Stock Coach Batteries, amp hours and the refrigerator

[Ecopco]

I goofed up. I admit it! I had my Solera parked on my driveway with the fridge on auto and no other lights etc. on.

Does anyone know about how long it will run before the batteries are drained?

Usually I keep it plugged into shore power but I forgot and went out of town. Luckily I only had some salad dressing and condiments in the fridge so it wasn't a mess. The propane was full when I left it and it burned about 1/2 tank of propane before the batteries died. I totally forgot that the fridge requires battery and propane when not hooked up to shore power or on the generator.

I drove if for a few hours and ran the generator and the batteries charged back up but I probably did some irreversible damage to the battery.

What's the next step?

If I access the coach batteries by disconnecting the battery disconnect switch do I just pop the battery cell caps and add distilled water? How much, just above the plates? What color of any should the battery water/acid be? I looked before and a few cells were clear and a few were tinted brown.

I absolutely love this forum as a first time RV owner it has been invaluable. I look forward to your reply.

Brian


2015 Solera 24R

[Sandiegodoug]

Just a question
How long did you leave it in that state, weeks or months. I just did a test on my unit for 3 weeks with my new solar system, running refer, fans, etc. no outside power but maybe I need to test longer.


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[Ecopco]

Mine was between 1-7 days. I'm not sure when the batteries gave out since I want home. I would think batteries would have lasted at least 3-4 days but they may have been weak to begin with. Solar is definitely the way to go.


2015 Solera 24R

[Sandiegodoug]

Thanks for info
After 3 weeks of off grid, 4 lights showing and voltage at 13.9
I can't believe so much propane used
Guess I'll ck that before next trip.


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[mud yapster]

435ah battery bank and 520watts solar and 3 propane tanks. LOL till my propane runs out.
If your battery was charged and you don't run out of propane it will probably go a week unless you have a lot of fans on on your fridge. like we do.

[Ecopco]

I wish I knew when the fridge stopped running. If it went almost a week then 5 gal of propane is pretty decent. If it only went a day or two then that's a lot of gas. I'm sure there's an engineer on this forum that can tell us exactly how many gallons or pounds per hour.


2015 Solera 24R

[robbdrell]

Timely post. I'm leaving town for our summer trip and intended to turn on the frig the day before we leave to cool it down. So it appears one day, actually 12, hrs will do little harm.

[clr]

Water distilled and sulfuric acid or both clear when pure, so the normal color of the battery acid is clear in a healthy battery. The brown color of the battery acid is caused by organic impurities in the liquid. That being said a slight brown color to the battery is rather normal with use and is not a sign of a defective battery. You did not state how old your batteries are. When you discharge the battery below 50% you start to degrade the life expediency of the battery the more you discharge below this point the shorter time the battery will last. If this was a one time deal you may have take a couple of months off the life of the battery but the battery will still work fine for now.

[camaraderie]

Originally Posted by Sandiegodoug

Thanks for info
After 3 weeks of off grid, 4 lights showing and voltage at 13.9
I can't believe so much propane used
Guess I'll ck that before next trip.


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At 13.9 you are reading your CHARGER in ABSORBTION!! You have NO idea what shape your battery is really in with a coach voltmeter. If you want to know you can either get a battery load tester at about $20 OR follow the following steps.
1. Charge the battery on shore power for 24 hours...it should be showing 13.2-13.4 V on your coach panel after this.
2. Disconnect the negative wires from your battery and let it SIT for 24 hours with nothing running.
3. Measure voltage at the BATTERY TERMINALS with a voltmeter. It should read 12.6-12.7 volts if in excellent condition. 12.4 V would indicate a significant loss of capacity. 12.2 would cause me to replace the batteries IF I was gonna boondock or need them to run stuff going down the road on a long trip.

You cannot measure battery condition or state of charge while charging or using it. Anyone who boondocks and NEEDS to know the condition of their battery needs a true battery monitor and shunt like the Trimetric or Victron.

[camaraderie]

Originally Posted by Ecopco

What's the next step?

If I access the coach batteries by disconnecting the battery disconnect switch do I just pop the battery cell caps and add distilled water? How much, just above the plates? What color of any should the battery water/acid be? I looked before and a few cells were clear and a few were tinted brown.

I absolutely love this forum as a first time RV owner it has been invaluable. I look forward to your reply.

Brian


2015 Solera 24R

Brian...you use DISTILLED water... not just bottled. Then pop each cap and fill to above the plated. It is good if you do this before charging the batteries but not always possible.
The color in some cells may or may not indicate a problem as the liquid should always be clear. If you want to reassure yourself about that to insure that each of the 6 cells is in good condition you'll need one of the turkey baster type hydrometers that you can get cheaply at autozone.
This measures specific gravity in each cell.
BEFORE you use it...fill the cells as above AND also give them a chance to go through a discharge/charge cycle before measuring.
Turn some stuff on in the coach 12V system for a while to partially drain the batteries for a few hours. Then plug in the coach and leave it on overnight to get a full charge on AND thoroughly MIX the distilled water and H2SO4 in each cell with a nice bulk charge. Now you can take your hydrometer readings while unplugged.
The main thing you will look for is all cells at the SAME level on the bulb.
One or two cells with different readings is a problem in the making.
If you wait 24 hours more...with the batteries unhooked at the negative wire...you can also determine the state of the entire battery even if all cells read the same.

1.265 is like new
1.225 is loss of at least 25% of capacity rating.
1.190 is less than half capacity...on its' last legs.

Good luck!

[Sandiegodoug]

So what good is the lights that come with the solera. I thought they were indicating the voltage of the system
And a digital dc voltmeter was a more accurate indicater of the charge state

[camaraderie]

Originally Posted by Sandiegodoug

So what good is the lights that come with the solera. I thought they were indicating the voltage of the system
And a digital dc voltmeter was a more accurate indicater of the charge state

First thing to understand is that coaches are set up to be plugged in at parks when they leave the factory. Most don't even come with true deep cycle batteries. The lights show you that the coach is plugged in and the converter is working. The digital readout shows the active voltage at the moment in the SYSTEM. When you unplug...it shows the ACTIVE voltage on the battery powered system at the moment...with the current loads and with any surface charge remaining on the battery plates after charging.

The lights and the meter can tell you:
Things are working.
Things are not working.
And things are dead.
Which is all you need if you plug in 99% of the time.
It cannot tell you the state of charge of the battery which requires a 24 hour wait in a static (i.e. not connected) state after charging to insure the SURFACE CHARGE is dissipated at you get a true reading.
You can eliminate the WAIT period with a load tester which can remove the surface charge. They look like this:

If you boondock you will need at LEAST a couple of hundred amp hours of true deep cycle batteries in your bank and I strongly recommend a true battery monitor that will tell you in real time the state of charge of your battery, how many amps you are pulling from them NOW, and all together so far, WHEN it is time to recharge (at 50% down ,,, not when the lights go dim) and other interesting stuff like exactly how many amps that fridge lighter uses and how much stuff still uses when you turn the battery switch to off...(parasitic loads). In addition to making your camping less worrisome... it will pay for itself by not having you replace batteries that have been murdered so often. About $150 bucks.
Disregard the above paragraph if you don't boondock.

Hope that answers your question.

Oh yeah... the maximum voltage reading for a 12V battery is 12.7 Volts if NEW and 100% charged. Anything higher and you are reading the charger/converter voltage OR the surface charge left on the battery after charging.

[Sandiegodoug]

Thanks for info
I'll buy one of those meters
My solar panels are directly connected to my battery bank via a MPPT controller, so they are kept at full charge. I boondocked on my driveway for 3 weeks, running refer, fans , other 12 volt things to test whether 200 watts of solar enough
The RV dealer tested my batteries with a fancy device that put a load on them (batteries almost 3 years old)
And each battery tested at over 1000 watts, so he claimed I didn't need to replace. I think I'll check into one of those tri star monitors. Since my panels are always charging system a meter will always indicate surface charge I guess during day.


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[Ecopco]

Originally Posted by camaraderie

First thing to understand is that coaches are set up to be plugged in at parks when they leave the factory. Most don't even come with true deep cycle batteries. The lights show you that the coach is plugged in and the converter is working. The digital readout shows the active voltage at the moment in the SYSTEM. When you unplug...it shows the ACTIVE voltage on the battery powered system at the moment...with the current loads and with any surface charge remaining on the battery plates after charging.

The lights and the meter can tell you:
Things are working.
Things are not working.
And things are dead.
Which is all you need if you plug in 99% of the time.
It cannot tell you the state of charge of the battery which requires a 24 hour wait in a static (i.e. not connected) state after charging to insure the SURFACE CHARGE is dissipated at you get a true reading.
You can eliminate the WAIT period with a load tester which can remove the surface charge. They look like this:

If you boondock you will need at LEAST a couple of hundred amp hours of true deep cycle batteries in your bank and I strongly recommend a true battery monitor that will tell you in real time the state of charge of your battery, how many amps you are pulling from them NOW, and all together so far, WHEN it is time to recharge (at 50% down ,,, not when the lights go dim) and other interesting stuff like exactly how many amps that fridge lighter uses and how much stuff still uses when you turn the battery switch to off...(parasitic loads). In addition to making your camping less worrisome... it will pay for itself by not having you replace batteries that have been murdered so often. About $150 bucks.
Disregard the above paragraph if you don't boondock.

Hope that answers your question.

Oh yeah... the maximum voltage reading for a 12V battery is 12.7 Volts if NEW and 100% charged. Anything higher and you are reading the charger/converter voltage OR the surface charge left on the battery after charging.

Thanks Camaraderie! Excellent explanation. I'll follow your instructions to see info need to replace.


2015 Solera 24R

[Ecopco]

Originally Posted by clr

Water distilled and sulfuric acid or both clear when pure, so the normal color of the battery acid is clear in a healthy battery. The brown color of the battery acid is caused by organic impurities in the liquid. That being said a slight brown color to the battery is rather normal with use and is not a sign of a defective battery. You did not state how old your batteries are. When you discharge the battery below 50% you start to degrade the life expediency of the battery the more you discharge below this point the shorter time the battery will last. If this was a one time deal you may have take a couple of months off the life of the battery but the battery will still work fine for now.

Batteries are approx one year old


2015 Solera 24R