Battery question using Alde and Fridge

Barteur

Hello everyone,
Glad to be here, just purchase A Tabitha nucamp model a month ago and trying to figure out a few things. 
I would like to know if its normal that after 15 hours of usage of the Alde and Fridge on propane mode and asking the Alde to raise interior temperature only 5 to 8 degC ( was 9 degC outside and i ask for 15 deg C) my Battery goes down 10.3 volt.
Heres the test I did:

Started at 10am turned on fridge and Alde on propane battery reading 14.3v

@ 11am 12.7v until 15h

@ 15h 12.5v until 20h, since it has no moved for a while I let it run for the night @ 5:45 next morning 10.3v and the system was in automatic shut down. I have attached a spec of the battery I have for reference. Thanks in advance.

RollingBnB

First question, which model Tab, what year and which frig. If it’s a 3 way fridge I’m surprised you went that long. Was the fridge on propane or battery?

Barteur

RollingBnB said:

First question, which model Tab, what year and which frig. If it’s a 3 way fridge I’m surprised you went that long. Was the fridge on propane or battery?

Hi, it’s the Tabitha 2016, the fridge was on propane as well with the internal fan off

BrianZ

I would not have expected that to happen if both were on propane.  Our recent boondocking experience showed we used about 18AH per day total for the trailer, including frig & Alde on propane, water pump, lights, TV, phone charging, cell signal booster, very little fan usage (lower than lowest speed & only while cooking) & background electronics. 

You should have had at least 35 AH available on a fully charged group 24 battery.  Is it possible you had one appliance set to the wrong power source?  Or maybe try a different meter for the voltage measurement - at that low voltage, battery should be dead.  How old is it?  By the way, I wonder about your battery's AH rating spec.  Seems too high for a gp24 battery & maybe not using the standard 20-hr rating?

If voltage was accurate, I suggest using a refractometer or hydrometer to check specific gravity of each cell, if possible) to make sure you don't have a bad cell (no more than 0.030 difference in any cells).  If so, run a charger equalization mode if available & appropriate, then check again.  If persists, the battery may be bad.  Or have it tested.

pthomas745

And, how and when was the battery tested?  If there was still a load on the battery, and not "rested" it will show much lower than you might expect.  Turn off the battery switch, wait a couple of hours, and test it again.

On the table below, you have to be careful that you are not just measuring the surface charge. To properly check the voltages, the battery should sit at rest for a few hours, or you should put a small load on it, such as a small automotive bulb, for a few minutes. The voltages below apply to ALL Lead-Acid batteries, except gelled. For gel cells, subtract .2 volts. Note that the voltages when actually charging will be quite different, so do not use these numbers for a battery that is under charge.

Barteur

Thanks for the comments. If I want a 12 v battery that would give me 2 to 3 days autonomy for the fridge on propane, Alde on propane et I would say a few hit at the pump for the sink. What size should I be looking? Reading Brian i could potentially think I need about (18-20ah X 3) and I think I need to double that as a minimum so anything above 140 should be fine? I think my battery is toast, I don’t know what the previous owner did or maintain proper charge level so I might just go for a new one or maybe 2 6v.

Barteur

BrianZ said:

I would not have expected that to happen if both were on propane.  Our recent boondocking experience showed we used about 18AH per day total for the trailer, including frig & Alde on propane, water pump, lights, TV, phone charging, cell signal booster, very little fan usage (lower than lowest speed & only while cooking) & background electronics. 

You should have had at least 35 AH available on a fully charged group 24 battery.  Is it possible you had one appliance set to the wrong power source?  Or maybe try a different meter for the voltage measurement - at that low voltage, battery should be dead.  How old is it?  By the way, I wonder about your battery's AH rating spec.  Seems too high for a gp24 battery & maybe not using the standard 20-hr rating?

If voltage was accurate, I suggest using a refractometer or hydrometer to check specific gravity of each cell, if possible) to make sure you don't have a bad cell (no more than 0.030 difference in any cells).  If so, run a charger equalization mode if available & appropriate, then check again.  If persists, the battery may be bad.  Or have it tested.

About the wrong power source question I’m pretty sure I did it right will check again. And I will do only heat et then only fridge to see...

BrianZ

Sounds like you may not know the age or true condition of the battery.  I suspect it may be bad. 
We recently replaced our standard group 24 battery with a single 12V golf cart battery (which fit in a larger group 27 battery box) to get 150 AH (75 available for discharge at the recommended 50% limit), so we could last 3-4 days if needed.  Then we added a solar panel to recharge & last even longer.

Barteur

BrianZ said:

Sounds like you may not know the age or true condition of the battery.  I suspect it may be bad. 
We recently replaced our standard group 24 battery with a single 12V golf cart battery (which fit in a larger group 27 battery box) to get 150 AH (75 available for discharge at the recommended 50% limit), so we could last 3-4 days if needed.  Then we added a solar panel to recharge & last even longer.

Thank Brian👍🏻

Barteur

I ended up installing a group 31, need to test if it will last but looks promising. Thanks all for the feedback it helped making a good choice. 

Dcarlton

I just got back from the beach here in California over the Thanksgiving holiday.  I was dry camped for four days at Morro Bay.  I was out surfing during most of the days.  The fridge was on propane the whole time. I used the Alde at night and in the chilly early morning hours before paddling out. In the evenings, I listened to the Jensen and used some lights. On the 4th day I was at 12.1.  I took a shower on day 4, running the water pump a bit, and it magically went up to 12.2. So, four days and I’m at 12.1 to 12.2.  It’s a 2018 320 with the battery that came with it.  I think I could probably go another day or two. I think that’s pretty good! I’ve done a bunch of one and two night trips.  This was the longest.  I’m pretty happy with the battery performance.

I was also really comfortable and loved being in the Tab, especially after years of sleeping in my car on surf trips! 

dsfdogs

@BrianZ did your new group 27 battery box fit ok in the tub without modification? Thanks

mreric

Dcarlton said:

I just got back from the beach here in California over the Thanksgiving holiday.  I was dry camped for four days at Morro Bay.  I was out surfing during most of the days.  The fridge was on propane the whole time. I used the Alde at night and in the chilly early morning hours before paddling out. In the evenings, I listened to the Jensen and used some lights. On the 4th day I was at 12.1.  I took a shower on day 4, running the water pump a bit, and it magically went up to 12.2. So, four days and I’m at 12.1 to 12.2.  It’s a 2018 320 with the battery that came with it.  I think I could probably go another day or two. I think that’s pretty good! I’ve done a bunch of one and two night trips.  This was the longest.  I’m pretty happy with the battery performance.

I was also really comfortable and loved being in the Tab, especially after years of sleeping in my car on surf trips! 

wow,  that pretty good usage,  looks like all you need is small solar panel.   12.1-12-2 would be suggested limit before causing decreased life on the battery -

BrianZ

Congrats on your new battery, @Barteur - that sounds like a nice upgrade.

@dsfdogs, if you scroll down to the 5th message on this page, I showed what I did..
http://tabforum.nucamprv.com/#/discussion/3847/what-battery-should-i-upgrade-to/p3 
My group 27 box fit in the tub, but not without modification of the tray underneath to secure it.  I had to build a new & longer metal tray to bolt on top of the old group 24 sized tray that is welded to the tub frame, as others like ScottG had done before me.
My new 12V GC2  battery fits inside the group 27 box, but it's a half inch too tall so the lid does not snap shut on both sides - it snaps closed on one side & the tab on the other side fits inside the slot but does not snap shut, though it is held snug by the strap that clamps shut over the top.

Barteur

Fyi the group 31 fit similar as yours Brian just more angled... ended up a pretty easy upgrade. Thanks for the idea gave me a place to start 👍🏻

Barteur

Dcarlton said:

I just got back from the beach here in California over the Thanksgiving holiday.  I was dry camped for four days at Morro Bay.  I was out surfing during most of the days.  The fridge was on propane the whole time. I used the Alde at night and in the chilly early morning hours before paddling out. In the evenings, I listened to the Jensen and used some lights. On the 4th day I was at 12.1.  I took a shower on day 4, running the water pump a bit, and it magically went up to 12.2. So, four days and I’m at 12.1 to 12.2.  It’s a 2018 320 with the battery that came with it.  I think I could probably go another day or two. I think that’s pretty good! I’ve done a bunch of one and two night trips.  This was the longest.  I’m pretty happy with the battery performance.

I was also really comfortable and loved being in the Tab, especially after years of sleeping in my car on surf trips! 

This is exactlt what triggered my original question since the seller told me i sho7ld have that type of longevity... but now i know my battery was a bad one.