best I could get for $500.

[knucklehead]

Originally Posted by dkoldman

If new AGM batteries would never charge, they would certainly be defective. Surely you wouldn't broad brush all AGMs batteries and all AGM Mfgs based on those 2 NAPA batteries you received defective?

Just so you know, there was nothing wrong with my 1 year old NAPA FLA 60 ah batteries. I just didn't want to do the water thing anymore, and I knew I was going to over /under with water anyway. Also I did NOT pay twice as much for my AGM batteries over FLA. I bought a different product; so to speak. My new batteries have 125ah capacity each and rated for 8 years, I more than doubled from 60ah how long I can run offline ( 20 - 24 hrs vs 6 - 8 hrs). A equivalent FLA may be $150. You purchased a 3rd battery and concede that you will buy more batteries in 3 - 4 years, an argument could be made that I actually paid a lot less, but got more.

Note: All AGMS are not made the same, so unless you specify make or model it is hard to compare. I can get very good AGMs for $180 Duracell Grp 31. I paid $250 Vmax tank Grp 31 SLR125 because I did not mind paying $60 more for Pure AGM Deep Cycle batteries with no automotive posts. My coach batteries will never be used for cranking; so a Marine dual purpose was not the best I could get for $500.

Were both happy so Hooray for us. I have Group 27's and each one I believe is 95ah. With three at 285ah divided by half should be 140ah's which for me is plenty. I may look into Duracell?? Do you or anyone out there know if I need to change anything on my charging system to make AGM style batts charge better AND hold a charge. The one's I had did not!!!

[dkoldman]

Originally Posted by knucklehead

Were both happy so Hooray for us. I have Group 27's and each one I believe is 95ah. With three at 285ah divided by half should be 140ah's which for me is plenty. I may look into Duracell?? Do you or anyone out there know if I need to change anything on my charging system to make AGM style batts charge better AND hold a charge. The one's I had did not!!!

You got 142ahs capacity available you should be golden, especially if adding water or maintenance is a none issue for you Lots of people like the FLA because they know them inside & out and don't mind the hassle.

In my case, before my AGMs; I only had 60ah capacity available I struggled to get through the night, throw it my disdain for adding water, the spillage the corrosion going in and out of that compartment, I just decided to solve all my problems with one swoop. I don't have the luxury as you to have 3 batteries, so I got the best AGMs with the most ah Capacity available (125ah each) which happens to be the Vmax Tanks.

With that said; the Duracells Grp 31 was my plan @ $179 each and I think 110ah. But what happened is that I started learning about the differences between Dual Purpose AGMs and Pure AGMs.

So I call Vmax tanks asking the exact same question you did about the charging. A real Technical person answered the phone, not only answering but explaining how it works. They do have special charging requirements; so it depends on your converter. I have the Progressive Dynamics with the Intelli Wizard Program. I suggest getting your converter model number and calling them. They stated that improper charging is the #1 reason the batteries fail.

In your case, it sounds like your batteries were defective because any charger should get at least 13vdc and charge up those batteries. Put a voltmeter to confirm the output of your charger on the batteries.

What they are looking for in Converters are the ones that have programs that automatically detect when and RV is being used or in storage. It adjusts the output based on the calculated stage of the batteries based on usage to avoid overcharging which can kill a AGM battery.

They offered me a discount over the Amazon pricing, and I was so pleased with the help and info; that the $60 more I paid over the AGM at Costco was a non issue. Plus I got 125ah vs the 110ah, pure deep cycle so they rated for 8 years without the automotive post. My compartment is tight; so I didn't want the extra studs if I could avoid.

[knucklehead]

Originally Posted by dkoldman

You got 142ahs capacity available you should be golden, especially if adding water or maintenance is a none issue for you Lots of people like the FLA because they know them inside & out and don't mind the hassle.

In my case, before my AGMs; I only had 60ah capacity available I struggled to get through the night, throw it my disdain for adding water, the spillage the corrosion going in and out of that compartment, I just decided to solve all my problems with one swoop. I don't have the luxury as you to have 3 batteries, so I got the best AGMs with the most ah Capacity available (125ah each) which happens to be the Vmax Tanks.

With that said; the Duracells Grp 31 was my plan @ $179 each and I think 110ah. But what happened is that I started learning about the differences between Dual Purpose AGMs and Pure AGMs.

So I call Vmax tanks asking the exact same question you did about the charging. A real Technical person answered the phone, not only answering but explaining how it works. They do have special charging requirements; so it depends on your converter. I have the Progressive Dynamics with the Intelli Wizard Program. I suggest getting your converter model number and calling them. They stated that improper charging is the #1 reason the batteries fail.

In your case, it sounds like your batteries were defective because any charger should get at least 13vdc and charge up those batteries. Put a voltmeter to confirm the output of your charger on the batteries.

What they are looking for in Converters are the ones that have programs that automatically detect when and RV is being used or in storage. It adjusts the output based on the calculated stage of the batteries based on usage to avoid overcharging which can kill a AGM battery.

They offered me a discount over the Amazon pricing, and I was so pleased with the help and info; that the $60 more I paid over the AGM at Costco was a non issue. Plus I got 125ah vs the 110ah, pure deep cycle so they rated for 8 years without the automotive post. My compartment is tight; so I didn't want the extra studs if I could avoid.

Thanks for the info and the brand. When I need to replace the FLA's I have now, I will definitely look into them and call tech support. They sound like what I wanted. I had issue's with filling them with water until I got the Quik-Fill system. Corrosion was a problem too! Maybe 3 AGM's and the proper converter for charging is the answer. Gonna do 3 days of boon-docking mid August so that will be the first real test. Thanks for the info!! Bob