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Adding one more house battery but where?

Yahoo Message Number: 65253
I'm sure there are many of us with the older intrigues that wish we could add a third house battery.
With all the talk about Norcold refrigerators and I want this coach to be next to the convenience of home when I am in it, I am going to replace my norcold with a residential Samsung Refrigerator. I have room for only two 8D House Batteries in the battery compartment of the 2004 intrigue ovation (moneypit). My travels will always take me off grid.
There is room back there if I redo part of the inverter shelf/box and make it smaller. I can add an upper battery shelf to hold one more battery. I do welding so this seems like a DIY project.
Question? Has any one done this to one of these coaches that just has three batteries in it, (starter and two house batteries). I just put two new 8D AGM batteries in it and will add another since they do not need to have water added and space will be a premium.

Any ideas or pictures?

Dallas 2004 intrigue ovation 42' tag C12

Re: Adding one more house battery but where?

Reply #1 –
Yahoo Message Number: 65255
Dallas,

I accomplished just what you are trying to do, on a temporary basis. I have 540 watts of solar, and have three 8D lead acid batteries house batteries in addition to the starter battery. I devised a hoist to get the third 8D in and out of the space. I rested the third battery on a 2x4 frame work that distributed the weight of the third battery over the other three already installed. A true PIA, as I have to remove the extra battery to check acid levels in all of them.
So......I designed a pivoting tray that will accomplish moving the third battery out of the way - the frame work of the bay is handy to tie to. I decided to not build it, because I do not have welding skills, and did not want to be prototyping what could be an expensive gadget. Now, if someone made one up, I would sure look at it. My batteries should last another five years the way I baby them. Not sure I would recommend welding to existing bay framework, but punching holes and bolting it will work well. In the mean time (while I am on full hookup) I moved the third battery to storage and charge it with a stand alone charger.
All that said, when I replace the batteries the next time, it will be with L-16 (?) AGM batteries to maximize battery capacity for the space available. Or, I will be open to suggestions if I am still full timing. By then hydrogen fuel cells will probably be available. ;*) Jack Nichols, 2003 Intrigue, 11527

Re: Adding one more house battery but where?

Reply #2 –
Yahoo Message Number: 65272
Dallas: If you intend to spend a lot of time off the grid, I suggest that you do some serious math before changing to a residential fridge. If it draws 12 amps at 120 V, that's 120 at 12V. We have 6- 6V AGM batteries which give us 900 amp hours of storage (450 useable). We also have 4- 130w solar panels. If the fridge runs 20% of the time (probably more in hot climates) I think our system might just keep up to a residential fridge (if the sun shines and if the panels get to see it all day). We wouldn't be able to use anything else. We spend about 1/2 of our days off grid (unless parked for an extended period) and I would not want to run a domestic fridge with our system. The fridge runs on propane when we are not connected and that makes everything else good to go on the coach without having to run the generator for extended periods twice a day. Normally, we don't run the generator at all.
Just the way I have experienced it. Maybe someone else has off-grid experience with residential fridges.

Richard Owen '05 Inspire 51442

Adding one more house battery but where?

Reply #3 –
Yahoo Message Number: 65275
Another alternative is to replace the two 8D batteries with Trojan T-105 batteries. There is a photo of my installation somewhere in the CC photo section of how I managed to put 8 of these 6-volt batteries in the space where the two 8Ds house batteries were.
photos/album/2058978311/pic/list This gives me 900 amp-hours based on the Trojan specs of 225 amp-hours per 12 volt pair. I did a similar installation on a previous coach and when I sold it after 8 years those Trojans were still good as new. This 8-battery set in my 2002 Intrigue is now 6 years old and they still seem as good as new. I also have 500 amps of solar and the batteries are all accessible for checking and filling but twice a year is about all they seem to need attention and I'm a pretty big energy hog and do a lot of boondocking.

Steve

2002 Intrigue #11382

Re: Adding one more house battery but where?

Reply #4 –
Yahoo Message Number: 65282
Hi Richard,

I came across this article that convinced me of what I want to do and how much energy will be consumed by the refrigerator. The person who worte the article had pretty much the same refrigerator and was using 15AH at 12 volts for 20 minutes every hour or 5AH per hour avg. Total AH with all the paracite draws on the inverter was about 140AH over an 8 hour period (overnight without using a generator). He also had some solar panels that would keep up with day use. Very interesting article.
http://www.happy-wanderers.com/technical-articles/159-residential-refrigerator-power-requirements
Dallas 2004 intrigue ovation c12 11688

Re: Adding one more house battery but where?

Reply #5 –
Yahoo Message Number: 65283
Our last coach was a custom bus conversion. We had 1700+ amp hours of batteries and ran a residential fridge.
The key was replacing the fridge compressor with a 12 Danforth. Fridge ran for 6 years with out a problem.

Bruce 2001 Intrigue #11278

Adding one more house battery but where?

Reply #6 –
Yahoo Message Number: 65284
If you are an occasional short time boondocker, then maybe this might work for you. You can bet when our Norcold gives up, I will be headed in this direction. We have a houseboat that had a Norcold with the same issues as many of us have experienced. I replaced the unit with standard home refrig, top freezer, ice maker, 2 door 18 cubic foot unit. The frig was rated for 700 watts. I powered the frig with a 1000 watt inverter and 2 8Ds. The frig will run about 1/3 the time, drawing well over 50 DC amps when running. After 8 to 10 hours the batteries are at 12.4 volts. Not bad. A short gen run tops the batts. When I do this to our Inspire, 6 golf carts will be the power source being more than the 2 8Ds for the other power usage. Probably will use a separate smaller inverter (than the 2000 on the coach ) for refrig power only.
Ned Herrmann
06 Inspire 51677

Re: Adding one more house battery but where?

Reply #7 –
Yahoo Message Number: 65337
Dallas: I did read the article and it's a pretty good accounting.
Solar is a great source of power but it is highly dependent on the ambient conditions. Trees, clouds, etc. get in the way.
I have watched our system and I think it will average about 100 AH per day in normal conditions. Max is about 170 on long summer days.
We have had some weeks off grid where we run completely without generator if we avoid long oven usage (lots of BBQ).
I think the decision comes down to how much you want to run the genset.
I will admit that if we had any serious problems with our fridge, I am now more likely to consider it than I was before.

Richard Owen '05 Inspire 51442

Re: Adding one more house battery but where?

Reply #8 –
Yahoo Message Number: 65338
Richard,

Do you the need for more battery power? I was not sure from the email.

Inspire 2005 51406
Stan

Re: Adding one more house battery but where?

Reply #9 –
Yahoo Message Number: 65339
Stan: No, I can't afford any more weight. From here on, it's power management. Did you buy that new coach?

Richard Owen '05 Inspire 51442

Re: Adding one more house battery but where?

Reply #10 –
Yahoo Message Number: 65341
Richard,

I bought the coach new, and found that having air asst. all night drained the battery more than I would have liked. Therefore I had installed two additional batteries in the current battery compartment. This solved all the problems.

Stan 51406 Inspire 2005

Adding one more house battery but where?

Reply #11 –
Yahoo Message Number: 65343
Thanks for the feedback Steve,

I just bought 2 8d AGM batteries a few weeks ago. Your set up look very straight forward. Wish I had figured on putting in a residential Regriferator before replacing the batteries.
I have a new 4d Flooded battery laying around and if that will crank my C12 engine, I will take out my Flooded 8D battery and put another 8D AGM battery with the other two and then I will have 765AH. I can stack the 4D in front and on top of the AGMs on the lower shelf by building a shelf in front of the enclosed Inverter box.
The big question is weather the 4D will crank a C12 with only 26,000 miles on it.

Dallas

Re: Adding one more house battery but where?

Reply #12 –
Yahoo Message Number: 65368
I read that article as well. I don't see how it does it. seems impossible. there is a major inaccuracy in the article: that fridge draws 15 ac amps not dc amps. So multiply his numbers by roughly 10.

Rich 2002 magna.

Re: Adding one more house battery but where?

Reply #13 –
Yahoo Message Number: 65371
Dallas, Lots of possibilities with cranking your C-12. The key word is crank. The main reason for 2 8D's is getting the diesel to fire up quick. Cranking over and over is not a good thing with high compression. The hardest wear occurs when you start or stop your engine I'am told. Lots of truckers prefer to leave the engine run. When we stop at a rest area I rarely shut down.
Leonard, can probably comment on this subject, much better then me.
AL

00 affinity

Re: Adding one more house battery but where?

Reply #14 –
Yahoo Message Number: 65376
Rich,

I know the fridge draws less than 15amps/14 gauge wire. That is the required breaker and wire size mentioned in the data sheet. The refrigerator uses 445 kWH per year (according to the energy rating guide). So if I do the math, I get 445 x 1000 watts = 445000 watts per year. Then devide this by 365 days and 24 hours in a day (8760 hours in a year) and I get 51 watts per hour on average. (Same as a 50 watt lightbulb) Question is, how long does a 50 watt lightbulb take to reduce a battery by 50% of charge?
We know that a frige runs only about 2o minutes and hour but that is not important for the total number. By my caculations 51 watts at 120 volts is something in the neighbor hood (taking into account intervert iniefficiency) about 510 watts at 12 volts or (510/12)= 42 amps in battery draw per hour.
That would means that it would take Two (2) 8D batteries to supply 5 hours of reserve, or five(5) 8D's = 12 hour. I am thinking of installing a total of Three (3) 8D's house batteries so by interpolation I get about 7-8 hours.
This does not include other paristical draws, just the refrigerator. Uhm....maybe I need 4 batteries...... :(
Here is an interesting web site to do these calculations. Pick your amp draw and battery size to figure out the results.
http://www.lifelinebatteries.com/marinesizing.php
Dallas

Re: Adding one more house battery but where?

Reply #15 –
Yahoo Message Number: 65384
Dallas,

I belive you have a flaw in your calculations. 445kwh x 1000 is 445000wh not 445000w. One measures the amount of power while the other measures the rate of power flow.

Don Seager

2004 Allure 31046

Re: Adding one more house battery but where?

Reply #16 –
Yahoo Message Number: 65385
Dale,

There should be a nameplate on or around the compressor area or on the back of the fridge stating RLA (Run Load Amps) and LRA (Locked Rotor Amps) and the rated voltage and frequency of the unit.

Example:
Volts = 120
Hz = 60
RLA = 1.2
LRA = 14

There may be other numbers as well, for icemaker, defrost heaters, power factor, etc.

The RLA number is the amp draw while the unit is running normally. The LRA is the maximum current required when the compressor starts, and is important when sizing an inverter and supply wiring.

The nameplate is the best place to start to determine the required power. If you can't find it, or don't have access to it, a "Kill-a-Watt" meter, which can be had for around $20, will tell you everything except LRA.
Dave

2000 Allure
#30444

Re: Adding one more house battery but where?

Reply #17 –
Yahoo Message Number: 65415
This residential fridge/battery thread has probably outlived it's usefulness but to simplify, I think the 4A draw when running is probably as good as it gets so if that happens for 33% of the time it works out to (4X.33X10X24) 316 AH DC per day.
I had calculated in the past that with a propane fridge running I would expect to use a total of 150-200 AH per day. That was what determined our solar and battery storage capacity to provide power indefinitely if the ambient conditions supported it.
So it looks like the load with a res. fridge would be about 450 AH DC per day - total. That's a lot of generator time each day - certainly more than a few hrs. if you want to get into the float charge area.

Richard Owen '05 Inspire 51442
 

Re: Adding one more house battery but where?

Reply #18 –
Yahoo Message Number: 65417
Dale, I think you are about right, 40-50 dc amps per hour just for fridge, but that is a lot when boondocking! 320 overnight. All I am saying is can do, but his numbers are way optimistic. yes I think you would definitely need 4 8d batteries.

Rich 2002 magna