How to Hook four Batteries in My 31W

[toolman]

I purchased a new Thor Chaeteau 31W in March 25 2015. The Two House Batteries which are Harris Part#27D170
20 Hour 160AH.
They will not run my Residential Fridge for more than 5 Hours. Can anything be suggested as to what can improve the longevity of these Batteries?

[gmc]

Originally Posted by toolman

I purchased a new Thor Chaeteau 31W in March 25 2015. The Two House Batteries which are Harris Part#27D170
20 Hour 160AH.
They will not run my Residential Fridge for more than 5 Hours. Can anything be suggested as to what can improve the longevity of these Batteries?

What is the current draw (amps or watts) of both the inverter and the fridge?
I assume EACH battery is 12v 160AH - wired in parallel gives 320AH capacity. You can't use all of that of course - don't want to run the batteries all the way down - even deep cycles...
Based on draw, can determine how long it SHOULD be able to run on good batteries...

You will find a lot of threads complaining about Harris batteries - but we can do the math to see how it is performing.

If you have the space - adding additional batteries can be done... but likely looking at a full set.

[petef]

Let me suggest your Harris batteries are garbage and likely bad. Go to Walmart and buy 2 grp 27 max marine. Or, if you got deep pockets buy a couple Trojan's. Harris won't warranty the batteries because they say it is Thor's fault for having shabby chargers on board. I think their batteries just plain suck and they are squirming out of warranty. You are not alone in this scheme, we all have been suckered.

Originally Posted by toolman

I purchased a new Thor Chaeteau 31W in March 25 2015. The Two House Batteries which are Harris Part#27D170
20 Hour 160AH.
They will not run my Residential Fridge for more than 5 Hours. Can anything be suggested as to what can improve the longevity of these Batteries?

[toolman]

Originally Posted by gmc

What is the current draw (amps or watts) of both the inverter and the fridge?
I assume EACH battery is 12v 160AH - wired in parallel gives 320AH capacity. You can't use all of that of course - don't want to run the batteries all the way down - even deep cycles...
Based on draw, can determine how long it SHOULD be able to run on good batteries...

You will find a lot of threads complaining about Harris batteries - but we can do the math to see how it is performing.

If you have the space - adding additional batteries can be done... but likely looking at a full set.

Thank you. I am going to do that. Also I will be putting in Two extra Batteries.

[petef]

Originally Posted by toolman

Thank you. I am going to do that. Also I will be putting in Two extra Batteries.

I have read those refrigerators use about 1 amp /hr when on and most people get a day or two on their batteries. You should read up on that. Your problem is when you add 2 more batteries to your bad Harris batteries the Harris will kill your 2 new ones. This is exactly what happened to me. Well, I added 1 to have 2 and the Harris killed my add on after 6 months. You plan on buying 2 batteries anyway, just buy 2 good deep cycle, replace the Harris, and see how they do. If no difference then put the Harris back in with them for 4, but I bet you won't be doing that.

[toolman]

Originally Posted by petef

I have read those refrigerators use about 1 amp /hr when on and most people get a day or two on their batteries. You should read up on that. Your problem is when you add 2 more batteries to your bad Harris batteries the Harris will kill your 2 new ones. This is exactly what happened to me. Well, I added 1 to have 2 and the Harris killed my add on after 6 months. You plan on buying 2 batteries anyway, just buy 2 good deep cycle, replace the Harris, and see how they do. If no difference then put the Harris back in with them for 4, but I bet you won't be doing that.

I am planning on buying 4 Batteries and installing them. I also want to run a 120V Plug as the only ones in my RV are in the TV Compartments.
I am not the best at this type of work but by using the Internet and You Tube I should be able to do all the work myself.
Thank you,
Butch

[toolman]

Originally Posted by toolman

Thank you. I am going to do that. Also I will be putting in Two extra Batteries.

I am planning on buying 4 Batteries and installing them. I also want to run a 120V Plug as the only ones in my RV are in the TV Compartments.
I am not the best at this type of work but by using the Internet and You Tube I should be able to do all the work myself.
Thank you,
Butch

[toolman]

Originally Posted by gmc

What is the current draw (amps or watts) of both the inverter and the fridge?
I assume EACH battery is 12v 160AH - wired in parallel gives 320AH capacity. You can't use all of that of course - don't want to run the batteries all the way down - even deep cycles...
Based on draw, can determine how long it SHOULD be able to run on good batteries...

You will find a lot of threads complaining about Harris batteries - but we can do the math to see how it is performing.

If you have the space - adding additional batteries can be done... but likely looking at a full set.

I am planning on buying 4 Batteries and installing them. I also want to run a 120V Plug as the only ones in my RV are in the TV Compartments.
I am not the best at this type of work but by using the Internet and You Tube I should be able to do all the work myself.
Thank you,
Butch

[Chance]

The battery 27 group size is likely 80 Amp-hours per battery at 12 Volts and not 160 Amp-hours each (as assumed by GMC). If it were a 6-Volt battery it could easily be rated at 160 Amp-hours each, but since the two would end up in series instead of parallel (as done with 12-Volt batteries) then we'd still be at 160 Amp-hours total at 12 Volts.

Assuming batteries are in great shape, and state of discharge is limited to 50% for design purposes, then we'd expect 80 Amp-hours of usable capacity.

If a fridge draws 1 Amp on average (and that's at 120 Volts AC), then the inverter will need a little over 10 Amps of 12-Volt DC juice from batteries. And if battery energy is limited to 80 Amp-hours, then fridge may run up to 8 hours provided nothing else is operating (and also that batteries start at 100% of rated capacity).

One can quickly see why residential refrigerators often come with 4 fairly large quality batteries. Combined with the fact that the refrigerator normally doesn't operate 100% of time, and that batteries can go below 50% state-of-charge, it's easy to predict up to 1 to 2 days of operation.

Obviously a more efficient refrigerator will run longer on same batteries. A more efficient inverter helps a little too, as well as when refrigerator is in cool camper versus one in hot camper. There's a lot to consider when estimating run time.

[Yosemitebob]

I use two 6v batteries wired parallel, Each battery is rated at 232AH in parallel it stays the same only voltage adds up, hence I have 12v at 232AH. Plenty as long as i start out full. We run the refer, and two TV's during the night, handles it right nicely. But then I have 400w of solar power on the roof too, to bring them up to charge again during the day. The more batteries you have, means longer charge times as well. Figure out your needs, you may not need four batteries.

[BCRacing24]

Originally Posted by petef

Harris won't warranty the batteries because they say it is Thor's fault for having shabby chargers on board.

Actually Thor does use shabby chargers, WFCO chargers are sub-par when new and plain junk after only a few years of use....... Replace ASAP !!

[Chance]

Originally Posted by Yosemitebob

I use two 6v batteries wired parallel, Each battery is rated at 232AH in parallel it stays the same only voltage adds up, hence I have 12v at 232AH. Plenty as long as i start out full. We run the refer, and two TV's during the night, handles it right nicely. But then I have 400w of solar power on the roof too, to bring them up to charge again during the day. The more batteries you have, means longer charge times as well. Figure out your needs, you may not need four batteries.

That's a nice system you have there, particularly if you camp off grid during the day. I was intrigued to figure out how the solar "may" affect relative capacity (very rough estimate without much details).

Like you say, it's not about the number of batteries, but their size/capacity and how much energy and/or power the user needs. In your case it appears that your two batteries are considerably larger or of greater capacity than those of the OP. By the way, I think you probably meant to say your two 6-Volt batteries are wired in series, not parallel.

Most entry-level motorhomes I've looked at have house batteries rated around 80 Amp-hours each (must be common size), which gives the equivalent of 160 A-hour if it were 6-Volt. Since your two batteries are rated 232 Amp-hours, it makes them close to 3 of the ones often installed by manufacturers (obviously they can vary based on MH cost or other factors).

In your case solar could make all the difference. In rough numbers, a typical house battery like installed in many Class Cs can supply 1 kW-hr of energy. But since batteries should be limited to around 50% discharge, that means most owners will get about 0.5 kW-hr (500 watt-hours). So the common two-battery system can only supply 1 kW-hr of energy before it needs recharging.

By comparison, your 400-watt solar system may produce 2 kW-hrs or more on a sunny day. That's the equivalent of 4 Harris 80 Amp-hour X 12-Volts batteries if discharged to 50%. And if you add that your batteries are also larger (close to 3 Harris 80 Amp-hour X12-Volts), then your system can supply far more energy on a 24-hour daily cycle. I'd guess at least 3 times more.

I'm not defending Harris batteries in any way, but it's easy to see that if an owner only has two 80 Amp-hour X12-Volt batteries (total of 1 kW-hour of useable energy), then they have to limit power consumption to less than 50 Watts average in order for it to last a full 24-hour day. And that's not likely to work if owner runs a large residential refrigerator on a warm day.


I'm curious if your solar controller tracks how much energy the system provides daily. Do you ever get around 2,000 watt-hours in a 24-hour period? Whatever it is I'm sure it's extending your capacity significantly.

P.S. -- Sorry for length of reply, but how battery capacity will affect the future of RVing is an exciting subject to me.

[Yosemitebob]

thanks Chance, I spend some time on past systems and I think I got it "mostly" right on this coach. Yes, we spend a lot of time boon docking and other times off the grid just because we like it, noise free, anyway, yes I keep a close eye on the functioning of the system. A month ago, I replaced my stock converter to a Truecharge2 - 60a with remote which is a full function remote that allows "me" to set the maximum charger output current, temperature, faults and warnings and what I like it displays the current status of each battery or each battery bank and many other functions, including equalization and at what current it should work at. A good equalization should be done as per battery spec but no stock controller can do that even when it gives you a 2 hour equalization at 14.2 ha, I can get the full 14.8 with mine. Did you know, that most batteries with the current controller/chargers do not charge your battery to full, they are made that way purposely. If you want or need to use your upper 10% of your battery, you have to start out with a full battery which means you have to have a controller you can "control". My remote is new, so I will not have numbers until this summer when we give it the true test . My controller for the solar is also an MPPT40a, as it also needs to have the same function as the shore driven controller. Batteries, people put to little thought into these. They are important that is why I mentioned one needs to know what they want out of it, and then don't overdo it. My system now has just two batteries as I mentioned, I may add two more but they will be on a separate system if I do that, with switching. If I had four batteries, I would not be able to charge from 95 - 99 percent full unless I added solar panels, two more for 600, I really didn't need more. It's all about monitoring and I'm setting myself up to do just that. So, I guess what I'm saying is better batteries, better controllers. I also might add, flooded batteries are still the best, not that you can't use AGM and others. I think I've said enough, I get carried away sometimes, besides my wife is calling me for breakfast

OH, yes, I did mean to say in series not parallel

[Chance]

I agree it's very important to first figure out how RV will be used. And what makes the best solution for each owner so complicated are all the different sources of energy that can be used. There is shore power, propane, solar, engine alternator, etc... And to smooth out peaks the use of batteries is critical, especially now that the RV trend is shifting towards more electric. In any case it seems you can't go too wrong with more battery capacity (except cost and weight).

I was recently reading about a new EarthRoamer built on F-750 4X4 chassis which incorporates 25.3 Kilowatt-hours of battery capacity, 2.4 Kilowatts of solar, and 2 X 3,000 watt inverters. For now the cost of this much technology can only be absorbed by mega-expensive motorhomes, but the cost seems to be declining fairly fast so it may filter down over the next decade or so.

I'm personally looking forward to the day that battery capacity is inexpensive enough to make an all-electric motorhome without a generator practical for us to own. We are almost there now, but lithium batteries need to drop in cost a bit more. And it would also help if more OEMs offered engine choices with second alternators. They are already options on M-B Sprinters, RAM trucks, and Ford diesels, but no mention yet on Ford RV chassis like F-53 or E-Series.

[Yosemitebob]

Very true, I forgot to mention I also have the "Link-10" specific battery monitor, I know, a bit overkill, maybe, but being how we will stay in the middle of a desert to the middle of a mountain medow (if I can get to it) for sometimes two or more weeks, I figured it won't hurt. I only had to use the generator when in the mountains, as I don't aways get the amount of sun needed, yep there are limitations to solar as well. That EarthRoamer is some animal, but for as big and awesome as they are, they don't have a lot of living space, but I wouldn't mind cramping my style When I picked up this motorhome ( F550 diesel) I had them add the second alternator, I knew I would need it along the way.

I'm a retired cartographer, and that would be right up my ally for sure

[toolman]

Originally Posted by BCRacing24

Actually Thor does use shabby chargers, WFCO chargers are sub-par when new and plain junk after only a few years of use....... Replace ASAP !!

I Purchased Trojans 30XHS T2 12V 130AH @ 20Hours. I am going to put in Four New Batteries. These cost me $208.00Ea.
I also bought Solar Panels. Renogy 200 Amp Solar Panels, 2000 Watt Inverter, Controller. I hope to figure out how to install these items without screwing up my Coach.
Any help out here?

Toolman

[toolman]

Can we talk via email? I think maybe you could help me with my system.
I Purchased Trojans 30XHS T2 12V 130AH @ 20Hours. I am going to put in Four New Batteries. These cost me $208.00Ea.
I also bought Solar Panels. 2 Renogy 100 Amp Solar Panels, 2000 Watt Inverter, Controller. I hope to figure out how to install these items without screwing up my Coach.
My email is lockwood539@yahoo.com.
Thank you,
Butch

[toolman]

Ok lets say I have hooked up a solar system and it's now charging my Battery Bank and the Batteries are sending 12Volts to my Newly installed Inverter.
What do I do now? I have to send that current into my existing system. My existing system seems to be controlled by a WFCO Power Converter with distribution panel Model #WF-8955PEC. I have no clue how to tie into my old system. Any help out here.

[toolman]

Ok lets say I have hooked up a solar system and it's now charging my Battery Bank and the Batteries are sending 12Volts to my Newly installed Inverter.
What do I do now? I have to send that current into my existing system. My existing system seems to be controlled by a WFCO Power Converter with distribution panel Model #WF-8955PEC. I have no clue how to tie into my old system. Any help out here?

[Yosemitebob]

You can do that a couple of different ways. you can use the output on the inverter and install some recepticals in the places of your choice, run wire to those, or disconnect that TV circuit from the braker panel, run that to your output. And sense you need a breaker for the inverter anyway, run another wire from the braker you disconnected and run that to your input. I don't have a inverter/charger combo, I only have a inverter and seperate converter charger. So, I would have to see what you have on the inverter if it's the same electrical hookups as just the inverter. Can you put the diagram on here?


Sorry, I wrote this really fast as I'm still at work