Ran out of 12 DC @ 3 AM 1st night.

[Gundog]

Our first boon dock night in our new to us MH and the 12V DC went dead. When I bought the coach they told me the batteries were fairly new I need to see if they have dates on them. Now for the use maybe I am expecting too much.

The coach was plugged in for several weeks before we left on the trip so the batteries should have been fully charged. We drove around 2 hours to our destination. While driving we had the inverter on to play the stereo system. When we arrived we left the inverter on plus a few lights all LED. We watched a couple movies and it was fairly cold with the heater coming on and off very frequently. I also sleep with a CPAP machine so I need the inverter on for that machine.

At 3 AM I woke up to an alarm beeping. I checked the battery voltage and it was down to around 9 volts. I had to start the coach and let it run for a couple minutes to start the generator. I let the generator run until about 6 AM.

I can run my CPAP machine off 12 volts but I would need to wire a 12 volt receptacle next to my bed. Do the inverters draw a lot of power if they don't have a large load on them?

Had I run the generator before going to bed we would have probably been OK but it seems it should have lasted longer than it did.

I have a large solar panel on top and I know that does nothing at night but I am just giving all the particulars of my system. My battery bank for the house is 4 - 6 volt golf cart type batteries.

This is our first RV with an inverter so I don't know what to expect.

[MRUSA]

Even a new battery that is run dry and drops to 9 volts may be irreversibly damaged. For long battery life a bettery should not be discharged more than 50%, which is at approximately 12.0 volts.

[Gundog]

down home wrote:

Gundog wrote:
After the batteries went to 9 volts and I ran the generator for 3 hours they read 12.6 volts. I don't think they are gone but they are definitely not great. I have been charging them for 2 days now after adding the water so I will just have to see. I haven't had time to mess with it again. If the batteries are junk come spring I will replace them.

Should have read 13.5 or so.
Batteries are going down.
Carbon leak down test for reg auto batteries should work for house batteries.What that does is place a load on the batteries to see if it will carry them or go down quickly.
Did thee Salesman say replaced recently, like since he was born?

I did not buy it from a dealer I bought it private party. I believe they are fairly new but they were not maintained. These batteries have no date codes that I can find so who knows.

[down_home]

Gundog wrote:
After the batteries went to 9 volts and I ran the generator for 3 hours they read 12.6 volts. I don't think they are gone but they are definitely not great. I have been charging them for 2 days now after adding the water so I will just have to see. I haven't had time to mess with it again. If the batteries are junk come spring I will replace them.

Should have read 13.5 or so.
Batteries are going down.
Carbon leak down test for reg auto batteries should work for house batteries.What that does is place a load on the batteries to see if it will carry them or go down quickly.
Did thee Salesman say replaced recently, like since he was born?

[2manytoyz]

It's often difficult to find the actual current inverters draw with no load. I have a number of them, so I did my own testing.

Inverter Idle Current

As it turns out, the RV we recently purchased, has the same model PROwatt SW2000 inverter I've been using 24/7/365 since 2012 with my solar setup on my home.

From what I've read online, a furnace typically draws 8-11 Amps when running. That's a lot, but a healthy battery bank shouldn't have had a problem overnight.

Might be time to have each of your batteries load tested. Here's what I've used: https://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

Good luck!

[time2roll]

Gundog wrote:
After the batteries went to 9 volts and I ran the generator for 3 hours they read 12.6 volts. I don't think they are gone but they are definitely not great. I have been charging them for 2 days now after adding the water so I will just have to see. I haven't had time to mess with it again. If the batteries are junk come spring I will replace them.

You should see charging at 14+ volts. As a test let them charge 48 hours and then fully disconnect and separate the batteries. Let them rest 48+ hours and recheck the voltage. Should hold 6.35 volts.

Even if they hold voltage and are serviceable they may have significant capacity loss due to low electrolyte.

[oldave]

After charging ,the batteries need to rest for awhile before a volt reading
will tell much .
Actually volt reading will not tell much unless it is under load .
Any old battery can be made to read volts right after charging but it may
fade quickly when even a small load is applied .
A hydrometer along with a load test is probably in order .
You can buy a hydrometer at Walmart or auto parts and do that test yourself,
you'll probably need to visit somewhere for a load test .
I have been very happy with the service received at Interstate battery stores.

[Desert_Captain]

The solution here is to test them with a simple hydrometer. All of the cells should test nearly the same {doesn't matter if they are all high, medium or even low} if just one cell is way low relative to the others that is a bad cell and no amount of charging will ever bring it back. As soon as you put a load on that battery it will fail. Everyone should own a hydrometer.

:C

[Gundog]

After the batteries went to 9 volts and I ran the generator for 3 hours they read 12.6 volts. I don't think they are gone but they are definitely not great. I have been charging them for 2 days now after adding the water so I will just have to see. I haven't had time to mess with it again. If the batteries are junk come spring I will replace them.

[MRUSA]

I agree. A gallon of water, dry plates, 9 volts, all points to betteries that are beyond saving. I think a new set of batteries are in your future and the improvement will amaze you.

[steved28]

Lot's of good suggestions and advice on this thread, but really, exposed plates trump everything said. Those batteries may well be junk now, 9 volts! I hope they come back for you, but personally I would be shopping.

[oldave]

Two things hard to get used to

1 - How fast your batteries will run down ( 9 volts is way past dead )

2 - How long it will take to recharge them
hint , along time

[Big_Katuna]

Next you get figure out your lpg gauge. When it reads half full it’s 3/4 full. When it reads empty, it’s still 1/2.

Pro Fill info

Clicky

This doesn’t auto fill. You still have to plug in the squeeze bulb and fill monthly.
But it beats standing on your head with a mirror and a flashlight trying to peer into your battery while the threaded tie downs lacerate your face.

SHOP,SHOP,SHOP.
Some don’t include the bulb, some pictures show four batteries but only includes stuff for two.

Someone mentioned a brand that automatically fills but I have never found one.

If you don’t leave it plugged in all the time you probably don’t need one.

One last suggestion is to set the thermostat on 60 and bring more blankets.

[down_home]

double post

[down_home]

You may be able to install auto gen start in your controller. When batteries get to set level the generator will kick in automatically to bring them up.
For some reason I'm having trouble going to all the replies so this has probably been covered.
I am just about convinced your batteries are marginal, but may just be low electrolyte.
Yo get higher rate of charge by running the generator, and just a little from shorepower.
By this time you have checked the batteries and are replacing them I bet.